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Effects of treatment with low ozone concentrations on stomatal behavior, growth, and susceptibility to… Rosen, Peter Mark 1979

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EFFECTS OF TREATMENT WITH LOW OZONE CONCENTRATIONS ON STOMATAL BEHAVIOR, GROWTH, AND S U S C E P T I B I L I T Y TO ACUTE OZONE INJURY by P e t e r Mark Rosen B . A . , U n i v e r s i t y o f C h i c a g o , 1970 M . S c . , U t a h S t a t e U n i v e r s i t y , 1972 T h e s i s S u b m i t t e d In P a r t i a l Fulfillment Of The R e q u i r e m e n t s F o r The D e g r e e o f Doctor of Philosophy  in  the  Department of  Plant  Science in  THE PACQMT OF GRADUATE ST UDIES . We a c c e p t t h i s t h e s i s as c o n f o r m i n g to the r e q u i r e d s t a n d a r d  The U n i v e r s i t y  of  B r i t i s h Columbia  O^Wrr)., 197 9 ©  Petes' Mark Rosen, f 979  In presenting  this thesis in partial  fulfilment of the requirements fo  an advanced degree at the University of B r i t i s h Columbia, I agree that the Library shall make i t freely available for reference  and  study.  I further agree that permission for extensive copying of this thesis for scholarly purposes may by his representatives.  be granted by the Head of my  Department or  It is understood that copying or publication  of this thesis for financial gain shall not be allowed without my written permission.  ,. Department or n  ^  Plant Science _ _ _ _ _  The University of B r i t i s h Columbia 2075 Wesbrook P l a c e V a n c o u v e r , Canada V6T 1W5  O c t o b e r 31,  1979  i  Abstract Sub-acute visible  ozone e x p o s u r e s  injury)  behavior, sequent  have been f o u n d t o  and the  acute  (doses below  extent  exposures  of v i s i b l e (doses  The i n t e r r e l a t i o n s h i p s  according  to  and t h e  magnitude  particular  G o l d Wax)  were r a i s e d  treated with (six  0.02  hours per  parts  day), to  after  exposure)  maintained  acute  throughout  low ozone t r e a t m e n t  less  susceptible air.  the  acute  Treatment  were f o u n d t o At  to  early  treated plants  of  at  effects the  for  (ppm)  eight  than  air.  than  differences  visible  pretreatment  vulgaris air  L.  that  and t h e n  of  Seedlings  i n acute  differences  in  injury  controls exposed  maintained  stomatal  behavior.  ozone-p're-  r e s i s t a n c e when m e a s u r e d i n  filtered  air,  stage  decreased acute  had a r e d u c e d t e n d e n c y , t o  ozone e x p o s u r e  (0.4  susceptibility,  ppm).  in  susceptibility  air  an a c u t e  to  became  filtered  to  days  sowing,  in  response  p're-  six  s e v e n days  increased s u s c e p t i b i l i t y ,  stomata  dose  cv Pure  of v i s i b l e  controls  maintained  sub-  varied  days a f t e r  an a d d i t i o n a l  injury  for  ozone f o r  extent  greater  stomatal  tested.  filtered  (the  filtered  and c o n t r o l s  ozone-pretreated  of  was  c o r r e s p o n d to stage  same s t o m a t a l  injury  in  this  filtered  these of  for  i n r e s p o n s e to  (Phaseolus  per m i l l i o n  beginning  growth,  threshold  and t i m i n g  from s e e d i n  susceptibility an a c u t e  of  o f b u s h bean  plant  the  s p e c i e s and c u l t i v a r  When s e e d l i n g s  threshold  injury  above  injury).  the  affect  the  At  had but  close the  the  in  later  ozone-pretreated  ii  stomata  still  closure,  but  increase  in  exposures.  had t h i s  ozone p r e t r e a t m e n t  resistance in  Stomatal  entry  for  the  of  i n bean.  Exposure of mint  cuttings  ozone i n c r e a s e d t h e i r tolerance  acute  In Bailey)  for  (containing  three in  "naturally  l e a v e s , but  weight  filtered  air  This  growth  occurred also in  and f r e s h w e i g h t ) .  Within  'Delaware')  the  related  to  the  sensitivity  of  injury;  t h e most s e n s i t i v e i n c r e a s e i n ambient the  grapevine  significant  effect  of  susceptibility.  to  0.02 ppm  the  growth  (Vitis  air  dosage  labruscana,  an e n t i r e  three  air  growing  air  in  two  of  greatest  (both  dry  cultivars  ('Ives',  s t i m u l a t i o n was  directly  vines  'Ives',  to  ozone  showed t h e  as compared t o  case,  that  charcoal-filtered  filtered  c u l t i v a r s . showed any  that  than  ambient  and r o o t s  field-grown  cultivar,  The ozone  s t i m u l a t i o n was  c h r o n i c exposure to In  resulting  greater  i n ambient  trunks  part,  injury).  or  for  acute  in  ( b a s e d on t h e  grapevines  r e d u c e d ozone l e v e l s )  O n l y one o f  times  chambers e x p o s e d to  and  acute  six  o c u r r i n g " ozone)  tested.  to  susceptibility slightly.  'Concord',  growth  arvensis L.)  growth was f o u n d to be g r e a t e r  cultivars  prior  susceptibility  degrees of v i s i b l e  i n open-top f i e l d  season,  in  (Mentha  experiments with p o t t e d  (containing air  equivalent  air,  overall  ozone may t h u s p r o v i d e ,  o f m i n t was a p p r o x i m a t e l y  o f bean s e e d l i n g s r a i s e d i n required  filtered  differences  treatments  to o z o n e - i n d u c e d  a l s o r e s u l t e d i n an  stomatal  an e x p l a n a t i o n from these  reduced s e n s i t i v i t y  air.  statistically  ambient  'Delaware',  greatest  o z o n e on the  cultivar  iii  most r e s i s t a n t to  acute  to  injury  grapevines,  ozone i n j u r y  were  low ozone p r e t r e a t m e n t  in  the  closure  acute  in overall  vigor, air,  rather  regulating  ozone e n t r y  into  the  Although there  were  stomata p l a y  in  sub-acute  ozone d o s e s ,  there  of  of  the  ozone p r e t r e a t m e n t  'Delaware').  (0.75  air  than  to  to  In  an  stomatal  a s t o m a t a l mechanism  leaf. between  species in  was  the  suggestion of  toward  a protective  a  ('Ives'  and  'Concord'  the with  general effect  i n more o z o n e - s e n s i t i v e s p e c i e s  or c u l t i v a ' r s  and  ppm).  response to pretreatment  increased tendencies  versus mint)  filtered  decrease  those w i t h beans, decreased  differences  that  trends  tended to  a s s o c i a t e d with a lower  filtered  With  effects  but  a p p e a r e d t o be more c l o s e l y r e l a t e d  in  pattern  behavior,  ozone e x p o s u r e s  resistance  role  significant  ozone p r e t r e a t m e n t  with grapevines, unlike  susceptibility  was p r e d i s p o s e d  w i t h low o z o n e .  r e s i s t a n c e when m e a s u r e d i n  i n response to  increase  on s t o m a t a l  indicated that  experiments  field,  no s t a t i s t i c a l l y  of  both stomatal  the  by c h r o n i c p r e t r e a t m e n t  there  data  in  versus  (bean  iv  TABLE OF CONTENTS Abstract.  •  •  •  •  •  •  •  »  .  .  ,  .  ,  .  )  .  ,  .  .  i  Introduction  1  Review  5  of  Literature  Dose-Inj ury-Background  5  Pretreatment-Susceptibility  10  Stomata  .16  Growth Materials  31  and Methods  36  Bean and M i n t  .36  Grapevines  39  Results..  44  Susceptibility  44  Stomata  58  Growth  67  Discuss ion  .  Summary. Literature  -  80 -  Cited  98 .102  V  L I S T OF TABLES  1.  2. 3.  4. 5. 6. 7. 8. 9. 10.  11.  Ozone m o n i t o r i n g d a t a , A u g u s t 1 t o S e p t . 1977, f o r o p e n - t o p chamber e x p e r i m e n t  9, 42  Acute i n j u r y s u s c e p t i b i l i t y of greenhouse r a i s e d bean and m i n t a f t e r s u b - a c u t e p r e t r e a t m e n t Acute i n j u r y s u s c e p t i b i l i t y g r a p e v i n e s grown i n a m b i e n t filtered air.  .  .45  of potted a i r or c h a r c o a l 52  S t o m a t a l b e h a v i o r o f p o t t e d g r a p e v i n e s grown i n ambient a i r or c h a r c o a l - f i l t e r e d a i r Growth o f p o t t e d ' I v e s ' v i n e s a i r or c h a r c o a l - f i l t e r e d a i r .  i n ambient . . . . . .  .  .66 71  Growth o f p o t t e d • ' C o n c o r d ' V v i n e s i n ambient a i r or c h a r c o a l - f i l t e r e d a i r  72  Growth o f p o t t e d ' D e l a w a r e ' v i n e s i n ambient a i r o r c h a r c o a l - f i l t e r e d a i r  73  'Delaware': simple c o r r e l a t i o n s of growth, i n j u r y , ' and s t o m a t a l b e h a v i o r , September  75  'Ives': injury,  76  simple c o r r e l a t i o n s of growth, and s t o m a t a l b e h a v i o r , September  'Concord': simple c o r r e l a t i o n s of growth, i n j u r y , and s t o m a t a l b e h a v i o r , September  78  Summary o f i n d i c a t i o n s c o r r e l a t i o n s o f growth in grapevines,  79  from v i n e - t o - v i n e and ozone s u s c e p t i b i l i t y  vi  . LIST OF"FIGURES 1.  Mint bed i n greenhouse. . .  2.  Acute ozone i n j u r y to bean. .  3.  Acute fumigation chamber f o r t r a n s p i r a t i o n measurement  37  4.  Open-top chamber i n v i n e y a r d .  40  5.  Acute ozone fumigation chamber, experiments  6.  Acute ozone i n j u r y to bean p l a n t s with v a r i o u s sub-acute doses  7. 8.  9.  37 : . .37  grapevine  40  pretreated 47  E f f e c t of i n c r e a s i n g pretreatment dose on acute ozone s u s c e p t i b i l i t y of beans  . 49  Acute ozone s u s c e p t i b i l i t y of beans a f t e r growth i n continuous f i l t e r e d a i r or v a r i o u s p a t t e r n s of d a i l y exposure to 0.0 2 ppm ozone Stomatal conductance of beans during sub-acute pretreatment and subsequent acute treatment with ozone  10. T r a n s p i r a t i o n rates of attached primary bean leaves during acute ozone exposure, a f t e r pretreatment w i t h e i t h e r f i l t e r e d a i r or 0.02 ozone  55  . .60}  ppm  .62  11. Height of bean p l a n t s grown i n f i l t e r e d a i r or 0.02 ppm  ozone  12. Model of ozone pretreatment mechanism. 13. Growth of p o t t e d 'Ives' vines i n ambient a i r or c h a r c o a l - f i l t e r e d a i r 14. Growth o f p o t t e d 'Concord' vines i n ambient a i r or c h a r c o a l - f i l t e r e d a i r  68 .84 93 94  vii  Acknowledgements  I would l i k e for  his patient  e x p r e s s my t h a n k s  and p e r c e p t i v e study,  of  expert  a d v i c e on numerous q u e s t i o n s o f  and t o D r .  entire  staff  New Y o r k S t a t e their  V.  C. Runeckles, the  Peter A. J o l l i f f e ,  for  experimental  his  method and  presentation.  I am e s p e c i a l l y g r a t e f u l the  to D r .  s u p e r v i s i o n through  course  written  this  to  of  the  to D r .  Department  Agricultural  Walter  J . Kender,  o f Pomology and  Experiment  Station,  and  Viticulture,  Geneva,  for  s u p p o r t and i n s p i r a t i o n . I would a l s o l i k e  and f r i e n d s ,  for  their  to  e x p r e s s my a p p r e c i a t i o n t o  quiet  faith.  family  viii  List  ABA  -  abscisic  h  -  hours  kPa  -  10  K  -  stomatal  of A b b r e v i a t i o n s  acid  3  s  pascals,  1 p a s c a l = 1 newton p e r  conductance; inverse of  square  stomatal  meter  resistance  (see R ) LAN  -  percent  min  -  minutes  NAR  -  net  leaf  area  assimilation rate,  unit  leaf  change i n p l a n t  dry weight  per  area  PAN  -  PAR  -  photsynthetically  ppm  -  parts  RH  -  relative  R-^  -  leaf  R  -  stomatal  SE  -  standard error  sec  -  seconds  wt  -  weight  ^E  -  10"  g  necrotic  peroxyacetylnitrate  6  per m i l l i o n ,  active  radiation,  by v o l u m e , m i c r o l i t e r s  per  liter  times  the  humidity  r e s i s t a n c e to w a t e r v a p o r  flux  r e s i s t a n c e to water vapor of  the  1 quantum o f  flux  mean  E i n s t e i n s ; 1 E i n s t e i n = 6.02  energy of  -  light  of  x 10  2 3  a given  wavelength  1  Introduction  The p o s s i b i l i t y o f  a deleterious  agricultural  p r o d u c t i o n was f i r s t  the b a s i s of  visible  on g r a p e  (Richards  Middleton,  symptoms o f  et  1959) .  al.,  A great  been c o n c e r n e d w i t h t h e of  injury,  l e a d to other  the  aspects of  scientists the  in  arising  fleck)  o f work s i n c e t h a t  on  observed  t i m e has  specific characterization of  environmental of  of  this  factors  aid  practices  type  which  susceptibility,  s i t u a t i o n which might  to  this  and  agricultural to  alleviate  loss  of  active  into  c o n s i d e r e d the  effects  visible studies  (Heck  et  effects  p o s s i b i l i t y of production  from exposures r e s u l t i n g  investigations  injury.  the  in v i s i b l e  photosynthetic  effect of  of  e x p o s u r e to  While  this  al.,  1977)  i.e.,  area  By way o f  to  area,  and  more  doses b e l o w logically  the  recently, have  the  threshold  i n c l u d e s a number  been c a l l e d " s u b t l e  visible  chronic e f f e c t s ,  e x p o s u r e to  injury,  effects,"  p h y s i o l o g i c a l and b i o c h e m i c a l  w h i c h may o c c u r p r i o r  long-term  losses  ozone on a g r i c u l t u r e  i n t o what have r e c e n t l y  f o c u s has b e e n t h e of  deal  recommending c u l t u r a l  addition  consequent  of  (leaf  1950's,  and t o b a c c o . ( H e g g e s t a d and  or l e s s e r degree the  the  ozone on  problem. In  for  noted i n injury  1958)  investigation  a greater  effect' of  injury,  its  major  particularly  the  effect  s u b - a c u t e doses  definition,  "acute" here  on p l a n t refers  to  growth. an ozone  2  exposure visible  that injury  of n e c r o t i c this  this  effects, injury acute  in  ozone e x p o s u r e  ozone,  the  total  is  effect  in  our  the  of  the  of  possibility  the  improve  to  1975).  of  extent  to  accompanied  of  it  (e.g.  effective effect,  background l e v e l s  interaction  of  two  to  of  types  explain  two  of  ozone  injury  from the Macdowall,  sub-acute pretreatment a more  these  an a c u t e  greater  or p r o t e c t  second exposure to  of  Because  t o be  ability  Work  sub-acute  exposure.  our  a  premature  on the  between  shown t h a t  The mechanism most o f t e n protective  below  another  aspect  likely  exposure  from a subinjurious 1965).  exposures  form of  framework,  Shifting  raises  acclimation,  and i n t r o d u c e s  a c c l i m a t i o n w i t h i n an e v o l u t i o n a r y natural  form  exposures.  have  on a p o s s i b l e p r o t e c t i v e of  is  interaction  field  exposure  the  interest  in  Weinstein,  acute  some  specifically  exposure  field  predispose a plant  acute of  sub-acute subsequent  P r e v i o u s workers  sequent  (see  of  any e x p o s u r e  chlorosis,  one p a r t i c u l a r  n e c e s s a r y to  effect  may e i t h e r  symptoms  e x p o s u r e and an i n c r e a s e d b a c k g r o u n d l e v e l  knowledge  exposure  to  results  usually  reduction  of  response to  by s u b - a c u t e  that  injury,  involves  effect  refers  "chronic" refers  exposure  and growth  the  characteristic  "Sub-acute"  form o f  thesis  the  species considered, usually  whereas  sub-acute  senescence,  in  the  fleck.  recognizable  of  in  threshold,  long-term  in  results  the  the  based question  b a s e d on  ozone.  c o n s i d e r e d as a b a s i s  for  acute  involves  ozone e x p o s u r e s  the  3  the  effect  Although  of  the  demonstrated  the  prior  existence  exposure of  experimentally,  known t e n d e n c y  of  1965),  importance  to  the  occurs in  and the  ozone  ozone i n s o f a r . a s  into  leaf  et  i n r e s p o n s e to  to  duration in  it  al. acute  growth. battery  reductions  use o f  charcoal-filtered  in  either  a single  further  to  of  the  provide  emissions of objective  of  information  susceptibility toxic  gas  c l o s u r e s u c h as  thereby  the  dioxide effect  assess  on  ozone  exposure  and  chronic exposure, with  the  the  acute  the  associated  and c a r b o n  used to  occur  reducing  in  a significant  as a c o n t r o l  treatment,  situation.  the  field  seriously  The  to background l e v e l s  episode i n  of  or over  ozone the  s p e c i e s must be c o n s i d e r e d i n  our u n d e r s t a n d i n g  The f i r s t  have  of  (Macdowall,  exposures, but,  r e s p o n s e to  air  acclimation  history  anthropogenic  was  in  the  s  the  d o s e s may a l s o  doses,  techniques  complexity  of  to  to  r e s p o n s e to  possibilities  evolutionary  of  injury  growth  during  Stomatal  of water vapor  plant  the  of  sub-acute pretreatment,  exchange  visible  acute  from  closure  entry  pretreatment  c o u l d a l s o be e x p e c t e d  The c u r r e n t  naturally  (R- ) •  been  in "regulating  the  , 1970).  subsequent  of  the  underestimates  stomata  control  (CC^)  tolerance,  follows  induce stomatal of  resistance  mechanism has n e v e r  sub-acute pretreatment  susceptibility  reduction  to  they  (Rich  r e s p o n s e to  longer  this  on s t o m a t a l  of plant  response to  order  current  ozone p r e c u r s o r s . t h e work d e s c r i b e d i n about  the  effect  of  this  thesis  pretreatment  4  with sub-acute injury,  ozone doses  and p a r t i c u l a r l y  acclimation  to  ozone.  exposure w i l l  responses  to  is  agricultural for  affect  the  field,  prediction  relationships the  vitally  of  for  areas  occurrence of  that  of  exposures,  our  ability  ozone s t r e s s . or  in  any  of  acclimation  cultural  the  and p a r t i c u l a r l y  to  of  stomatal  this  In  examine  the  acclimation.  The i m m e d i a t e  stomatal  possibility  situations  closure this  to p l a n t  depends  growth.  s t u d y was  stomatal  season.  yield  drastically  to  in  of  e x c l u s i o n mechanisms,  protective  could  for  s t u d y was  role  any p o s s i b l e  of  adapt  agricultural  designed  to  to  of the  injury  dose,  ozone  some e x t e n t  and the  the  growth  in  acclimation on t h e  relation  Consequently,  plant  acute  responses,  effective  investigate  c l o s u r e to  and  the  avoidance mechanisms,  exploiting to  investigate  sub-acute  observed v i s i b l e  ozone and r e d u c t i o n  agricultural  to  breeding  practices  r e s p o n s e to  e x c l u s i o n of  in  in  stress.  ozone e x p o s u r e w i t h the  growing  improve  of  example,  plant  ozone a c c l i m a t i o n  n e c e s s a r y to to  and the  b a s e d on c o n t r o l l e d  possibility  efficiency  of  sub-acute  the  practices  relationship  of  between  ozone o b s e r v e d i n  The s e c o n d o b j e c t i v e  objective  interaction  of  of  the  counterract  stomatal  possibility  where ozone e x p o s u r e may be r e s p o n s i b l e  reductions,  ozone  interpretation  ozone t o l e r a n c e ,  situation  any  the  acute  the  about  particular  investigate  to  affect  dose-injury  knowledge  to  While  and a c u t e  of  on s u s c e p t i b i l i t y  of  the  role  protective third  relationship over  an  entire  5  Review  of  Literature  Dose-Injury-Background An e n v i r o n m e n t  where ozone  elevated  due to  receives  a combination  mean,  pollutants,  exposure  used to  of  With s u l f u r  estimate  be u s e f u l l y  the  applied  equations,  to  to  dioxide  s u c h as  which  technique  is  exposures  are  not  are  design of  assumptions  about  to  ozone.  on the  poorly  c o n v e r s i o n , and a r e  on the  of  1976;  derived  emitted d i r e c t l y  empirical  Eschenroeder,  1977;  lognormal  Revlett,  and c a n  experiments the  from  frequencies  these  the  experimenter  the  exposure  produced i n  Models  of  could  pattern. the  primary  by p o i n t  pollutants  sources, Larsen's field  ozone  understood processes  most o f t e n  monitoring  c a n be  1971)  By t a k i n g  from p r e c u r s o r s , u n l i k e  of precursor basis  by  long-term  concentrations  dependent  point  distribution  (Larsen,  exposures.  applicable  increased  (SC^) , s u c h e q u a t i o n s  a secondary p o l l u t a n t ,  indirectly  ozone p r e c u r s o r s  Given a  c a n be e s t i m a t e d  and c o m b i n i n g them r a n d o m l y ,  B e c a u s e ozone i s  of  known e m i s s i o n s , t h e  the  various  consistently  concentrations.  field  a v o i d any u n w a r r a n t e d  atmosphere  production  exposure f u n c t i o n  which would s i m u l a t e exposure  are  increased background,  concentrations  equations.  of  of  and o c c a s i o n a l peak  source of of  anthropogenic  levels  data  1978).  constructed  (Johnson et A  general  solely  al.,  6  mathematical therefore  d e s c r i p t i o n of  the  exposure f u n c t i o n  not p o s s i b l e w i t h ozone,  and t h e b e s t  be done a l o n g s u c h l i n e s w o u l d n e c e s s a r i l y be  is  that  could  locality  specific. .In  experiments  derived  from the  with S 0 ,  exposure  ?  to  t h e mean v a l u e s  c o m b i n a t i o n o f peaks p r e d i c t e d by L a r s e n ' s  t e c h n i q u e was shown n o t  to  result  in  injury  equivalent  that  c a u s e d by e x p o s u r e to  randomized combinations  with  the  (Male,  This  non-linearity  same o v e r a l l  ozone a l s o ,  between  though  same manner.  it  presentation  acute  to  higher  time a r e the  in  less  Qualitative concentrations  speculation exposures  four  0.6  parts  per m i l l i o n  (ppm),  D u n n i n g , and H i n d a w i  (1966)  of  injury  three-dimensional  is  hours  or  equivalent  shorter in  to  this  longer  a variety  is  as y e t  area.  In  duration,  lower  and initiated."  of  the  concentrations  injury  response at  within a short-term  no t h e o r e t i c a l context  however,  at  of  as  time.  of p h y s i o l o g i c a l  the  of  doses p r e s e n t e d  periods  the  exposure t i m e s ,  there in  for  (h),  response surface  e x p o s u r e s at  than  differences  may be a t t r i b u t e d but  the  up t o  required before  injury  concentrations  effects,  in  of  threshold concentration  longer  peaks  has b e e n shown w i t h  x c o n c e n t r a t i o n x t i m e was c o m p l e x , b u t  t r e n d was f o r  result  ozone up t o  of  communication).  has n e v e r b e e n d e m o n s t r a t e d  a "definite  species,  injury  general  of  personal  d o s e and i n j u r y  b e a n and t o b a c c o , H e c k ,  showed t h a t  For both  L.,  U s i n g exposure times  and c o n c e n t r a t i o n s with pinto  mean  to  different range,  threshold  framework  for  field-type  least  one  major  7  qualitative between  d i s t i n c t i o n has b e e n r e c o g n i z e d ,  acute  distinction  and c h r o n i c r e s p o n s e s .  The A m e r i c a n P h y t o p a t h o l o g i c a l Weinstein,  the  1975)  defines  two  types  Society of  air  glossary  pollution  (see injury  as f o l l o w s :  •  "Acute i n j u r y - - injury u s u a l l y i n v o l v i n g n e c r o s i s w h i c h d e v e l o p s w i t h i n s e v e r a l h o u r s t o a few days a f t e r s h o r t t e r m e x p o s u r e t o a p o l l u t a n t , and e x p r e s s e d as f l e c k , s c o r c h , or b i f a c i a l n e c r o s i s . Chronic i n j u r y - - i n j u r y which develops only a f t e r l o n g t e r m or r e p e a t e d e x p o s u r e t o an a i r p o l l u t a n t , and e x p r e s s e d as c h l o r o s i s , b r o n z i n g , p r e m a t u r e s e n e s c e n c e , r e d u c e d growth r a t e ; can i n c l u d e n e c r o s i s . " By c i r c u l a r loosely  definition,  identified  these  with  two  two  types  and c h r o n i c e x p o s u r e ; whereby dose)  is  one w h i c h  exposure This  (or  visible  identification  s u c h as the  injurious  of  is  injury  exposure,  an a c u t e  acute  of  injury  one w h i c h  (or  exposure acute  and a c h r o n i c leads  masks a number o f  d e s c r i p t i o n of  c a n be  acute  exposure  to  chronic  injury.  ambiguities,  exposures which  p h y s i o l o g i c a l changes which are  not  lead  manifest  to  as  symptoms.  The terms  "hidden injury"  introduced early  in  for  this  a history  controversy to  to  c h r o n i c dose)  simple  however,  leads  types  of  about  the  19th  century  usage),  their  or " i n v i s i b l e  usage  .  McCune et  al.  be d i s c a r d e d as a r e d u n d a n t  (see McCune e t  but  there  is  (as  it  inherently  " c o n s e r v a t i o n i s t s " and i n h e r e n t l y  trialists")  injury"  (1967)  is  a great  unappealing  suggested that  formulation  for  were al.,  deal  1967 of  appealing  to  "indus-  the  chronic  terms injury.  8  Heck e t  al.  (1977) have p r o p o s e d the  term " s u b t l e  d e s c r i b e b i o c h e m i c a l and p h y s i o l o g i c a l changes pollutant  exposure  that  are  The c o n s i d e r a t i o n , o f of  pollutants  introduces  into  the  the  a portion  tentatively  i n r e s p o n s e to  injury,  although  chlorotic  as compared t o  contended that the  field  this  concentrations solution.  make  probable  plants  of  the  this  areas,  ozone o r  (e.g.  still  Stasiuk  further.  accumulations occurred prior  of to  Bell  to  ryegrass  and  portion (1973), in  rye-  invisible  slightly  filtered  air.  They  evident  grown o u t d o o r s  in  in  same symptoms. data  relatively  removed from t h e  and C o f f e y , Chambers  has  (1976). a r g u e s  direct  urban  long  distance  appear  complicated that  atmosphere would not  the w i d e s p r e a d  ozone  typical  does n o t  1974),  atmospheric  high  i n c a s e s where the  ozone p r e c u r s o r s  the  on  i n a c c e s s i b l e to  discovery of  ozone i n  were  normal  levels  reduction  S C ^ , as  plants  grown i n  problem  far  the  and C l o u g h  c h l o r o s i s w o u l d n o t be  ozone p r e c u r s o r s , of  c a u s e s and a  absence of h i s t o r i c a l  The r e c e n t  in rural  transport  issue  the  the  levels  are. exposed,  a yield  exposure  b e c a u s e any c r o p o f  For ozone,  sources  designated  slight  England would'manifest  levels  sources.  conceding that  low  these background  from'natural  chronic  to  symptoms.  determining  to w h i c h p l a n t s  from a n t h r o p o g e n i c  example,  grass,  resulting  exposures  to  i n d u c e d by  as v i s i b l e  question of  problem o f p a r t i t i o n i n g  resulting for  manifest  long-term  background c o n c e n t r a t i o n s raises  not  effects"  use o f p e t r o l e u m  the  significant have fuels  in  9  the  20th c e n t u r y .  calculated c o u l d not  that  Stasiuk  current  and C o f f e y  high  be a c c o u n t e d f o r  ozone  and s u g g e s t e d t h a t  stratosphere  down t o  extension,  this  of  history  of  of  possibility,  current  Ludwig e t  Weinstock, workers be  the  species.  and o f  the  in  the  down f r o m the  urban  and t h e  recent  these  of  ozone  questions  1977;  local of  high  study  transport  Chang and  1978).  rural  including,  destruction  By  evolutionary  that high  stratosphere,  cause.  accounted f o r  and A l t s h u l l e r ,  causes,  from  the  be t h e  range  al.,  areas  in  These  levels  may  addition  sources,  to  long  ozone by n i t r i c  oxide  environment.  Bennett  et  al.,  ozone may a c c o u n t ozone i n p l a n t s , observed in  et  possibility  of m u l t i p l e  transport,  the  from  the  clarified  Coffey  Dimitriades  consider  transport range  1977;  1977;  rural  Intensive  long  however,  precursors  might  ozone t h r o u g h o u t  plant  al.,  result  of  transport  troposphere  and ozone p r e c u r s o r s , has n o t (see  in  same mechanisms) c o u l d have  background l e v e l s  this  levels  by t r a n s p o r t  urban a r e a s ,  the  (1974),  for  (1974)  argue  that natural  sources  significant  evolutionary  adaptation  on the  r e s p o n s e to  The i n t e r p r e t a t i o n  of  to  into  ozone must  take  air  treatments  the  interaction  do n o t  low  of  plant  ozone  experiments account  represent  between  a l s o be d e t e r m i n e d  basis  levels  valid  controls.  how p r e t r e a t m e n t w i t h  filtered  chronic  possibility  and a c u t e  to  stimulations  added t o  involving  this  sub-acute  growth  of  exposure  that In  filtered  studying  exposures,  filtered  air.  air  it  must  prior  10  to  acute  e x p o s u r e compares  of  ozone.  to pretreatment w i t h  low  levels  Pretreatment-Susceptibility The a l t e r a t i o n  of plant  ozone e x p o s u r e  can manifest  susceptibility susceptibility  either  as an i n c r e a s e  in  to^injury  (predisposition)  or a reduction  in  to i n j u r y  (protection).  one form o f i n j u r y to  suppose t h a t  visible  injury  exposure will  a r e above  appear  and i t  nonetheless  that  injure  injury  threshold.  from This  are l e s s  straightforward,  stresses  as a r e s u l t  heat,  chloride, manganese,  drought,  phenomena,  zinc,  that,  the t h r e s h o l d the p l a n t  other  chromium, b o r a t e ) ,  only  for  exposures  phenomenon w i l l  then  t h e two  by p r i o r  b u t s u c h phenomena a r e variety Levitt  ultraviolet  toxic  is  i n some  subsequent  ions  of other (1972) light,  (copper,  plant  mentions sodium  selenium,  and h i g h p r e s s u r e ,  in  P r e v i o u s work w i t h ozone p r e t r e a t m e n t s  has  under  these  differing  conditions,  p r e d i s p o s i t i o n or p r o t e c t i o n ,  Macdowall factors  low l i g h t ,  heavy m e t a l s ,  category.  indicated  of a c c l i m a t i o n .  injury  unreasonable  o r s y n e r g i s m between  known t o o c c u r i n r e s p o n s e t o a w i d e  this  i s not  P o s s i b l e mechanisms o f p r o t e c t i o n  exposures  cold,  Visible  t o doses below  as p r e d i s p o s i t i o n ,  doses.  itself  expression,  way w h i c h may c o m b i n e . w i t h which  r e s p o n s e t o ozone by p r e v i o u s  (1965)  of  may o c c u r .  i n c l u d e d ozone i t s e l f  he s t u d i e d w i t h r e s p e c t  either  among t h e  chemical  to the p r e d i s p o s i t i o n o f  11  tobacco  to  ozone i n j u r y ,  of p o l l u t i n g  and c o n c l u d e d t h a t  ozone o f t e n  appeared to  act  a s e c o n d c o n s e c u t i v e low d o s e , " whereas acted a n t a g o n i s t i c a l l y followed." in field of  against  days.  after  of  a constant  exposure per  day,  the  of  about  concentration 0.54  ppm-h works  ppm.  Macdowall  terminology,  dose o f  0.04  to  b a s e d on the opening.  solvent  The o n l y was  the  tobacco  0.26  plants  in  unfiltered greater  filtered  air  an  average  of  approximately  for  of  (to  0.08  stomatal  the  antagonism)  determining  stomatal  this conclusion,  c l o s e d stomata  on some newly  the  ozone,  range  of  in 0.03  symptom  an a r e a where to  while  0.10  same phenomenon o f  c o n s e c u t i v e low d o s e s . air  development  exposing others  ppm,  They h e l d some continuously  which had been c o n t i n u o u s l y exposed  than  on p l a n t s  Heagle  synergistic  and f o u n d t h a t new symptom d e v e l o p m e n t  on p l a n t s  unfiltered  ambient  observed the  between  air,  of  " h i g h " dose  factor"  system of watching  l e v e l s were i n  interaction  on  leaves.  on t o b a c c o e x p o s e d to  (1974)  the  "inhibition  evidence presented  observation of  indices  ppm-h y i e l d s  i n f i l t r a t i o n method o f  Using a s i m i l a r  and Heck  immediately  during seven h  ppm, w h i l e  say t h a t  pollutant  e p i s o d e s on a s e r i e s  a s e v e n h mean o f  goes on t o  with  roughly c a l c u l a t e d  concentration  "low"  out  ambient  o p e n i n g may have b e e n a c o n t r i b u t i n g  ambient  " h i g h doses o f  h i g h doses t h a t  exposure to  By M a c d o w a l l ' s  the b a s i s  flecked  synergistically  T h e s e c o n c l u s i o n s were b a s e d on f l e c k  plots  however,  " a low dose  w h i c h were s w i t c h e d f r o m  to  was to filtered  12  air  to  unfiltered  chronic was  injury  air.  This  suggested that  w h i c h was n o t  expressed in v i s i b l e  a p r e d i s p o s i t i o n , a case of hidden or  w h i c h c o m b i n e d w i t h and a m p l i f i e d to  later  phenomenon o f  plants  (1967),  in  from i n j u r y  30 m i n u t e  by o n e ,  two,  i n r e s p o n s e to  (min)  or  fumigation. between  three  the  various  than  injury  f r o m two  possibility  partial  with  of  injury  h i g h d o s e s may  they  effect  of  the  to  four  ppm,  i.e.,  ozone,  h,  total  of  daily  For treatments  different  two  patterns,  exposures per  concentrations  They c o n t i n u e d t h i s day.  the  greater to  the  first  interval  to  results.  doses o f  half  exposures,  possibility  interfumigation  Heck and D u n n i n g a l s o e x p o s e d t o b a c c o to daily  min  differences  addition  Heck and D u n n i n g a l s o s u g g e s t e d the  these  60  t i m e between  In  from  separated  a single  c l o s u r e i n r e s p o n s e to  recovery during  doses.  f r o m a 60 min e x p o s u r e was  30 min e x p o s u r e s .  stomatal  protect  ppm ozone  any s i g n i f i c a n t  o£ r e c o v e r y  found  compared i n j u r y  w i t h 0.30  the  find  lengths  cases,  exposure,  h,  They d i d n o t  in a l l  explain  i n response  experiments,  subsequent h i g h  bean,  fumigations  but,  of  injury  symptoms  laboratory  a n t a g o n i s m , whereby  W o r k i n g w i t h t o b a c c o and p i n t o two,  symptoms  invisible  visible  of  exposures.  Heck and D u n n i n g the  one a s p e c t  for  ranging  doses r a n g i n g five  days,  two  ranging  f r o m 0.02  f r o m 0.0 5 to  f r o m one to  0.20  and a s s a y e d i n j u r y  with equivalent e.g.,  day,  intermittent  daily  exposures per  doses, day o f  0.10 ppm-h. each  in one h a l f  h  13  each to to  0.10  ppm v e r s u s one e x p o s u r e p e r  0.0 5 ppm, t h e y  found that  concentrations  l e d to  may l i e  in  either  synergistic  by H e c k ,  and i n t o  tive  the  t h e b a l a n c e between  antagonistic  penetration  of  Due t o  i.e.,  the  Wilton bluegrass by p r i o r four h,  et  duration  (19 7 2 ) ,  ones.  centimeters and r e p e a t e d in  the  response to  been i n r e s p o n s e to way t o w a r d  ruling  c a s e be a t  least  extent  the  the  out  stomatal  a particular None o f  in  effec-  cultivars  a length  They f o u n d t h a t  first.  differences  internal  20 cm i n  the  exposures two of  or  2.5  greenhouse,  there  than  of  was  there  less had  T h i s p r o t o c o l goes a l o n g mechanisms  Their  the p r o t e c t i o n  (which w o u l d in- t h i s  results  also  indicated  r e n d e r e d by t h e  e x p o s u r e was c o r r e l a t e d p o s i t i v e l y w i t h of  to  second fumigation  indirect). of  to  of  stomata  ppm ozone f o r  clipped the.grass  fumigation.  length  from subsequent acute  allowed regrowth  it  1974).  They f u m i g a t e d w i t h 0.30  (cm),  this  noted  differences  a particular  for  or  t i s s u e s , these  working with various  a l s o found p r o t e c t i o n  assayed i n j u r y ,  the  of  ozone^see R u n e c k l e s ,  al.  the  ozone t h r o u g h t h e  palisade  -  higher  and  threshold function  (1966).  injury sensitive  concentration-of  that  the  to  The e x p l a n a t i o n  d e p e n d i n g on c o n c e n t r a t i o n ,  expression of  for  one h  exposures to  e x p o s u r e d u r a t i o n may a l s o r e f l e c t  dose,  injury  shorter  injury.  D u n n i n g , and H i n d a w i  time r e q u i r e d  due t o  greater  combination,  may be a n o t h e r  the  day o f  the  ozone  first sensitivity  cultivar.  these previous experiments  on t h e  effect  of  ozone  14  pretreatment effect of  on a c u t e  ozone s u s c e p t i b i l i t y  of a sub-acute pretreatment  sub-acute  studied, effect  exposure w i t h subsequent  however,  with SC^.  of sub-acute  Zahn  e x p o s u r e was e q u i v a l e n t  unpretreated  showed a p r o t e c t i v e  effect  but  w i t h data  genase,  aspartate  cose- 6-phosphate  levels  Wellburn gation  (Rumex  oxaloacetate  obtusifolius),  SC^ and from an a r e a response  to acute  carboxylase  this  enzyme,  effect.  the e f f e c t  glu-  a l l of which with  Horsman and SC^ f u m i -  carboxylase,  and p e r o x i d a s e ,  o f low b a c k g r o u n d S C ^ .  of high  i n dock background  They f o u n d t h a t  with SC^, ribulose  no e f f e c t  from h i g h background  in  diphosphate  was d e c r e a s e d and p e r o x i d a s e  a c t i v i t y was  while  t h e r e was  areas.  of P i e r r e ,  in  dehydro-  o f acute  diphosphate  from an a r e a  i n the experiments  also  symptoms  Pretreatment  from low b a c k g r o u n d a r e a s ,  Generally,  (1977)  injury  increased i n plants in plants  plants  phosphofructokinase,  transaminase, collected  after  SC>2 p r e t r e a t m e n t ,  ^treatment.  of ribulose  fumigation  activity  pretreated Pierre  and m a l i c  investigated  on t h e a c t i v i t y  glutamate  SO^  content,  content  Ke a s s a y e d f o r g l u t a m a t e  dehydrogenase,  also  of sulfur  The s u l f u r  of sub-acute  o f S O ^ , he f o u n d , n e g a t e d  (1977)  protective  i n wheat and l a r c h ,  plants.  aminotransferase,  were d e c r e a s e d by a c u t e low  e x p o s u r e has b e e n  b a s e d n o t on v i s i b l e  on enzyme a c t i v i t i e s .  interaction  showed a  in tolerant,  and i n s u s c e p t i b l e ,  Pelargonium,  acute  o f measurements  the mechanism was n o t s t o m a t a l .  acute  The  (1963)  SC^ p r e t r e a t m e n t  and s u g g e s t e d , on t h e b a s i s that  dose.  examined t h e  and t h o s e  of  15  Horsman and W e l l b u r n , levels  o f acute extent.  response  to acute  affected  r a t h e r than  exposure  given i n this on  of Pierre,  Although  t h e r e was  the e f f e c t  insignificant, from  acute  t h e a b s e n c e o f any growth  said  aspects  of. low l e v e l  exposure  background  was a s s o c i a t e d w i t h  or with  i n concert.  a growth levels  stimulation, c o u l d be  I f a protective  was a s s o c i a t e d w i t h  i n a polluted  exposure  t h e r e f o r e , that the  exposures  effect,  i n opposition with  no.evidence  or a s l i g h t r e d u c t i o n .  g r o w t h , however, t h e two p r o c e s s e s  productivity  and t h o s e o f  o f low l e v e l  o f a c c l i m a t i o n t o low p o l l u t a n t  t o have b e e n a c t i n g  working  U n l i k e the type o f  and c h r o n i c , t h e e f f e c t  g r o w t h , t h e r e was some i m p l i c a t i o n ,  two  o f enzymes  r e p r e s e n t e d more o f a c o n t i n u u m b e t w e e n  work about  If protection  on t h e  confined to levels of  of the e f f e c t .  levels.  e f f e c t was e i t h e r  occurred to a  to the spectrum  i n the experiments  Horsman and W e l l b u r n ,  from the  pretreatment  ?  d i s t i n c t i o n between a c u t e  o f SC>2 e x p o s u r e  they  f u m i g a t i o n were a l s o  or the d i r e c t i o n  qualitative  of S0  w i t h low  different  fumigation, although The e f f e c t s  enzyme'activity  various  o f treatment  o f SC>2 were n o t q u a l i t a t i v e l y  effects lesser  the e f f e c t s  a reduction i n  m i g h t be s a i d  r e s p e c t t o optimum environment.  effect  t o have b e e n  plant  I n an a r e a where low  l e v e l s were n o t c o n t i n u o u s , however, and where  the o c c u r r e n c e with  subsequent  that  induced  o f low b a c k g r o u n d acute  l e v e l s was c l o s e l y a s s o c i a t e d  e p i s o d e s , t h e e x i s t e n c e o f a mechanism  a protective  effect  even a t t h e expense o f some  16  growth  r e d u c t i o n might  Protective one example  still  effects  b a s e d on s t o m a t a l  closure  are  i n w h i c h p r o t e c t i o n m i g h t be e x p e c t e d t o  a s s o c i a t e d w i t h a growth between  be a d v a n t a g e o u s .  reduction.  s u b - a c u t e and a c u t e  understand t h e i r combination,  effects,  exposures, i t  both  on s t o m a t a l  To c l a r i f y is  the  be interaction  n e c e s s a r y to  independently  and  in  behavior.  Stomata Study o f falls  roughly  the  relationship  into  two  encompasses  a majority  of  aperture  stomatal  injury  to  the p l a n t .  relate  the  effect  between  areas. of  ozone and p l a n t  The f i r s t  t h e work  area,  done, c o n c e r n s the  this  work,  of v a r i a t i o n s  in  an a t t e m p t the  growth  prior  injury,  effect  exposure,  of  the  in  this  variations  a r e a have  responsible for  ozone s u s c e p t i b i l i t y o f in  aperture, not  of  i s made  the  the  (c)  that  complete e x p l a n a t i o n  conclusions  have  fallen  leaf  tissue,  independent  changes i n  plant  stomata  of  changes i n  into  category  of are  (a).that conditions  (b)  a partial  in  that  changes i n  susceptibility. (c),  the  aperture.  c o r r e s p o n d i n g changes  internal  s u s c e p t i b i l i t y are or  the  either  on s t o m a t a l  concluded either  of  to  by i n v o k i n g  changes i n d u c e d by c h a n g i n g e n v i r o n m e n t a l  are p r i m a r i l y  changes  extent  those environmental  Experimenters stomatal  to  of  effect  extent  environment,  d u r i n g ozone e x p o s u r e o r d u r i n g t h e to  which  d u r i n g ozone e x p o s u r e on t h e In  stomata  stomatal but Most  although o c c a s i o n a l l y  17  (a)  (e.g.,  Fletcher  T i n g 1974a) have  et  al.,  afforded  1972)  o r .(b)  a better  (e.g.,  explanation  Evans and of  experimental  results. The s e c o n d a r e a  of  s t u d y on t h e  ozone and s t o m a t a c o n c e r n s t h e stomatal  aperture  itself,  function.  Experimental  classified  as s h o w i n g t h a t  closure,  (b)  no e f f e c t  conditions, categories  protect  of  direct  results  in  either  this (a)  f r o m ozone (1973)  "The r o l e  of  stomata  pollutants,"  i n work  cell  can be  opening, or  (c)  stomatal ozone has  environmental  species,  each o f  these  T h e s e two on ozone  a r e a s may  pretreatment  c l o s u r e may a l s o  injury.  used a s i m i l a r  two-part  on ozone and p l a n t in determining where  area  on g u a r d  ozone i n d u c e s  because ozone-induced stomatal plants  between  ozone e x p o s u r e on  effects  Under d i f f e r i n g  particularly  c h a r a c t e r i z i n g work  air  of  r e s p o n s e has b e e n f o u n d .  Mansfield  to  i.e.,  and w i t h d i f f e r e n t  be i n t e r r e l a t e d , effects,  effect  ozone i n d u c e s s t o m a t a l  on s t o m a t a .  relationship  the  distinction  stomata,  in his  responses of  in  review,  plants  he b e g i n s ,  " S t u d i e s o f t h e p a r t p l a y e d by s t o m a t a i n d e t e r m i n i n g t h e s u s c e p t i b i l i t y o f p l a n t s t o a i r p o l l u t a n t s c a n be c o n v e n i e n t l y c o n s i d e r e d u n d e r two main h e a d i n g s . F i r s t , there a r e i n v e s t i g a t i o n s o f t h e r o l e o f s t o m a t a as t h e p o r t s o f e n t r y o f p o l l u t a n t s , w h i c h have u s u a l l y t a k e n i n t o a c c o u n t s t o m a t a l a p e r t u r e s a t d i f f e r e n t t i m e s o f day and u n d e r different conditions. S e c o n d l y , t h e r e a r e s t u d i e s whose m a i n c o n c e r n has b e e n t h e r e a c t i o n o f t h e s t o m a t a to t h e p r e s e n c e o f a i r p o l l u t a n t s , and t h e c o n s e q u e n t e f f e c t on w a t e r r e l a t i o n s and t h e p h y s i o l o g y o f t h e p l a n t g e n e r a l l y . " Much o f  the  earliest  work  on p l a n t  response to  ozone  18  r e c o g n i z e d the p o s s i b l e importance indirect  evidence f o r  extent  of  ration  ratios  in  Bobrov  (1952)  and J u h r e n et  pattern bands  injury.  their  of  leaf.  to  (1968)  only  plant.  route,  and o n l y  the  first  is  of  of  this  (1959)  injury  the  surface).  leaves  (the  the  Valli  not  just  similar other at  is  the  unique,  Indirect  the  little  evidence.  c o a t i n g the  lower  beans a r e  c o a t e d the  upper  l o c a t e d on of  from exposures  and i n v o l v e s  c o a t i n g the  entire  I  am unaware  of  separate diffusion  features  evidence that  of  of  any e x p e r i m e n t s  epidermis, using  stomatal  pathways  from  into  leaf,  any  other  stomata  on  surfaces  underside  them c o m p l e t e l y  the  indisputable,  complete  stomata.  examine  into  evidence of  m e c h a n i c a l means t o  to  both  this  p o s s i b l e pathways  all  factors  ozone e n t r y  u p p e r and t h e  (1971)  and p r o t e c t e d  stomata  l a n o l i n had no e f f e c t  stomata o f p i n t o  t o up t o s e v e n ppm o z o n e , b u t protection  of  showed t h a t  whereas  of  s t o m a t a were  conclusion is  injury,  c o a t i n g both  role  banding  stomatal  environmental  route,  of p i n t o bean l e a v e s w i t h  prevented  the  injury.  examination.  the  surface  tobacco  the  s u p p o r t e d by r e m a r k a b l y  H e g g e s t a d and M i d d l e t o n  lower  the p r e d i c t i o n o f  concluded that the  the  used e v a p o t r a n s p i -  (1957) n o t e d t h a t  rigorous  i n a review  The s e c o n d p a r t  while  al.  (1964)  for  gathered  in determining  G e n e r a l l y , however,  i n f l u e n c i n g ozone i n j u r y , the  al.  and  g r a s s e s c o r r e s p o n d e d to  has been a c c e p t e d w i t h o u t Heck  et  equations  smog i n j u r y  on t h e  involvement  Macdowall their  of stomata,  are  the  or  p o s s i b l e pathways. the  only route  of  19  ozone e n t r y variation partial  comes f r o m e x p e r i m e n t s  affords  stomatal  importance of comes  and i n j u r y , degree of  partial  protection,  closure.  The o n l y  the  f r o m the  where  stomatal  nature  a,type  of  of  pathway  the  of  i n such  the  relative  experiments  c o r r e l a t i o n between  a n a l y s i s which allows  for  aperture a  large  uncertainty.  may n o t be c o n s t a n t , involvement  content  c o r r e s p o n d i n g to  test  Under c h a n g i n g c o n d i t i o n s , t h e  on t h e  environmental  in  the  of  importance of  as i n d i c a t e d by t h e work stomatal  response of  behavior  t o b a c c o to  of  Lee  and l e a f  ozone.  stomata (1965)  sugar  Lee  says,  "The r e l a t i v e i m p o r t a n c e o f s t o m a t a l w i d t h to l e a f s u s c e p t i b i l i t y i s d e t e r m i n e d by o t h e r c o n d i t i o n s o f t h e l e a f and p e r h a p s a l s o by ( t h e ) c o n c e n t r a t i o n o f ozone t o w h i c h the l e a v e s a r e e x p o s e d . . . l e a v e s w i t h open s t o m a t a i n t h e i n i t i a l s t a g e o f ozone t r e a t m e n t b u i l d up a t o x i c l e v e l o f ozone i n t h e t i s s u e s o o n e r t h a n t h o s e w i t h the s t o m a t a c l o s e d ; b u t the c o n c e n t r a t i o n o f ozone i n t h e l e a f n e c e s s a r y to p r o d u c e v i s i b l e symptoms depends on o t h e r c o n d i t i o n s o f the l e a f . . . l e a v e s w i t h open s t o m a t a w o u l d have more damage t h a n t h o s e w i t h c l o s e d stomata. T h i s m i g h t be the c a s e u s u a l l y o b s e r v e d i n t h e field. However, s t o m a t a l c l o s u r e c a n n o t p r e v e n t damage f r o m ozone when t h e c o n d i t i o n s w i t h i n p l a n t t i s s u e s a r e f a v o r a b l e f o r ozone i n j u r y a n d t h e c o n c e n t r a t i o n o f ozone i s h i g h . " The r e l a t i v e  importance of  environmental resistance, total  leaf  s t o m a t a may a l s o be a f f e c t e d  v a r i a b l e s which a f f e c t  s u c h as w i n d v e l o c i t y , resistance  resistance  (R- )  Mansfield,  1977).  s  The e n t i r e  (R^)  boundary  and t h u s  which i s  area  of  layer  the  percentage  c o n t r o l l e d by  (see T i n g and H e a t h ,  environmental  1975;  by  of  stomatal  A s h e n d e n and  variation  and i t s  effect  20  on ozone s u s c e p t i b i l i t y was summarized by Treshow who n o t e d t h a t  the environmental  stomata "appeared to exert response  to p o l l u t a n t s , "  meteorological  v a r i a b l e s which  the g r e a t e s t  and t h a t  and e d a p h i c f a c t o r  (1968)  review  presumed t o have light  (quality,  concentration, nutrient  prior  humidity,  influence  "virtually  every  of plants  effect  influences  to o z o n e . "  on p o l l u t a n t  and i n t e n s i t y ) , wind,  and s o i l  on p l a n t  some o f t h e f a c t o r s w h i c h were  an i m p o r t a n t duration,  levels,  were f u r t h e r  listed  influence  i n the environment  t h e p r e d i s p o s i t i o n and s e n s i t i v i t y Heck's  (1970)  t e m p e r a t u r e , CC^  s o i l moisture,  texture.  response:  A l l these  s u b d i v i d e d a c c o r d i n g to t h e i r  soil  aeration,  conditions  effects  either  to or d u r i n g e x p o s u r e . D u n n i n g and Heck  intensity,  (1977)  temperature,  examined t h e e f f e c t  and r e l a t i v e  humidity  r e s p o n s e o f b e a n and t o b a c c o t o o z o n e .  of  light  on t h e  They c o n c l u d e d ;  "we b e l i e v e t h a t t h e v a r i o u s i n t e r a c t i o n s a s s o c i a t e d w i t h e x p o s u r e e n v i r o n m e n t s a r e t r i g g e r e d p r i m a r i l y by a change i n s t o m a t a l a p e r t u r e a s s o c i a t e d w i t h changes i n l e a f water p o t e n t i a l , " and t h a t  the  ' V a r i o u s i n t e r a c t i o n s a s s o c i a t e d w i t h growth e n v i r o n m e n t s ( p r i o r t o e x p o s u r e ) a r e t r i g g e r e d p r i m a r i l y b y changes i n l i p i d c o m p o s i t i o n and membrane s t r u c t u r e . " Their paper, aperture, membrane  however,  leaf  c o n t a i n e d no measurements  water p o t e n t i a l ,  stomatal  composition, or  structure.  T h e r e i s a good d e a l includes  lipid  of  of e v i d e n c e , however,  measurements o f s t o m a t a l  aperture,  which  w h i c h shows  that  21  environmental protection  changes may i n d u c e b o t h  f r o m ozone i n j u r y  (1972) p a i n t e d  the  primary  ten m i l l i g r a m s  per  liter  e x p o s e d them aperture  to  0.20  to  (751  exposure  leaves.  leaves,  Apart changes  leaves,  for  addition  to  experiment d i d not  represent  that  as  temperature  more  for  likely  protection. cultivar  to  reveal  w o u l d be more  to  to  other  the  of  that  a coating  like  likely  to  in  in  an  within  the  did serve  ozone  between  to  show,  injury. such  variable closure  s u c h as age  show t h a t  authors  t e n mg 1 ^ ABA  added ABA (or  factor  leaves.  effects  (the  such  as an i n d e p e n d e n t  a complex  leaves  4.9  and RNA  variation  The. e x p e r i m e n t  factor  Ozone  physiological  to  of  4. 2 /A  untreated  stomatal  protein  a close relation  The use o f  to  in ABA-treated  one c o u l d o b j e c t  or humidity)  in  10.7  c l o s u r e may r e d u c e  a simple  Stomatal  chlorophyll  ozone p r o t e c t i o n  an e n v i r o n m e n t a l  stomatal  The use o f  2.9^  addition  o f .expected changes .  however,  to  from  q u e s t i o n of whether  grounds  and  i n both A B A - t r e a t e d  w i t h measurements  on the  (ABA)  controls  greater  al.  with  three h.  (yuJ) i n  and  et  in ABA-treated plants).  equivalently,  chlorophyll),  acid  as m e a s u r e d by  closure  responsible  this  abscisic  e x p o s u r e , was  i n d u c e d by ABA i n  were p a r t i a l l y  of bean p l a n t s  microns  and from 4.2  from t h e  closure  Fletcher  ppm ozone f o r  Injury,  induced stomatal  untreated  region  (mgli^)  more c h l o r o p h y l l  and u n t r e a t e d  tested  leaves  0.40  e x t r a c t i o n six days a f t e r plants  concurrently.  d e c r e a s e d from 1 0 . 7  in ABA-treated  stomatal  stomatal  things is and  or closure,  22  when and i f  it  protection.  did occur, is  O.ther  experiments  w h i c h a r e more l i k e l y represent  only a p a r t i a l  than  possible field  explanation  have u s e d s i m p l e  a coating of  situations,  factors  t e n mg 1  ABA to  1  and n a t u r a l  protective  mechanisms. Quite  • a few w o r k e r s  increases with  have shown t h a t  i n c r e a s i n g humidity  1952;  Thomas and H e n d r i c k s ,  Davis  and Wood, 1973;  cases  (e.g.,  Otto  1956;  ozone  (Menser, Otto  It  1971; of  1969)  S c h u l z e et  water  this  and Went,  1969;  has b e e n shown t o  1972), it  The  stomatal  response is  effects  "peristomatal al.,  Hull  on t h e  loss  transpiration,"  or,  if  the  not  humidity  entirely  of  water  (Lange e t  al.,  exposure  c o u l d be m e d i a t e d by changes  is in  potential.  Additional  single  factors  s t u d i e d , w i t h the  inclusion  c o n c u r r e n t measurements o f R , w h i c h show a c l o s e  inverse  relation  concentration nutrition In  R  s  between R  (Mansfield  (Leone,  and ozone i n j u r y ,  g  and M a j e r n i k ,  the  variables  CO2  and p o t a s s i u m  use o f more complex f a c t o r s  has a l s o d e m o n s t r a t e d a c l o s e  and ozone s e n s i t i v i t y .  noted that p l a n t s  1970)  include  1976).  some c a s e s ,  independent of  humidity  direct  l o n g enough d u r a t i o n ,  leaf  of  this  may i n v o l v e  from guard c e l l s ,  1962;  Leone and B r e n n a n , 1969), and i n some  and D a i n e s ,  mechanism i n v o l v e d i n  .  sensitivity  and D a i n e s ,  be c l o s e l y a s s o c i a t e d w i t h d e c r e a s i n g R .  clear.  of  grown i n  Siedman and R i g g a n  as correlation  (1968)  c o n t r o l l e d environments had a  23  reduced s e n s i t i v i t y and showed t h a t whereby  of  this  stomatal  environmental  to  c o r r e s p o n d e d to  aperture  varying  c o r r e s p o n d e n c e between  et  al.  the  Dean  size  factors  of  was n e v e r  the  variation  of  cotton  where s e n s i t i v i t y T i n g and Dugger found t h a t  the  c o r r e s p o n d e d to expansion of Dugger dark  periods  changes  factor."  (1968).  the  al.  and f o u n d a good and  density.  injury  with  Tingey  age  In  injury  after  20  days  complex  external  Evans and T i n g  (1974a)  of  leaves  the  primary  sensitivity  Similar to  of  was a  exchange  results,  on  ozone w i t h p l a n t  the age,  Glater  et  al.  ozone s u s c e p t i b i l i t y  in  tobacco  contrast,  onset of  (1962)  in  c o r r e l a t e d w i t h R , were f o u n d by  intracellular et  six  c i r c u m s t a n c e s , and gas  was n o t  of  cultivars  "bean l e a f  sensitivity  stage  l o o k e d at  of  use o f  sensitivity  internal  limiting  of  in R .  results.  bean w i t h age and f o u n d t h a t f u n c t i o n o f more  independently  and s t o m a t a l  a decrease in  show c o n t r a s t i n g the  rhythm  s o y b e a n and f o u n d a g o o d '  s t u d i e s b a s e d on the  s t u d i e d changes i n  (1972)  variation  f r o m s e e d i n g and an i n c r e a s e Other  winter,  i n c r e a s i n g ozone s e n s i t i v i t y  leaf  c o r r e s p o n d e n c e between  the  an endogenous  ozone s e n s i t i v i t i e s ,  s t u d i e d the  trifoliate  during  was r e d u c e d ,  i n both stomatal  (1973a)  first  pollutants  conditions.  tobacco, of  increases  air  functional  stomata  and  (1962)  the  spaces. s t u d i e d the  on ozone s e n s i t i v i t y  i n ozone s u s c e p t i b i l i t y  effect  of  pre-exposure  i n bean and showed  i n d u c e d by t h e s e  that  treatments  24  had no  direct  opening  relationship  d u r i n g exposure.  i n j u r y were a f u n c t i o n plant  at the time  increased action  They s u g g e s t e d  of carbohydrate  of exposure,  susceptibility.  of carbohydrates  preventing in  t o the d e g r e e  oxidation  the c e l l  The  authors  literature,  that  to o c c u r , b u t  that  that,  the p r i m a r y  factor  changes i n  r e s e r v e s i n the  e x p l a i n e d by  the compounds,  compounds as p r o t e i n  r e v i e w o f the  beyond  that  a source of reducing  o f such  membranes.  stomatal  whereby d e p l e t e d r e s e r v e s  T h i s was  as  of  concluded, based  stomata  must be  on  a  open f o r  "stomatal opening  in predisposing plants  ItCpid  and  injury  i s not  to i n j u r y  from  ozone." In c o n t r a s t Ting  and  Dugger  t o t h e work o f Dean (1971) a l s o  sensitivity  between two  but  d i d not  find  and  stomatal s i z e  it  s h o u l d be  and  tobacco  a similar  the d i f f e r e n c e  cultivars,  Dean's s e r i e s  c o n t a i n e d B e l W3  a generally higher  lower  transpiration  i n B e l B and  suggested  cultivar,  t o them t h a t  cultivars, Ting balance,  smaller roots  In t h e l i g h t ,  l e a f water p o t e n t i a l s d i f f e r e n c e s might  R^  were l o w e r , be  W3,  susceptibility  i n water  B e l B, had rate.  Bel  b u t n o t B e l B.  Dugger d i s c u s s e d a more g e n e r a l change tolerant  of  above,  i n ozone  B e l B and  r e l a t i o n s h i p between  o r density'.  noted,  whereby t h e i r  stem  studied  (1972) m e n t i o n e d  and  was  which  ascribable  to  conductance. Turner  e t a l . (1972) s t u d i e d  ozone s e n s i t i v i t y  i n four  tobacco  the r e l a t i o n s h i p cultivars,  o f R^  B e l W3,  and  6524 (a  25  tolerant  (cultivar),  and two c u l t i v a r s  tolerance  (Conn 49 and 6 590) .  generally  related  of s e n s i t i v i t y ,  in  study  relationship (in  of  stomatal  the  are not s u f f i c i e n t  in visible  Mansfield  (1973)  aperture  exposure  Despite al.,  on ozone i n j u r y , stomatal  some i n d i c a t i o n s  1974a),  on s t o m a t a ,  was l e s s  to o z o n e . "  that  Koritz  equivocal.  work  the e f f e c t He s a i d ,  (1952)  smog.  This  are of during  80% i n tomato  effect  irreversible  o f ozone "stomata  et  exposure close  c l o s u r e has come of a i r  plants  after  therefore,  in from  pollutants transpiration exposure  vapors.  over  was n o t r e v e r s i b l e  closure,  ( s e e Dugger  showed t h a t  o f two h p e r day o f t h a t m i x t u r e ,  artificial  "the balance of  of plants  o f 0.1 ppm ozone and 1 - n - h e x e n e  this  effect  Mansfield's conclusion  on t h e e f f e c t s  and Went  was r e d u c e d by a b o u t  found t h a t  "differences  to the  apertures  Evidence f o r this  some o f t h e e a r l i e s t  doses  the  to the c o n t r a r y  to the second a r e a ,  a mixture  this  pollutants."  with regard  on p l a n t s .  used  to account f o r  the s e n s i t i v i t y  1962; Evans and T i n g ,  response  in  concluded, with respect  i n determining  to a i r  cultivars  damage."  evidence suggests that  importance  some a n o m a l i e s  l e d them t o c o n c l u d e t h a t  stem c o n d u c t a n c e )  differences  i n comparing the  but the i n t e r m e d i a t e  demonstrated  which  intermediate  They f o u n d t h a t R^ was  t o ozone s e n s i t i v i t y ,  extremes their  o£  four  With days,  upon r e m o v a l  was somewhat  to daily they  of the  26  different by H i l l  from the r e v e r s i b l e  and L i t t l e f i e l d  exposed a l a r g e tobacco,  pinto  cauliflower,  closure  t o be l a r g e l y  Another  tolerant  moisture  ppm t h e y  cultivar,  and f o u n d o f the  c l o s u r e , the Littlefield  term dampening f o u n d by K o r i t z and  type  (e.g.,  reversible  Macknight,  ozone  1968)  result  effects  o f ozone-  o f damage  type  further  (1972) , i n two c u l t i v a r s  of  i n the c l o s u r e r e s p o n s e under  conditions.  U s i n g 60 min e x p o s u r e s t o 0 . 2 0 -  found c l o s u r e w i t h i n  while  o f c l o s u r e was  C o n s o l i d a t e d L and s e n s i t i v e B e l W3.  They s t u d i e d t h e v a r i a t i o n s  0.25  stomatal  doses.  f o u n d by H i l l , and  c h a r a c t e r i z e d by R i c h and T u r n e r  different  that  tissue.  The s h o r t - t e r m  tobacco,  and f o u n d  encompass t h e b a s i c forms o f d i r e c t  epidermal  corn,  upon r e m o v a l  i n d u c e d c l o s u r e may o c c u r as an i n d i r e c t to  chard,  of ozone-induced stomatal  and t h e l o n g e r  on s t o m a t a .  wheat,  i m p r e s s i o n s ) and  reversible  repeated  r e v e r s i b l e " type  (1952)  barley,  e x p o s u r e s , one t o two h ,  two t y p e s  short-term  Littlefield  and t o m a t o ,  leaf  found  d e c r e a s e s i n p h o t o s y n t h e s i s and t r a n s p i r a t i o n .  but d i d not give  These  Went  potato,  (as measured by p l a s t i c  these' e f f e c t s  and  as low as 0.1 ppm c o u l d c a u s e p a r t i a l  They u s e d s h o r t - t e r m  (1969)  Hill  l i m a b e a n , bush b e a n ,  sugar beet,  complementary  ozone,  (1969).  number o f s p e c i e s , o a t s , bean,  concentrations  c l o s u r e i n d u c e d by ozone  t e n min i n t h e  c l o s u r e i n the s u s c e p t i b l e c u l t i v a r  tolerant occurred  27  much more s l o w l y . the  ozone.  This  atmospheres, atmosphere slowly,  371  and the  relative  was  humidity  stomata  r a t e was  plants,  kilopascals  seconds per  centimer  (RH).  for  the  with a leaf (kPa),  after  of  -5.4  bars  in  the  plants  to  the  dry  showed t h a t in  to both h i g h e r response  to  in  be c o n s t a n t ,  g  degree  The f a c t provide  the  of  R  the  than  the  stomata  This  In  the  plants  stomatal  stomata  authors  basis for  to  water  had a h i g h e r r e s p o n s e to  to  to  potential  8.4  s e c cm ^  bean  a  dry respond  initial  R  s  be  lower  attributable of  closure  in  relationship  of  ozone n e e d Leone  initial ozone  R  g  not  (1976), and a  fumigation.  r e s p o n s e to  from acute  at  in  conclude that  degrees  experiments  protection  -3.2  5.2  d i d not  complementary  closure in  of  stomatal  with a leaf  and g r e a t e r  g  In  t e n min e x p o s u r e  atmospheres might  closure in  that  to  and c l o s u r e i n r e s p o n s e t o  however.  potassium-deficient lesser  dry  fumigation. R  2.5  a l s o had a h i g h e r  leading  initial  initial  found that  closure occurred in  atmosphere  Bean p l a n t s  injury  c l o s e d more  w h i c h c l o s e d f r o m 2.9  although  atmosphere, of  a moist  Experiments with well-watered  a moist  ozone.  amounts  between  kPa),  same p e r i o d .  atmosphere, all  (-540  plants,  dry  water p o t e n t i a l  0 . 2 0 - 0 . 2 5 ppm, w h i c h was more s l o w l y  of  two. c u l t i v a r s .  c l o s e d from  ( s e c cm ^)  in water-stressed  In  to  of both c u l t i v a r s  equal  closure  upon' r e m o v a l  limited  w i t h b e a n s , R i c h and T u r n e r  of w e l l watered -320  c l o s u r e , however,  (73I;RH),  experiments  bars,  C l o s u r e was r e v e r s i b l e  ozone  ozone may exposure  28  was p o i n t e d the  out by E n g l e and Gableman  response of  o n i o n to  0.3  differentially  ppm ozone f o r  ozone t o l e r a n t  lines  TDYG and SW34,  they  sensitive  30-60 m i n .  W4 and SW52, found that  differences  ozone.  of  tipburn  and p o t t e d indicated factor,  bulbs that  and t h e i r  was  loss.  found to  ozone, while of  90 min o f to  recover.  during  i n W4 o r  fumigation  at  to  the  a rate  in  ozone t o l e r a n t  lines  Fl  hybrids  genetic The  SW34,  three  air,  ozone was  was  hybrid  0.4  ppm rate  removed  ozone to  a low  ppm o z o n e , tolerant  five  After  times  closure  a rate  An a v e r a g e  after found  power  and  it  lines slower  one c y c l e o f  however,  40 min t o  to  t r a n s p i r a t i o n - was  o c c u r r e d at  response.  observation  W4 x SW34  exposure  w i t h 0.3 in  by  lines  study  the•transpiration  If  darkness.  in ozone-free  darkness  r e s p o n s e to  gene p a i r .  i n W4 and the  closure  a s e c o n d ozone e x p o s u r e  equal  susceptibility  and t h e i r  laboratory,  30. min o f  lines  field-planted  a dominant  the  same e x p o s u r e .  r e s p o n s e to  and r e o p e n i n g to  after  stomatal  occurred i n i t i a l l y in  in  S t o m a t a were a l s o o b s e r v e d u n d e r  found t h a t  closure  in  t h e r e was no change the  the  F l h y b r i d s were a l s o u s e d t o  ozone,  of  susceptible  in  lines  was  lines  stomatal  injury  inbred  Transpiration  fumigation  microscope was  to  decrease  SW34 g i v e n  in  c o n t r o l l e d by a s i n g l e  stomatal'response of water  these  ozone t o l e r a n c e  perhaps  W4 and SW34,  of  compared  Working w i t h  differences  to  They  inbred  and the  were c l o s e l y r e l a t e d Observations  (1966).  in  than  closure response  approximately  cycle for  c l o s e upon t h e  the  first  /  29  exposure, min t o  t e n min t o  r e c l o s e upon r e f u m i g a t i o n ,  Stomata  of the  injury  symptoms.  This  two h p e r i o d p r i o r  type  interaction evident  of  that  considered,  in  the  in  A l t h o u g h the  instructive  in  terms  the  of  one t o l e r a n t  found s i g n i f i c a n t  sensitivities.  Speed o f  volume o f  were s i g n i f i c a n t l y and d r y  exchanged  kinds  of  used i n  the  effects  In  between  differences  of  dry  the  the is  which initial  stomatal  in  the  closure  air,  initial  of  SC^ s u s c e p t i b i l i t i e s  With c o n t r o l l e d  between  be  A survey  and one s e n s i t i v e ,  stomatal  different  of  fumigation.  exposures however,  stomatal  different  SG^  fumigation  cultivars, the  size  i n r e s p o n s e to S C ^ ,  gas e x c h a n g e d d u r i n g t h e  a percent  must  S O ^ , t h a t work  accounted for  atmospheres.  (as  factor  considerations  relationship  b e h a v i o r w h i c h c o u l d have  wet  (1977) was  and SC^ s e n s i t i v i t y .  al.  This  Pelargonium with varying  cultivars,  and t o t a l  ;  i n a comparison of  r e v e a l e d no s i g n i f i c a n t  significant  pollutant  and c l o s u r e i n r e s p o n s e t o  two  a  is  c o m b i n a t i o n w i t h changes i n  al.  Bonte' et  e x p o s u r e s , and i t  e x p o s u r e s may have  B o n t e ' et  of  all  importance  of  frequency  c l o s e at  r e s p o n s e may be o f  aperture.  or  reopen.  visible  c l o s u r e response i t s e l f .  of  ten  of  however,  11 c u l t i v a r s  ozone,  appearance  experiments  aperture  d i d not  s u b - a c u t e and a c u t e  may be i m p o r t a n t  the  the  repeated  on the  stomatal  of  to  of  and 20 min to  s u s c e p t i b l e SW34 p l a n t s  within  effect  r e o p e n upon r e m o v a l  total  in  both  volume  p o s s i b l e , volume w i t h o u t  any  30  stomatal  closure)  treatment, the  whereas  final  dry a i r  differed it  d i d not  mean a p e r t u r e s  they  did not.  between  of  This  c l o s u r e o c c u r r e d to  although also.  the  initial  Two r a t i o s  and t o t a l i n wet  i n wet  cultivar,  were  air.  initial  the  that  that  e x p o s u r e to  aperture 40%,  dry  difference  In wet  air,  differed,  the  end p o i n t  air/aperture air/total in  i n wet  sensitivity  sensitivity  humidity  apertures  at  to  to  (19 70)  SC^ c o u l d c a u s e an i n c r e a s e i n  and a d e c r e a s e i n s t o m a t a l  airi',  the S C ^ - s e n s i t i v e  differential  relative  did  volume e x c h a n g e d  M a n s f i e l d and M a j e r n i k  i n atmospheres of  air  same end p o i n t .  SC^ was a c c o m p a n i e d by a d i f f e r e n t i a l atmospheric humidity.  the  in  fact  i n dry  the  whereas  and t h e  s i g n i f i c a n t l y higher  indicating  air,  aperture  apertures  (aperture  and SG^  In wet  indicated that  volume exchanged i n d r y  air)  control  stomata d i f f e r e d ,  was due t o b o t h a d i f f e r e n t that  the  found  stomatal  greater lower  than relative  humidities. While humidity present  the  interaction  and s t o m a t a l the  between  r e s p o n s e to  same c o m p l e x i t i e s  stomatal  ozone does n o t  as t h e  response  and SO^ r e s p o n s e , b o t h t h e  response  to  have the  ozone and t h e  important effects  on a c u t e  i  of  final  implications  for  interaction rate  aperture the  growth.  of  appear of  closure  during  relationship  ozone on s t o m a t a l b e h a v i o r  s u s c e p t i b i l i t y and  r e s p o n s e to  and i t s  to  humidity in  fumigation between effect  31  Growth Changes exposure changes of  to  in  stomatal  low  levels  in plant  stomatal  changes  filtered  exposures  air  of  a mixture of  the  that  fruit  air  treatment  both  the  air  versus  occurrence  The ambient  al.  (1969)  versus u n f i l t e r e d  ambient  yield  0.25  oxidant  of  oxidants  in  and i n oxidant  the  (1967)  use  and a p p a r e n t  California  growth  (prunings)  in  environment al.  content  reported  season i n  the  sugar  of  were  their  content  leaves  as a  exposure.  showed t h a t  (1972a)  in  that  growing  reductions  chlorophyll  reduced y i e l d  al.  the  reported,  open-top  levels  and v e g e t a t i v e  ppm d u r i n g  Thompson and T a y l o r  Barnes  Thompson e t  They a l s o r e p o r t e d  of  Work w i t h  demonstrated  result  physiological  ozone and PAN, and Thompson e t  up t o  of b e r r i e s  other  ozone and w i t h a m b i e n t  filtered  grapevines.  of  to  plants,  treatments,  reduced both  result  of  as a d i r e c t  effects.  basis  chamber  study.  either  as a r e s u l t  t r e a t m e n t s has  On p e r e n n i a l  peaks  or  long-term  ozone may be a c c o m p a n i e d by  productivity,  effects  s u c h growth  of  of  i n d u c e d by  i n d u c e d by ozone e x p o s u r e .  controlled  on t h e  behavior  (1969) in  this  lemon and o r a n g e ,  ambient  photosynthesis  reported  showed t h a t  oxidants in  decreases  those  same  and Thompson et  reduced both same  water  species.  in photosynthetic  rate  32  after for  exposure  five  to  increases pine  of pine  eighteen  while  (Barnes,  Feder  and F e r r y  151. was  Long-term  the  corollary-  exposure  ascorbic acid  day,  for  carbohydrate  h per  t  the  one to  duckweed  ambient  exposure  seed y i e l d s to  in  0.10  day,  for  (Feder  to  14  days,  and  a reduction  ambient  The o v e r w h e l m i n g ozone e x p o s u r e  on p l a n t  above,  has  growth  in  effect  on v e g e t a t i v e  growth,  found decreases r e s p o n s e to  ground p o r t i o n s  of  flowering  like  in  growth plant  into have  the  to  flowering,  petunia, with  Coast.  and  effects  below-ground  of  described reproductive  subdivide  generally  ppm  in y i e l d  those papers  Attempts  to  (1972)  the work on the  in both vegetative  ozone.  the  of  five  while  ozone on the A t l a n t i c  majority  1974).  inhibited  Craker  and H e g g e s t a d  exposed to  al.,  0.10  1969)  of  by  carnation,  totally  showed an o z o n e - i n d u c e d r e d u c t i o n demonstrated  et  reduced  and S u l l i v a n , 50%.  cotton  loxv ozone  E x p o s u r e to  f r o n d d o u b l i n g r a t e by  (1973)  of  ppm o z o n e ,  geranium  length.  oxidants  (Heagle  three months,  size  internode  ozone f o r > f i v e  potato  of  content  and s e e d y i e l d  exposure  and l e a f  increasing  in  showed t h a t  lint  reduce  showed t h a t  side branching,  flowering  (1974)  soybeans, long-term  shown to  (1970)  reducing  showed  ppm ozone d e c r e a s e d t h e  r e d u c e d the  In  seven h per  while  0.05  0 . 0 5 - 0 . 1 0 ppm ozone  He a l s o  rate.  increasing  in California  levels  to  to  1972b).  Brewer  about  weeks.  in respiration  seedlings  content  seedlings  the  and above-"  shown a  greater  33  effect  on r o o t  reduction tobacco, water  in  growth.  the  top and r o o t  b u t p o i n t e d out  loss  due t o  0.10  days p e r week,  the  for  top f r e s h weight by 25%, w h i l e  al.,  1971),  eight  al.  effect  Treatment  on r o o t  and R u n e c k l e s  and s u g g e s t e d t h a t  with  root  growth i n r a d i s h  reduced  (1977)  growth,  dry  levels  (Tingey  as compared t o  20%  showed t h a t  et  for  root  growth  i n c l o v e r and r y e g r a s s ,  reductions in  0.03  or  t o p growth  0.09  ppm  were  assimilation  of  growth o r r o o t  showed t h a t  19% f o l i a r  20% f o l i a r  injury  to  ozone  growth may  injury  exposure, (on  The r e p e r c u s s i o n s  species.  evidently  Wilhour  i n western  dry  and white  in foliage  i n Ponderosa pine  growth r e d u c t i o n s o n l y i n r o o t  determined  foliar  s i g n i f i c a n t growth r e d u c t i o n s o n l y  while  significant  on f o l i a r  and s e p a r a t e l y .  even i n c l o s e l y r e l a t e d  (1977)  l e d to  weight,  both together  injury  vary widely, Neeley  growth was a r e s u l t  e x p o s u r e , by e x p o s i n g l e a v e s and r o o t s  foliar  pine  and f o u n d  low ozone  (1977), working with soybean,  reduction in root  whole p l a n t s ) of  five  (NAR). Blum and T i n g e y  not  day,  growth,  a c c o m p a n i e d by a c o m p e n s a t o r y i n c r e a s e i n n e t  that  (1973b)  f r e s h weight  growth r e d u c t i o n s i n d u c e d by e x p o s u r e t o  rate  also included  d r y w e i g h t was r e d u c e d by 21% and t o p  was more s e n s i t i v e t h a n t o p  ozone,  B e l W3  h per  t h r e e weeks o f  50% r e d u c t i o n i n r o o t s  Bennett  of  T i n g e y et  ppm ozone f o r first  f o u n d an e q u a l  f r e s h weight  lesions.  by o n l y n i n e p e r c e n t .  leaves.  to  top  r e d u c e d by 21% and r o o t  root  a l s o had' a l a r g e r  a l . (1973)  f r e s h weights  that  injury  e x p o s e d s o y b e a n to  weight  Heagle et  led  weight.  to  dry  34  Bennett  and Oshima ( 1 9 7 6 ) , w o r k i n g w i t h  found that  r o o t s were more s e n s i t i v e  reductions  resulting  that  experiment,  in  effects of  et  al.  on growth  the p r e s e n c e of  (1974)  reviewed  and p o i n t e d o u t  growth by ozone c o u l d r e s u l t  filtered  controls.  than leaves  from o z o n e - i n d u c e d f o l i a r foliar  and l e n g t h were i n c r e a s e d , a l t h o u g h Bennett  In  of a charcoal f i l t e r  air  leaf the  that  literature apparent  controls filter  there  is  a d a p t e d to  true  always  to  the p l a n t .  effect  the p r e s e n c e o f  the  these  grown i n c h a r c o a l - f i l t e r e d  examples o f n o r m a l g r o w t h .  controls  is  when i t  to p l a n t s  amount o f filtration  ozone,  with  the  effect.  does n o t  have a d a p t e d to  In  the . c h a r c o a l  remains  represent  are  plants  comparing plus  represent  charcoal-filtered a small  the p o s s i b i l i t y t h a t a control,  if  have  constituents,  would not  air  In  charcoal-filtered  atmospheric air  addition  often  experimental  receiving filtered  there  not.  s h o u l d more  p o s s i b i l i t y that  If  was  stimulations  experiments,  treatments the  number  on ozone  removing atmospheric c o n s t i t u e n t s which  advantageous  plants  is  In  leaf  dry weight  a c c u r a t e l y be c o n s i d e r e d a c h a r c o a l f i l t e r air  growth-  injury.  injury,  to p r o v i d e " c l e a n " a i r  ambient  to  from comparison w i t h c h a r c o a l -  pollution  c o n s i d e r e d an ozone o r o x i d a n t  comparison of  carrot,  charcoal  plants,  a low a t m o s p h e r i c ozone l e v e l  over  the  35  course  of  natural (1974) with  e v o l u t i o n or d e l i b e r a t e  sources of  ozone.  suggested, t h i s  filtered  air  increased t o t a l and t o p  dry weight  generally  of  a growth  and a p r o t e c t i v e  two  time s c a l e s .  effect  forms  of  Comparing f i l t e r e d 0.03  in barley  The g e n e r a l  effect of  q u e s t i o n of whether  retarding  ppm ozone  i n d u c e d by  effect.  None o f  directly  to  growth  growth  the  effects  two  a  different  between of  the  more  sub-acute  dampening r a i s e s  effect,  e x i s t i n g work  of  aspects of  treatment,  effect  would tend to  concerns of  growth  the  s t i m u l a t i o n may a l s o be  a s s o c i a t e d w i t h some s t o m a t a l although t h i s  two  over  relationship  a growth  opening,  are  low ozone  and a l o n g - t e r m s t o m a t a l  the  air  and s m a r t w e e d ,  stimulation  acclimation,  commonly o b s e r v e d growth  on a c u t e  al.  on s u s c e p t i b i l i t y whereby b o t h a  beneficial  reflecting  the  et  e x p o s u r e s u g g e s t s one a s s o c i a t i o n between  stimulation  of  Bennett  to  i n bean.  and e f f e c t s  exposure  of  possibility.  plant  The'possibility  effects  The d a t a  p l u s ozone, exposure to  dry weight  sub-acute  s e l e c t i o n due  this  in  perhaps  stomatal  d e c r e a s e the this  thesis,  area speaks  the  relationship  s u b - a c u t e exposure to  s u s c e p t i b i l i t y and s t o m a t a l  protective  behavior.  the  effects  36  Materials  Bean and  Mint  Bush bean planted soil.  two  after  experimental  a r v e n s i s L.) i n the  sand f o r  plastic  of  environment day/night,  five  use.  an e i g h t  to  Axillary  1).  s i x h per  day  p l a c e d w i t h i n the  periodically  during experiments Federal Register,  stock  (8 AM t o AM t o  5 PM).  1% NBKI  November 25 ,  u s i n g compressed a i r  in  by t h e  rooted  t e n cm to  controlled  7 PM).  chambers. Meters against  in  degrees C e l s i u s  compressed a i r  d i o x i d e was d e t e c t a b l e ,  Mint  days p r i o r  All  (C) ozone  Ozone was  or oxygen  and was m o n i t o r e d w i t h Mast  ozone m e t e r s  no n i t r o g e n  (11  immediately  Stem c u t t i n g s were  20/15  w i t h an 11 h p h o t o p e r i o d  experiments  uniform  in pasteurized s o i l  at  retained  day i n t e r v a l .  E x p e r i m e n t s were done i n  chambers m a i n t a i n e d  a corona discharge tube,  pasteurized  began e i t h e r  s h o o t s . , were removed f o u r  experiments,.  the  in  was  s e e d l i n g s were  fourteen  (Fig.  g e n e r a t e d by p a s s i n g a s t r e a m o f  In  seeds per p o t ,  came f r o m a g e n e t i c a l l y  greenhouse  e x p o s u r e s were f o r  method o f  c v Pure G o l d Wax)  Treatments  two weeks and p o t t e d  pots.  start  to  L.  e m e r g e n c e , one o r two u n i f o r m  for  maintained  the  two  sowing or a f t e r  (Mentha  in  (Phaseolus v u l g a r i s  cm d e e p ,  After  per pot  and Methods  were  through  (Model  724)  calibrated  a c c o r d i n g to  1971. ozone  generation,  method o f  Saltzman  the  37  Figure  3- A c u t e f u m i g a t i o n for transpiration ment  chamber measure-  38  (1954),  at  any o f  the  ozone c o n c e n t r a t i o n s  experiments.  No ozone was d e t e c t e d  supplied with  filtered  vary,  55 and 801,  between  of plants  i n the  therefore  kept  air.  the  Plant  same i n to  thetically  active  radiation  level,  0.4  (^E  cm  second  in  min  injury  leaf  area  an ambient  acute the  (Model  ),  (PAR)  air  in  per  chamber were  and ozone  the  days.  60)  (Fig.  2)  c h a m b e r s , at  plant  an I s c o  (LAN) for  Stomatal  per  level  was  0.5  SR)  meters  at  after  the  least  one day  resistance  (P ) g  as  plants  through  was measured on  bean l e a v e s w i t h a Lambda  chamber,  Air  flow  Air  was pumped f r o m o u t d o o r s , at  s y s t e m was  a relative  thermocouple  Mean a i r  1.2  of  primary  15 x 11 x 5 cm ( F i g . liters  filtered  humidity  chamber by means o f  controlled bubblers.  had b e e n  following  a s y s t e m c o n t a i n i n g one a t t a c h e d  the  percent  porometer.  sealed in a plexiglass  fumigation  plant  (Model  was a s s a y e d v i s u a l l y ,  necrotic  diffusion  psychrometry i n  and k e p t  treatments. Photosyn-  T r a n s p i r a t i o n was measured by d i f f e r e n t i a l  leaf  to  number  square centimeter  Air velocity . at  surface of primary  Li  numbers p e r  as measured w i t h  environment  treatment.  lower  found  (m s e c "*") .  Acute primary  was  -1  spectroradiometer. per  chambers  humidity  on a l t e r n a t e  microeinsteins - 2  minute  capacity  the  the  d e p e n d i n g on the  filtered  P o t s were w a t e r e d  was  Relative  largely  chamber.  in  used i n  per minute  through  of  temperature  (1 min  charcoal,  50% when e n t e r i n g  a series  3).  the  temperature i n the  chamber was  ^).  39  32  C , mean l e a f - 2 cm  min  (Model  8250)  ozone  was  30  C . PAR a t  the  leaf  was  -1  4.5^E  724)  temperature  . Ozone was g e n e r a t e d  ozone  with a Monitor  s o u r c e and m o n i t o r e d  Labs  w i t h a Mast  (Model  meter.  Grapevines  One-year-old (Vitis in  rooted  labruscana,  a mixture  of  Bailey)  1:1:1  June  at  the  15 t h e y  design of  et  al.  height  was  on the  g r o u n d a r o u n d the  single  20-year-old  (1973)  'Concord'  vine  system i n  capacity  weekly,  and e a c h p o t  fertilizer  charcoal-filtered  to  air  the  a chamber  trained  on A u g u s t  19.  air,,  early  to  May.  leaf  out  New Y o r k .  that  to  P o t s were  for  min,  placed a  the  P o t s were w a t e r e d  to  one ounce  of  W i t h two the  (28.4g)  treatments,  experiment  was  duplicate  Samples were r a n d o m i z e d  five  the  containing  once e a c h 65  done .  according  position.  Ozone was m o n i t o r e d  On  chamber  a c c o r d i n g to  b l o c k d e s i g n , w i t h two  t r e a t e d as b l o c k s .  chamber  except  of  received  pots  chambers b u i l t  meters).  center.  and ambient  a randomized  in  Fredonia,  4)  cultivars  12 cm c l a y  (2.7  perimeter  Kniffin  chambers  in  (Fig.  feet  Umbrella  50-50-50 N-P-K  grape  s h o o t and a l l o w e d  Laboratory  i n c r e a s e d to nine  to  in  were p l a c e d w i t h i n o p e n - t o p  Heagle  according  three  soil:peat:perlite,  a single  Vineyard  of  were p l a n t e d  (v/v)  They were r e d u c e d t o outside  cuttings  min,  Figure  5-  A c u t e ozone f u m i g a t i o n  chamber  41  in  each chamber,  Labs  (Model  8410E)  Over t h e overall air,  air  is  an i m p o r t a n t  to  not  and a  Monitor  were  as g r e a t to  0.04  ppm i n  chambers,  as i n their  of  ninth, the  and 0.01  ambient  ppm i n  filtration  growth  the  in  cabients,  effectiveness  in  the  open-top and  this  experiments  concentrations.  Six vines  of  each c u l t i v a r  chamber)  and d i v i d e d  and r o o t  portions.  (leaves  and s h o o t s ) Leaf  were h a r v e s t e d  on J u l y t w e l f t h ,  twelfth,  reweighed.  air  September  The e f f i c i e n c y  limitation  ozone  (three per  ambient  chambers.  chambers  w i t h low  the  1003AH)  monitor.  p e r i o d August f i r s t  ppm i n  filtered  is  ozone  a Dasibi(Model  mean ozone c o n c e n t r a t i o n s  0.03  field  u s i n g both  into  leaf  or  for  August n i n t h ,  (including  Those p o r t i o n s  from each  petiole),  were w e i g h e d ,  48 h ( t r u n k  a r e a was e s t i m a t e d  and  September  shoot,  dried  and r o o t s )  treatment  at  by c o m p a r i n g t h e  trunk,  overnight 70  C,  and  dry weight  2 three  leaf  entire  sections  three  canopy, with t o t a l  An a d d i t i o n a l fumigated chamber growth  of  (Fig.  5)  chamber.  relative  leaf  six vines  w i t h 0.75  cm  each chosen at  dry  per  ppm o z o n e ,  s i x h,  per in  treatment,  a clear  humidity  was  during  fumigation  was  25  C and  80%.  Ozone was g e n e r a t e d  by p a s s i n g f i l t e r e d  air  over  were  plastic  121: x 30 x 84 cm, p l a c e d w i t h i n a w a l k - i n Temperature  the  weight.  cultivar,  for  random f r o m  a  of  Table  1.  Ozone m o n i t o r i n g d a t a , A u g . 1 t o i n o p e n - t o p chamber e x p e r i m e n t  Treatment  Sept.  9,  1977  Overall  mean  Maximum  # Readings g r e a t e r t h a n .08 ppm  ML  DAS  ML  ML  DAS  7  Z  DAS  Ambient  air  chamber  (1)  .03  .03  .12  .10  19  7  Ambient  air  chamber  (2)  .03  .03  .13  .10  17  5  1  0  6  4  53  41  Charcoal f i l t e r e d chamber  (1)  Charcoal f i l t e r e d chamber  (2)  Ambient  •  air  .01  .09  .06  .01  .01  .11  .10  .04  .04  .13  .13  .01  •  samples for the two monitors were removed simultaneously monitors were calibrated every two weeks against a Monitor Labs ozone source x  one  reading  = maximum d u r i n g  ^Monitor  Labs  (Model  Dasibi  (Model  1003  z  8410 AH)  E)  ozone  5 minute ozone  period,  once p e r  65  minutes  monitor  monitor 4^  43  ultraviolet  bulb,  and m o n i t o r e d w i t h a Mast  (Model  724)  - 2 ozone m e t e r .  PAR i n  the  chamber was  measured w i t h a Lambda (Model level,  and a i r  Stomatal  flow  through  resistance  (R )  Li  the  9.8  185)  chamber was  introduction  introduction porometer.  of  of  Symptoms o f  following  leaf,  chlorophyll rinsing  day on two  in  percent  leaf  acetone  for  al.,  discs  the m i d r i b ,  15-20  min i n  in  ambient  to  6.6 /A. E cm  attached  to  the  min  underside of  Beckman (Model  215A)  Eastern  1100AP)  September h a r v e s t ,  infrared  the  PAR. the  correlations  parameters  of  c o u l d be  diffusion  similar  to  those  were a s s a y e d  clearing  same  of  70% e t h a n o l  in  the and  min.  dew p o i n t  the  was  and a  assessed.  stomatal  provide  cm c u v e t t e  the  both  so t h a t  behavior,  a  General  For  same v i n e s were u s e d f o r  injury,  to  c o n n e c t e d to  hygrometer.  assays  from  greenhouse,  floodlamps,  gas a n a l y z e r  growth measurements, and f u m i g a t i o n vine  prior  65)  A 5 x 3 x 1/2  leaf  .  surface  from t h i s  15-20  air,  1  and a s s a y e d  after  an a d d i t i o n a l  1 min  the  Li  1972)  taken  l i g h t provided with - 2 -1  3.6  (Model  et  plant  r a t e was a l s o m e a s u r e d , on v i n e s  September h a r v e s t ,  with supplemental  for  (Model  ozone i n j u r y  area n e c r o t i c  by b o i l i n g  Photosynthetic  from  (Shaulis  one f r o m e a c h s i d e o f  visually, for  the  acute  at  lower  and two h a f t e r  o z o n e , w i t h a Lambda  described previously the  ozone,  as.  immediately  ;  the  350  was m e a s u r e d on t h e  s  min  radiometer,  o f ."leaf. f ^ J - f r ^ ^ a s a l ) ) on each v i n e , to  E cm  -1  the  vine-to-  and  growth  44  Results  Susceptibility To d e t e r m i n e of  the  ozone on p l a n t  effect  response to  b e a n s e e d l i n g s and m i n t were  e x p o s e d to  days,  prior  six h  (bean)  acute  doses  injury,  in  filtered of  to  0.3  the p r i m a r y  cuttings  ppm f o r  18 h  plants  numerical  leaves  the  t h a t was n e c r o t i c  pretreated  pretreated  i n bean p l a n t s  f r o m an a c u t e  In  acute  pretreated of  (LAN),  the  with  area  after  acute  w i t h a s u b - a c u t e ozone e x p o -  injury for  after  the  the  same a c u t e  same p e r i o d i n  was r e d u c e d f r o m 331  with f i l t e r e d  air  ex-  filtered  to  14% LAN i n  dose by s u b - a c u t e p r e t r e a t m e n t  some f o r m o f  acclimation.  d r o u g h t , - and o t h e r  the  the  plants  indicated  T h i s may  the  the  tentatively  hardening of  plants  plant stresses.'  t h e more o z o n e - t o l e r a n t  ozone p r e t r e a t m e n t  LAN i n  T h i s p r o t e c t i o n o f bean  be c a l l e d h a r d e n i n g , by a n a l o g y to cold,  of  2).  ozone-pretreated plants.  to  ppm f o r  respective  ratings  percentage  injury,  seven  0.15  These  Visible  dose,  for  dose o f  (mint).  doses  greenhouse  day,  in plants  pretreated  presence of  the  respective species,  p o s u r e on p l a n t s  Injury  an a c u t e  equivalent  in plants  (Table  raised in  ppm o z o n e , s i x h p e r  s u r e was compared t o v i s i b l e  air  sub-acute pretreatment  a subsequent acute  an e x p o s u r e t o  l e d to  air.  treatment  0.02  or  the  of  had l i t t l e  species,  effect  mint,  the  same  on s u s c e p t i b i l i t y  to  45  Table  2.  Acute i n j u r y s u s c e p t i b i l i t y of g r e e n h o u s e - r a i s e d b e a n and m i n t after sub-acute pretreatment.  . . W Acute i n j u r y % l e a f area n e c r o t i c  Pretreatment  Filtered 0.02  Bean  air  .  ppm ozone  +  S E , n = 24  Mint  3.2  32 *  14 ± 2.5  The r e s u l t s d e s c r i b e d i n have p r e v i o u s l y a p p e a r e d R u n e c k l e s , V . C . , and 52: 2607- 2610 R u n e c k l e s , V . C . , and 55:193-197 W  33 *  Y  -  table  X  1.  3 9 - 2  this in: P.M.  and i n F i g u r e s 6 t o  Rosen.  1974.  Can.J.  Bot.  P.M.  Rosen.  1977.  Can.J.  Bot.  10  38  v  Acute dose: Y Acute dose:  0.3  ppm p e r  6 h per day,  3 days 1  0.15  ppm f o r  6 h  values of n refer to numbers of plants values for a single plant represent the mean of two primary leaves i n bean within experiments, single plants are treated as r e p l i c a t e s experiments were r e p l i c a t e d 2-3 times  46  acute  injury,  species,  therefore,  be d i r e c t l y the  increasing the  related  more s e n s i t i v e  toward  slightly.  tendency  Comparing the  toward  susceptibility  species,  bean,  hardening  to  acute  hardening  effect  the  range  of  conditions  and t e n  days  to  i.e.,  tendency  days.  Within  this  of pretreatment,  i n c r e a s i n g the  range  beginning  eight  concentration  appeared  to  a threshold  above  that  two  ages,  6).  in  i n age  and  The e f f e c t examined  seven-day  Increasing  the  seven,  consistently  susceptibility  Response to  five,  to  the  a protective  by pretreatments pretreatment  acute  pretreatment effect  dosage and a p r e d i s p o s i t i o n  of  injury thus  occurring  occurring  dosage.  To l o o k more pretreatment convenient  (Fig.  sowing.  c o n s i s t of both  below  was  dose was a l s o  i n c r e a s e d the 6).  >,  variation  concentration  days a f t e r  shown i n F i g .  of  sensitivity  pretreatment  increasing pretreatment  of  this  from s o w i n g , and t h r e e . d u r a t i o n s  d i m i n i s h e d by ozone p r e t r e a t m e n t  rather  injury,  under which  seedlings  o f p r e t r e a t m e n t w i t h low ozone were u s e d '  (as  appears  shows a g r e a t e r  occurred i n beans,  and f o u r t e e n  length  two  hardening.  To i n v e s t i g a t e  eight  to  it  dosage on a c u t e  to  than  pretreatment  extensively  vary  the  the  at  effect  susceptibility,  duration  concentration.  concentrations  the  of  the  more  pretreatment  dose  0.02  it  increasing was  T h i s was  of both  of  done w i t h ppm and 0.05  ppm  47  1  0 Figure  0.02 0.04 Pretreatment 6.  \  1  0.06 0.08 Ozone C o n c e n t r a t i o n  1  0.10 (ppm)  A c u t e ozone i n j u r y t o b e a n p l a n t s p r e t r e a t e d w i t h v a r i o u s s u b - a c u t e d o s e s . Numbers on c u r v e r e f e r t o age (days f r o m s o w i n g ) a t s t a r t o f p r e t r e a t m e n t ; • , 7 d a y s , a c u t e d o s e 0.15 ppm, 6 h ; •., 7 d a y s , a c u t e d o s e , 0.4 ppm, 6h^»5 d a y s , -A-7. days • 10 d a y s , a c u t e d o s e , 0.4 ppm f o r 2x6h; +_ SE of r e p r e s e n t a t i v e t r e a t m e n t s , n=6-10. See n o t e to T a b l e  2.  ,48-.  ozone of  (Fig.  0.02  7).  Using a constant pretreatment  ppm, and v a r y i n g  f r o m one to n i n e pretreatment (Fig.  7).  were  for  pretreatment  1.08-  at  0.48  with  0.06  have  this  at  a constant In  exposure to  to  0.02  six  to  Hence,  it  the  dose o f  6),  ppm-h.  also  concentration of  three  the  days  ppm-h.  0.05  range  (Fig.  the  Significant total  dosages of  the  not the  required  determine  p r e d i s p o s i t i o n was a s t r i c t  .  ultimately  senescence of  p o s s i b l e to  of  7),  determine whether,  p e r i o d of  whether  in  2.52  r e s p o n s e was  o f p r e d i s p o s i t i o n , were  was n o t  dosage, i . e . ,  from  ppm, s u s c e p t i b i l i t y w o u l d  time  and  for predisposition;  d a y s , at  system because of  leaves within  cumulative  0.90  day)  (Fig.  experiment,  f r o m one to  Attempts  a stage  possible with this  that  of  thus  information  of  i n d o s a g e from 0.30  p r e c i s e l y whether  The r a n g e  ppm; 6 h p e r  linearity  p r o t e c t i o n was  experiment.  relatively  p r o t e c t i o n was  0.02  of  protection  days.  a total  one t o n i n e d a y s .  i n c r e a s e d to  primary  five  or  ppm-h and g r e a t e r .  daily  remained  for  days  onset of  ppm was r e q u i r e d  predisposition occurred after  in  four  day,  t e s t e d by p r e t r e a t m e n t  1.80  pretreatment  increasing concentrations  The a p p r o x i m a t e  a range  effect  a further  seven days, s i x h per  effective  the  T h i s may be compared to  which approximately  ppm f o r  for  (i.e..', 4 days o f  ppm-h.  of  appeared that  required  least  duration  dosage e f f e c t i v e  pretreatments  for  it  This protective  constant  between  days,  the  concentration  more  function  p r e d i s p o s i t i o n would  of have  ,  ,  I  I  I  Days from Sowing Figure 7 .  E f f e c t of i n c r e a s i n g pretreatment dose on acute ozone s u s c e p t i b i l i t y of bean. D a i l y pretreatments, 6 h per day, with e i t h e r 0 . 0 2 ppm (») or 0 . 0 5 ppm ( H ) ozone, a f t e r t r a n s f e r from f i l t e r e d a i r at day 8 ; + SE of r e p r e s e n t a t i v e treatments, n = 6 . See. note to Table 2 .  50  occurred after ppm.  approximately  The i n t e r r e l a t i o n s h i p  treatments  at  lower  ten  days o f  between  0.02  d o s a g e s , however,  exposure to  0.02  ppm and 0.05  ppm  suggested that  this  m i g h t be s o . The r a n g e o f about  0.30  to  1.00  predisposition extent to  effective  protection  p p m - h , f o l l o w e d by a t r a n s i t i o n  at  about  1.00  to  1.80  ppm-h.  2.7  ppm-h  ( n i n e d a y s , 0.05  ppm).  a p p e a r e d to be s i m p l y t h e p r o d u c t o f w i t h no extreme  (0.0 2 ppm t o While  non-linearity  0.0 5 ppm, one t o  these  nine  ranges p r o v i d e  the  ranges  prior  to  an a c u t e  on a c u t e  exposure during  field  effects  of  s u s c e p t i b i l i t y and on p l a n t  pretreatment  exposure.  Effects  of  'Ives' exposures the  field,  tested  of  the  e p i s o d e s , study  of  sub-acute exposure  growth  required  a longer  season-long sub-acute three  grape. is  in  t h e most s e n s i t i v e  the  in  laboratory,  areas  the most t o l e r a n t , susceptibility pretreatment  dosage  immediately  e x p o s u r e on a c u t e s u s c e p t i b i l i t y were examined i n cultivars  up  and  a good a s s e s s m e n t o f  s u b - a c u t e e x p o s u r e s w h i c h may o c c u r  between t h e  least  the  days).  of  interactions  at  Effective  kinds  the  to  concentration in  from  Above t h a t ,  of p r e d i s p o s i t i o n increased with dose,  about  time,  a p p e a r e d t o be  of and  (Kender  for  one to  grape c u l t i v a r  acute  and shows t h e most i n j u r y  h i g h ambient  ozone.  'Concord'  of  is  and C a r p e n t e r , three  to  'Delaware'  in is  intermediate 1974),  After  months w i t h e i t h e r  filtered  air  51  o r ambient ozone,  air  (representing  respectively--see  an a c u t e  dose o f  tolerant  of  the  0.75  averages  Table  1),  cultivars,  0.01  or  0.03  s i x h.  The most  'Delaware',  was  w h i c h t h e r e • was a s t a t i s t i c - a l l y - s i g n i f i c a n t  effect  of  of pretreatment, p r e d i s p o s e d to with f i l t e r e d This mint,  vines  acute air  finding  In  that  pretreated  injury  (Table  case,  as compared t o  s u p p o r t e d the  to p r e d i s p o s i t i o n .  be above  hardening,  encountered  the  in  the  from T a b l e  data  statistical  phenomenon o f 3,  significance,  an e a r l y  a late  season tendency  effect  o f p r e t r e a t m e n t was  change i n a c u t e  tolerant  in  protection  is  likely  susceptibility  with  in  level  of  and  was f o l l o w e d Although  by this  different time,  with changing  results  area,  Trends the  to  will  'Concord'  predisposition.  s u p e r i m p o s e d on a  the  have  pretreat-  plants  below  and  an  of  concern.  suggested that  toward  to  case,  The range  although  susceptibility  dosage h e r e was s i m i l a r  this  bean  so t h a t w i t h i n t h i s  in  season p e r i o d of  changing acute  in  greatest  however,  'Ives'  of  pretreated  plants  s e a s o n - l o n g exposures  phenomenon o f p r e d i s p o s i t i o n be the  of  or,  region of p r o t e c t i o n ,  probably  were  c o m p a r i s o n between  i n c r e a s e d tendency  curve  vines  months  3).  to  the  air  w h i c h s u g g e s t e d t h a t more o z o n e - t o l e r a n t  doses  only  three  w i t h ambient  a reduced tendency  ment  after  to ozone  the  one / i i i  pretreatment.  ppm  v i n e s were e x p o s e d  ppm ozone f o r  three  of  the  pattern  pretreatment  obtained with  bean.  52  Table  5.  Acute i n j u r y s u s c e p t i b i l i t y of potted grapevines grown i n a m b i e n t a i r (AA) o r c h a r c o a l - f i l t e r e d a i r *(CF) . V INJURY  Date  Cultivar  Treatment  JULY  AUGUST  SEPTEMBER  Ives  Concord  CF  20.0  8.1  0.0  AA  20.0  4.8  0.0  CF  39. 5  39 . 8  AA  2 2.0  21.3  CF  1.3  1.1  1.0  AA  2.5  1. 8  3.2  S i g n i f i c a n c e of treatment e f f e c t  Leaf  area  necrotic  * = 51 l e v e l Two way a n a l y s i s  of  after  6 h,  variance,  0.75  ppm ozone  treatment x  : time  Delaware  53  The i n t e r p r e t a t i o n r a i s e d bean p l a n t s ,  of  experiments  and c o m p a r i s o n w i t h  with greenhousefield  exposures,  depends on a s s u m p t i o n s a b o u t n o r m a l b a c k g r o u n d l e v e l s ozone.  Use o f  protective  effect  acclimation  to  experiments. the  t h e word " h a r d e n i n g " to of  sub-acute pretreatment  low ozone o c c u r r e d o v e r If  describe  the  the  assumes t h a t course of  a low b a c k g r o u n d c o n c e n t r a t i o n o f  ozone  time s c a l e , the  difference  in  s u s c e p t i b i l i t y w h i c h has b e e n a s c r i b e d t o h a r d e n i n g be more a c c u r a t e l y d e s c r i b e d as d e h a r d e n i n g , i . e . , harmful  effect  pretreatment case,  of  of  filtered  w i t h normal  c o u r s e , the  developed over the would e x i s t it  would e x i s t  air  pretreatment  in  to  a  as compared t o  in  the  hardening, while  as a " p r e f e r e n c e "  In  either  ozone w o u l d . h a v e  same t i m e s c a l e , b u t for  acute might  low ozone c o n c e n t r a t i o n s .  adaptation  as a c a p a c i t y  these  a n o r m , and radaptation^"- has  atmosphere r e p r e s e n t s  occurred over a longer  of  for  growth  in  one c a s e in  the  it  other  low ozone  concentrations. To t e s t in  either  these a l t e r n a t i v e s ,  continuous f i l t e r e d  0.02  ppm ozone was added f o r  type  of p l a n t s  before of the  acute  were t h e n  fumigation.  e x p o s u r e to  0.02  air  or  transferred If  filtered  s i x h per to  day. the  air  to  Some o f  which each  alternate  h a r d e n i n g o c c u r r e d as a  ppm w e - w o u l d  s u s c e p t i b i l i t y of  beans were grown f r o m s e e d  expect  those p l a n t s  to  started  regime result  see a d e c r e a s e in  filtered  air  in  54  and t h e n  switched  to  daily  those p l a n t s  remaining  filtered  air  itself  increase  in  in  exposures  daily  filtered  the  air,  low ozone  susceptibility to  (Fig.  air  persisted  solid  the  we w o u l d of  expect  to  If  to  those p l a n t s  those p l a n t s  effect  air  time the  lines),  greater in  through  nificantly  in  throughout.  ppm ozone and t h e n  with continuous  8 A,C,  decrease  air  as compared  see  an  started switched  exposed to  to  daily  throughout.  filtered  which  0.02  as compared t o  significantly in  exposures  filtered  was h a r m f u l  Comparing f i r s t filtered  in  ozone  early  day 17 b u t  susceptibility  in  the  The t r a n s f e r continuous  of  (Fig.  8C)  the  pattern of  to was  air  d i d not  to  of  growth  injury. to  early  from d a i l y  0.02  (Fig.  21,  which  during  became  that  sig-  early observed  for  growth. ppm ozone 8A)  i n any s i g n i f i c a n t  increasing susceptibility  13),  This  allowing  during  grown  (day  regime  comparable  on day e i g h t  result  but  the p l a n t s  either  6,7),  in  pretreatments  a small in  acute  (Fig.  plants  treatment  d i s a p p e a r e d by day  environment  filtered  ten  stages  subjected  g r e e n h o u s e - r a i s e d beans  differences  ozone  t h e r e was  more s u s c e p t i b l e  in  daily  continuous  susceptibility  the  plants  of  to  o r on day change  with time.  - .  in  55  Figure  8.  A c u t e ozone s u s c e p t i b i l i t y o f beans a f t e r g r o w t h i n continuous f i l t e r e d a i r or various patterns of d a i l y e x p o s u r e t o 0.02 ppm o z o n e . S u s c e p t i b i l i t y c a l c u l a t e d as a c u t e i n j u r y p e r t o t a l a c u t e d o s e (about 3 p p m - h ) . V e r t i c a l b a r s a r e s t a n d a r d e r r o r s ( n = 4 ) . Arrows i n d i c a t e day on w h i c h t r a n s f e r between p r e t r e a t m e n t regimes' o c c u r r e d . P r e t r e a t m e n t s : o , c o n t i h o u s f i l t e r e d a i r ; 4*', d a i l y 0.02 ppm o z o n e ; . © ' , . . t r a n s f e r r e d f r o m d a i l y ozone t o c o n t i n u o u s f i l t e r e ' d a i r ; © , t r a n s f e r r e d from c o n t i n u o u s f i l t e r e d a i r to d a i l y o z o n e . A , B , C , and D r e f e r , t o s e p a r a t e e x p e r i m e n t s . See n o t e t o T a b l e 2.  57  Hence i t between  is  apparent  filtered  raised plants effect  of  In  air  that  the p r e v i o u s l y noted  and ozone p r e t r e a t m e n t  c a n n o t be e x p l a i n e d i n  filtered  contrast,  of of  the  daily  reverse  i n s u s c e p t i b i l i t y , w h i c h a p p e a r e d to  (Fig.  8 A,  (Fig.  8 B).  those  transferred  eight  d a y s , at  three, C, D ) , After  of plants  four, but  or  this  early  plants  s u b j e c t e d to of  and t h o s e t r a n s f e r r e d  filtered  between  air  8 A, C).  rise,  the  the  any o t h e r  the  to  in  grown i n  two  the  in plants  appears  that  low o z o n e .  the  case of p l a n t s  than  air the  throughout same as  grown  day 13  there  21 days  the  in (Fig.  was a  i n the pattern'of increasing  initial  transferred  of  next  lower  filtered  s u s c e p t i b i l i t y with age of plants from sowing.  susceptibility  is  days  susceptibility  low o z o n e , a t  the  least  pretreatment  s u s c e p t i b i l i t y of plants  appeared only a f t e r  effect  susceptibility  low o z o n e , was a b o u t  As a c o n s e q u e n c e i t  at  pretreatment.  difference  and t h o s e grown i n  In  ozone  appeared a f t e r  rapid  require  Thus t h e  days o f  d e c r e a s e caused by low ozone pretreatment  however,  harmful  in a  remained constant over  s o w i n g , between p l a n t s  difference  itself.  five  had n o t  resulted  a l e v e l w h i c h was s i g n i f i c a n t l y  The m a g n i t u d e after  ppm ozone)  exposures to m a n i f e s t  after  the  (from c o n t i n u o u s  increase  that  0.02  transfer  air  clear  greenhouse  air.  filtered  two d a i l y  to  terms  differences  This decrease, increase  from f i l t e r e d  in air  r a i s e d from seed i n  to low  58  ozone,  the  latter  increase  the  trend  effect  d i s a p p e a r e d by  in susceptibility  toward  The e x p e r i m e n t s revealed  demonstrated  with f i l t e r e d  a stage  the  than  stage  air in  or  the  0.02  a  noted  ppm ozone  pretreatment  o f p r e d i s p o s i t i o n , when  major  greenhouse-raised plants rather  to  of  d o s a g e , as  with greenhouse-raised p l a n t s .  that  This  plants.  an e a r l y  on s u s c e p t i b i l i t y , experiments  8A,C).  seems to be a n a l o g o u s  increasing pretreatment  with greenhouse-raised  to  (Fig-  an i n c r e a s e d p r e d i s p o s i n g e f f e c t  pretreatment with  s e e d thus  21 days  was  effect  in  those  describable  effect  compared  They  also  experiments  as a  from  with  hardening  dehardening.  Stomata In  experiments  possibility  that  observed e f f e c t susceptibility plants both  during  w i t h g r e e n h o u s e - r a i s e d bean s e e d l i n g s ,  stomatal of  was the  behavior  was  involved  sub-acute pretreatment t e s t e d by m e a s u r i n g ozone-free  sub-acute pretreatment  part  of  and t h e  on  the  the  R  in  the  the  acute g  daily  of  those  cycle,  subsequent  during  acute  treatment. It  appeared  pretreatment explanation (K )  of  that  stomatal  exposure might of  the  effect  closure  be at  i n d u c e d by  least  on i n j u r y .  g r e e n h o u s e - r a i s e d bean p l a n t s  a  the  partial  The s t o m a t a l pretreated  conductance  with  three  daily  doses  (six  h)  compared t o p l a n t s After  a further two  these p l a n t s  after  filtered  air.  would appear the  leaf  the  to  least  part  of  acute  and t h e  determinant Since ozone-free  of  c l o s u r e are  evident  apparent  relative  stage  effect  stomatal  further  pretreatment-  periods, neither  to  in  Figure  treatments  The s t o m a t a l  on t h e  acute  this  two  9.  after  closure  in  the p h y s i c a l that  treatments  exposure,  aperture  effects  was n o t  was  indicating a  primary  of  the  were m e a s u r e d d u r i n g types  irreversible  response,  there  effect  ozone w h i c h o c c u r s  of  into  injury.  these stomatal  addition  ozone  c l o s u r e o b s e r v e d on  in both  o b s e r v e d h e r e was r e v e r s i b l e by r e m o v a l In  in  and m e s o p h y l l i c t i s s u e s i n d u c e d by  by an a d d i t i o n a l  of  in  effect  e x p o s u r e may have b e e n due t o  exposure,  this  were  with  e x p o s u r e as a r e s u l t  dose on day f i v e .  epidermal  at  pretreated  of  closure is  damage t o  that  acute  53% l e s s  protective  9).  injury  reduced entry  stomatal  acute  affected  this  plants  Visible  the p r e t r e a t m e n t - i n d u c e d  the  not  e x p o s u r e s was in plants  of  further  to  acute  (Fig.  closure.  day f o u r ,  response  of  to have b e e n due to  Two t y p e s  first  ozone.  air  the  doses  than  d u r i n g the  addition  with f i l t e r e d  plants  At  induced stomatal  In  ppm ozone was r e d u c e d 35% as  days o f p r e t r e a t m e n t ,  acute  ozone-pretreated  0.02  pretreated  two  s u b j e c t e d to  of  of of  stomatal the  form o f  may a l s o be a component o f  closure  ozone. stomatal  the  o n l y d u r i n g the  the  stomatal  presence of  ozone  6-0  4  5  6  Days A f t e r T r a n s f e r f r o m Figure  9-  7 Filtered Air  S t o m a t a l c o n d u c t a n c e o f beans d u r i n g s u b a c u t e p r e t r e a t m e n t and s u b s e q u e n t acute treatment w i t h ozone. F o u r t e e n - d a y - o l d seedl i n g s t r a n s f e r r e d to continuous f i l t e r e d a i r (O) o r d a i l y 6 h e x p o s u r e t o 0.02 ppm ozone (») f o r 5 days p r i o r t o a c u t e d o s e s (*) o f 0.40 ppm, ± SE, n=6. S t o m a t a l measurements made 1.5 h b e f o r e ozone e x p o s u r e and 1.5 h a f t e r b e g i n n i n g o f l i g h t p e r i o d . See n o t e t o T a b l e 2.  61  in  the  that  atmosphere.  s u b - a c u t e p r e t r e a t m e n t may a f f e c t  by a f f e c t i n g that  S p e c i f i c a l l y , there  stomatal  response to  d u r i n g the  To i n v e s t i g a t e  this  measured d u r i n g a c u t e filtered  air  f o l l o w e d by 0.02  schedule  described in  Figure  f u m i g a t i o n was o b s e r v e d a t response, days)  susceptibility  presence of  possibility, for  possibility  ozone i n a manner  ozone-free  fumigation  the  acute  acute  c a n o n l y be m e a s u r e d d u r i n g t h e  ozone dose and n o t  is  the  acute  period.  transpiration plants  was  pretreated  ppm ozone a c c o r d i n g to 8 A.  Stomatal  two s t a g e s  in  with  the  r e s p o n s e to  the  acute  susceptibility  the  early  stage of  increased s u s c e p t i b i l i t y  (14  and the  later  stage of  decreased s u s c e p t i b i l i t y  (21  days). At  14 d a y s , when the  p l a n t s was g r e a t e r filtered  air,  response  to  than  that  acute  in  pretreated  stomata o f the  to  with close  ozone e x p o s u r e w h i c h may e x p l a i n (Fig.  transpiration  treatments p r i o r  to  plants  immediately  whereas  transpiration  rates  pretreated  upon the  increase  reduced s e n s i t i v i t y  10A)-.  of  in for  the  acute  their  two  ozone  with f i l t e r e d  ozone-pretreated  two h b e f o r e  o f h i g h ozone c o n c e n t r a t i o n s ,  the  i n t r o d u c t i o n of  stomata to  in  A l t h o u g h t h e r e was no  between  the b e g i n n i n g o f  closure  c o n t i n u e d to  of plants  ozone-pretreated  s t o m a t a had a d e c r e a s e d a b i l i t y  increased s u s c e p t i b i l i t y difference  s u s c e p t i b i l i t y of  fumigation,  air  0.40  began ppm o z o n e ,  plants  c l o s u r e began.  closure in  the  in ozone-pretreated  This  presence plants,  62  Figure  10. .  T r a n s p i r a t i o n r a t e s o f a t t a c h e d p r i m a r y bean l e a v e s d u r i n g a c u t e ozone e x p o s u r e , a f t e r p r e t r e a t m e n t w i t h e i t h e r f i l t e r e d a i r o r 0 . 0 2 ppm o z o n e . A , 14 days f r o m s o w i n g ; B , 21 days from s o w i n g . P r e t r e a t m e n t s :. © , c o n t i n u o u s f i l t e r e d air-; © , t r a n s f e r r e d from c o n t i n u o u s f i l t e r e d a i r t o d a i l y 0.0 2 ppm ozone .(6 h p e r day) 7 days f r o m s o w i n g . Ozone ( 0 . 4 0 ppm) i n t r o d u c e d at a r r o w . Res u l t s shown h e r e a r e f r o m a r e p r e s e n t a t i v e r u n , : t r e a t m e n t s were r e p l i c a t e d 2-4 t i m e s . See n o t e t o T a b l e 2. J  63  o  1100  1200  1300  Hour of Day  1400  1500  1600  64  created wider  a period  and t h e  atmosphere  concentrations into  the  d u r i n g which  leaf  of at  injury At  ration  t i m e c o u l d have  this  21 d a y s , in  plants, of  at  acute  thus in  effect  of  plants air.  decrease  affected  r e s p o n s e to  stage  of  in  then  that  r e s p o n s e to  initial  14 the  plants  injury  may  behavior,  aperture,  caused  t h a n by  on s t o m a t a l  the  response for  to the  days. component o f  acute  exposure  low ozone p r e t r e a t m e n t  of  acute  rather  ozone c o n c e n t r a t i o n s  effect  to  were  difference  s u c h as was r e s p o n s i b l e at  rates  t h e y were i n  by s t o m a t a l  increased s u s c e p t i b i l i t y .  protective  concentrations  treatment  pretreatment  low ozone p r e t r e a t m e n t  presence of high the  than  The  explained  increased s u s c e p t i b i l i t y  which  sensitivity  transpiration  level  appeared  reduced  initial  by the low  ozone-pretreated  the  h i g h ozone c o n c e n t r a t i o n s  It  the  decreased s u s c e p t i b i l i t y  case,  by l o n g - t e r m  of  in  ozone  a l s o be p a r t i a l l y  this  to  transpi-  to h i g h  with f i l t e r e d in  fumigation,  in  stomata  in ozone-pretreated  resulting  the  plants  any d e c r e a s e  a continuation  t^'ig. 10B). At 21 daysj  pretreated  ozone  accounted for  ozone-pretreated  absence o f  r e s p o n s e to  ozone-pretreated  lower  of  of  stage.  the  indicated  open toxic  The i n c r e a s e d e n t r y  increased s u s c e p t i b i l i t y acute  s t o m a t a were  contained p o t e n t i a l l y  ozone. that  the  In  was  stomatal  behavior  only  during  also  involved  during  the  contrast,  low ozone p r e t r e a t m e n t was  the in  early the  later  associated  65  w i t h an i r r e v e r s i b l e they  acute  Further  of  existence response ozone,  investigation  changes i n  filtered  acute  for  air the  g  tested.  of  trends not at  equivalent  an e n t i r e  on s t o m a t a l  R in s  filtered  air  to for  to  an e f f e c t 'Delaware'  time,  response to  injury  on p o l l u t a n t after  three  initial  acute  R  g  treatment or  the  change cultivars  concentrations with  The p r e d i s p o s i t i o n  entry,  appear  although  to the  be data  months o f p r e t r e a t m e n t that  'Delaware'  type.  vines  and a l e s s e r d e g r e e  fumigation.  the  experiments  d i d not  a p o s s i b l e mechanism o f ozone-pretreated  As  h a d no m e a s u r a b l e  in.grape.  acute  filtered  ppm o z o n e .  i n any o f  those used i n  behavior  periodically  &  fumigation,  to  of  the  was m e a s u r e d i n  growing s e a s o n ,  vines  have b o t h a l o w e r in  chambers  sub-acute pretreatment  contradict this  pretreatment  were no s i g n i f i c a n t  initial  stomatal  instance  were removed f r o m  f u m i g a t i o n w i t h 0.75  there  that  the  growth.  E x p o s u r e to  'Delaware'  related  4,  of  levels  in  acute  for  effect  air  low  r e s p o n s e to  approximately bean,  two h o f  on e i t h e r  in  experiments  determine  types  relationship  g r o w i n g s e a s o n and R  shown i n T a b l e  in R  their  or ambient  and a f t e r  effects  to  these  s u s c e p t i b i l i t y and  these  which  t h e s e p o s s i b i l i t i e s was  importance of  determine  of  exposure.  d u r i n g a s e a s o n - l o n g exposure to  and t o  through  as a r e s u l t  experiments w i t h g r a p e v i n e s ,  and r e l a t i v e  Vines  air  on s t o m a t a  showed ho r e s p o n s e t o  conducted i n  to  effect  did  Thus  tended of  to  closure  Tab1e  Date  S t o m a t a l b e h a v i o r o f p o t t e d g r a p e v i n e s grown i n a m b i e n t a i r (AA) o r c h a r c o a l - f i l t e r e d a i r (CF).  Treatment  JULY  AUGUST  SEPTEMBER  V  4.  V  Ives initial R  CF  12 . 5  AA  change in R s  Delaware initial change R in R  S  0 .8  4.1  0.4  7.7  3.5  7. 9  2.1  4.0  •0.1  9 .1  2.2  CF  2.1  1.3  AA  2.. 9  CF AA  resistance  (sec  cm  ,  3,4  0 .4  1.4  3.1  0 .2  7. 7  -0.3  5.1  1.7  5.1  3.9  5.8  -0.2  4.4  1.0  4 .2  3.4  D a t a show no s i g n i f i c a n t t r e a t m e n t v a r i a n c e , t r e a t m e n t x time  W Stomatal  Cultivar Concord initial cTTange R in R • W  -1  )  at  effects,  start  of  S% l e v e l ,  ozone  two way  analysis  of  fumigation ON  X  Change  in  stomatal  resistance  (s ec cm  -1  )  after  2 h of  0.75  ppm ozone  67  Growth The i n v o l v e m e n t stomatal  of  an i r r e v e r s i b l e  f u n c t i o n w i t h the p r o t e c t i v e  ozone p r e t r e a t m e n t ,  in bean,  dampening o f  effect  growth.  and s u s c e p t i b i l i t y r e s p o n s e s c o u l d r e s u l t  however,  stomatal, that  the  mechanism.  effect  of  It  rate  or that  it  Exposure  o f bean s e e d l i n g s to  sowing  (Pig-  found to  11).  inhibit  Transfer  eight, the  from 0.02  had no e f f e c t  importance  effect  of  of  low ozone a t  to  growth  in  a difference After at  s u b - a c u t e ozone  the  than  on stem h e i g h t first  eight  day e i g h t  filtered  air  filtered  by day 2 5 ,  days o f Transfer  on stem h e i g h t  was s i g n i f i c a n t l y  air  ppm  at  day  indicating for  the  frOm f i l t e r e d in  by day appear  to  from  filtered  air,  growth  a l s o h a d no e f f e c t  may have been b e g i n n i n g t o  the  0.02  t h o s e grown i n  ppm ozone t o  b e i n g s w i t c h e d from f i l t e r e d  day e i g h t ,  on  stem growth by 21 days  ozone on stem g r o w t h .  to  any e f f e c t  S e e d l i n g s grown f r o m s e e d i n  ozone were f o u n d t o be s h o r t e r air.  on  c o u l d be a c c o m p a n i e d by an i n c r e a s e d  growth.  was  growth  from a s i n g l e ,  sub-acute pretreatment  of plant  treatments  B o t h the  of  was a l s o p o s s i b l e ,  a c u t e s u s c e p t i b i l i t y was i n d e p e n d e n t o f growth,  sub-acute  s u g g e s t e d the p o s s i b i l i t y  an a c c o m p a n y i n g r e d u c t i o n i n p l a n t  primarily  of  0.02  air  relation 25, at  although  that  time.  ppm ozone  a c u t e s u s c e p t i b i l i t y o f bean s e e d l i n g s r e d u c e d by day  21,  so t h a t  even i f  this  68  Days from Sowing Figure 11.  Height o f bean p l a n t s grown i n f i l t ered a i r or 0 . 0 2 ppm ozone-. Treatments: O, f i l t e r e d a i r from seed; <• , switched from f i l t e r e d a i r to low ozone ( 0 . 0 2 ppm, 6 h per day) at day 8 ; • , low ozone from seed; o , switched from low ozone t o f i l t ered a i r at day 8 , ± SE of r e p r e s e n t a t i v e treatments, n=4.  69  switch point  d i d lead beyond  to a s i g n i f i c a n t  25 d a y s ,  t h e two r e s p o n s e s  s u s c e p t i b i l i t y ) would e x p e c t e d , hox^ever,  height  reduction  ( h e i g h t and  n o t be s y n c h r o n o u s .  T h i s would  t h e growth The  in  effect the  effect  o f a common s t o m a t a l mechanism  stem  on stem h e i g h t  first  during  on b e a n  eight  days  the f i r s t  growth,  o f exposure o f growth.  25 days  after  questions  effects  about  that  t o 0.02 ppm ozone  For  relationship  open-top  field  or  charcoal-filtered  between t h e growth and pretreatment.  chambers air.  on t h e e x p o s u r e o f growing  receiving  either  to  (Table  parallel  samples  grown  ambient a i r  V i n e s were removed f r o m t h e  f o r an a s s e s s m e n t  injury  season.  g r a p e v i n e s were  chambers p e r i o d i c a l l y a c u t e ozone  To answer  i t was n e c e s s a r y t o  f o r an e n t i r e  these experiments, p o t t e d  in  o f beans  sowing-were n o t a d e q u a t e f o r  o f low ozone  t o low ozone  after  D a t a on t h e growth  examine t h e d a t a f r o m e x p e r i m e n t s grapevines  o f these  b u t t h e d a t a showed no  an e v a l u a t i o n o f t h e r e l a t i o n s h i p susceptibility  linking  o f s u b - a c u t e t r e a t m e n t and a r e d u c t i o n  growth was n o t c o n t r a d i c t e d by t h e r e s u l t s  experiments  the l a g  r e s p o n s e c o u l d be e x p e c t e d t o be g r e a t e r .  possibility  a protective  be  i f b o t h o f t h e s e r e s p o n s e s were  m e d i a t e d by t h e same s t o m a t a l mechanism, s i n c e in  a t some  3).  of susceptibility  A t t h o s e same  were removed f o r a s s e s s m e n t  growth,  by measurement o f f r e s h w e i g h t  leaves,  stems,  t r u n k , and r o o t s .  intervals,  of vine  and d r y w e i g h t o f  7Q  In  vines of  i n ambient weight  air  the  'Ives'  than i n  filtered  and r o o t w e i g h t ,  weight,  were  treatments.  cultivar, air  fresh)  5).  In  vines of  the  'Concord'  and f r e s h  cultivar  only l e a f weights  significantly affected.  these  cultivar  i n ambient  In  greater Both top  a f f e c t e d a p p r o x i m a t e l y e q u a l l y by  in this  were  (Table  and b o t h d r y w e i g h t  growth was s i g n i f i c a n t l y g r e a t e r However,  g r o w t h was  air  also, (Table  (both  d r y and  'Delaware',  t h e r e were no s i g n i f i c a n t d i f f e r e n c e s i n v i n e  growth  between f i l t e r e d  (Table  air  The r a n k i n g o f effect  of  ambient  or ambient a i r  treatment  t h e s e c u l t i v a r s w i t h r e s p e c t to  air  versus f i l t e r e d  air  the  treatment  to  and C a r p e n t e r ,  1974).  The c u l t i v a r most s e n s i t i v e t o ozone  showed the  most ozone t o l e r a n t effect  on g r o w t h .  effect  of  this  greatest  cultivar, 'Delaware',  same t r e a t m e n t  sensitivity  appeared  related  'Ives',  injury  7).  t o be d i r e c t l y  injury,  their  6).  effects  'Delaware', however,  (Kender  on g r o w t h .  showed the  showed t h e  The  least  greatest  on a c u t e s u s c e p t i b i l i t y  (Table  3). Comparing c u l t i v a r s , the treatment,  therefore,  pretreatment e f f e c t sensitivity  positively w i t h the  of  low ozone  a p p e a r e d to be i n v e r s e l y r e l a t e d  ' on s u s c e p t i b i l i t y .  to ozone i n j u r y  low ozone t r e a t m e n t  growth e f f e c t  and t h e  on growth on the  c o r r e l a t e d , while both of  t o the  Baseline cultivar  stimulatory  effects  of  o t h e r hand were t h e s e were a s s o c i a t e d  absence of a tendency toward a p r e d i s p o s i n g  effect  Table  5.  Growth o f p o t t e d ' I v e s ' v i n e s i n ambient a i r or c h a r c o a l - f i l t e r e d a i r ( C F ) .  (AA)  leaf area F r e s h xveight  roots  1. 7  0 .8  5.1  7.0  324. 3  33. 6  2.3  1.1  5.3  7.9  15. 5  27.6.  1.8  0.8  7.3  7.1  14.6  38. 2  2. 7  1.8  5. 3  4.4  13.5  30 . 5  1.8  7.5  5.6  13.4  42.6  2.4  trunk  roots  JULY CF  6.9  4.1  11.3  26.6  AA  9.7  6.0  12.0  CF  6.4  3.2  AA  10 . 3  SEPT CF AA  AUG  Significance o f t r e a t m e n t * *ftft effect  L  wt  w  Treatment *  = 5%,  **  begun J u n e = 1%;  shoot  leaves  0 . 21  0 . 24  438.0  2. ,6-'0 . 24  0 .18  0.23  7.2  367.8  2.8  0. 26  0 . 26  0 . 29  6.8  8.9  .561.9  2.0  0.24  0 . 26  0 .27  1.3  7.1  8. 5  314.1  3.1  0.28  0 . 29  0 . 35  1.9  7.1  10.4  372.9  2 . 5 0 . 26  0.34  0 . 33  ft ft  ft  ftft  15  two way a n a l y s i s o f v a r i a n c e , t r e a t m e n t  x time,  n  =6  wt  J  0. 26  •3.0  w  v  dry w t / f r e s h  root  trunk  shoot  v  (cm )  weight  leaves" shoot  Leaves  Date  Dry  CR)  root top  Table  6.  Growth o f p o t t e d ' C o n c o r d ' v i n e s or c h a r c o a l - f i l t e r e d a i r (CF).  in  ambient  leaf area  Date  F r e s h w e i g h t (S) leaves shoot trunk roots  V  JULY CF  8.3  leaves  (cm ) Dry w e i g h t (g) shoot trunk roots  6.2  16.1  29.1  2.0  1.1  .7.5 8.0.  air  (AA)  root top L  wt  J  d r y w t / f r e s h wt root shoot leaves  7.8 4 2 6 . 3  2.5  0 .27  0 .19  0 . 24  7.7 465. 3  1.9  0 .23  0 .19  0 .25  AA  11. 3  7.1 :  17.5  33..5'  2.9  1.4  AUG , C F  11. 5  7.7  20 .4  38.9  3.3  1.9  10.0  8.5 634. 5  1.6  0 .22  0 .25  0. 29  AA  13.8  8.8  15. 6  60.0  4.1  2.3  7.7  10.1 760 . 8  1.7  0 . 20  0 . 26  0.29  SEPT CF  7.7  5.9  21. 3  4 3.9  2.9  '2.2  1-2.0  1 1 . 6 553. 5  2.3  0 .27  0 . 38  0 . 39  9.3  5.9  19 .6  47.0  3.5  11.2  12.2 555.9  2.2  0 . 26  0 . 36  0.37  AA  2 .2  Significancew of treatment * effect  vTreatment w.  5%;  begun J u n e  two way  15  analysis  of  variance,  treatment x time,  n-6  Table  7.  Growth o f p o t t e d ' D e l a w a r e ' v i n e s or c h a r c o a l - f i l t e r e d a i r ( C F ) .  i n ambient  air'(AA)  leaf area  Date v  F r e s h w e i g h t (g) leaves shoot trunk roots  leaves  root top  dry w t / - f r e s h wt root.shoot leaves  Dry w e i g h t (g) , shoot trunk roots  JULY CF  8. 2  4.0  17. 2  18.2  1.7  0,7  8.1  5.5  449 .4  2.4  0 . 30  0.17  0 . 21  AA  6. 8  3.1  17. 5  15.1  1.6  0.5  8.3  4.6  384 .0  2.3  0 . 29  0.17  0 .23  SEPT CF  5. 1  2.9  14. 8  24.4  1.6  0 .8  8.1  6.6  429 .0  2.8  0 . 27  0 . 29  0 .31  AA  6. 8  3.7  18. 5  30.4  2.1  1.0  10.0  7.8  537 . 6  2.6  0 . 26  0 . 29  0 . 30  Significance of treatment effect  begun June  _ .  v  Treatment  w  T w o way a n a l y s i s o f v a r i a n c e , t r e a t m e n t  _ -  a  n  NS -  15 x t i m e , n=6  -  -  -  74  of  low ozone  treatment.  However, baseline of  it  was  found t h a t  sensitivity  to  ozone  low ozone t r e a t m e n t ) ,  ment  on g r o w t h ,  on a c u t e  were  effect  effect  of  between  were  s u b j e c t e d to  than  in parallel  in  that  at  the  cultivars.  the  to  (smaller acute  8).  cultivar time  of  pollutant  the  various  'Delaware'  between  acute  e n t r y was o f  injury  (Table  and i n j u r y  the 9).  were  corre-  the  this  latter  growing season  analyses s e r i a l l y ,  v i n e s was  rather  positively  of  leaves  injury  and  correlation  and i n i t i a l  were more s u s c e p t i b l e  that  the  R  g  Vines with a higher  role  of  stomata  secondary importance  • there  any o f  of  to  an  R  g  to in indirect  i n c r e a s e d t o p growth and increased--  susceptibility- . .  between  treatment  b a s e d on v i n e - t o -  To t e s t  end o f  fumigation.  indicating  'Ives',  acute  aperture)  a s s o c i a t i o n between  In  treat-  T h e r e was a l s o a p o s i t i v e  stomatal  injury,  low ozone  samples.  injury  (Table  effect  cultivar-to-cultivar  c o r r e l a t e d w i t h f r e s h and d r y w e i g h t s shoots  the  low ozone  t h e s e same q u a n t i t i e s  vines h a r v e s t e d at  Acute  of  between  of  not n e c e s s a r i l y i n d i c a t i v e  vine v a r i a t i o n within point,  (regardless  s u s c e p t i b i l i t y , b a s e d on  variation, lations  and the  the  correlations  were  ' no s i g n i f i c a n t  growth p a r a m e t e r s  m e a s u r e d and  C o r r e l a t i o n s between  a l s o not  correlations  statistically  stomatal  acute variables  significant,  but  Table  8.  "Delaware': simple c o r r e l a t i o n s of growth, i n j u r y , and s t o m a t a l b e h a v i o r , S e p t e m b e r .  Correlation Fresh weight leaves shoot trunk  c o e f f i c i e n tv  Dry w e i g h t leaves shoot trunk  roots  injury  .64*  .76*  07  .44.  .65*  .83*  initial R  .21  .29  60*-  .11  25  .31  -.29  .07  -.30  photosynthetic rate .26  -.19  26  change R  *  = significant  at  -.24  ambient  •^Change i n z  Leaf  06  55  .02  59 .11  -.30  -.24  -.30  -.36  22  -.06  .20  .41  .59  5%  air,  stomatal  injury  ^Stomatal  3.5  (LAN)  to  6.6 / * E cm  resistance 24 h o u r s  resistance  at  after  after  start  of  ~1  min  PAR  2 hours,  a 6 hour ozone  0.75  ppm ozone  fumigation  fumigation  w i t h 0.75  w  Change in R s_  ppm ozone  x  Initial^ R .63*  04  level - 2  in  .53  -.05  in  v n = 10,  w  Photosynthetic roots rate  39  Table  9.  'Ives': injury,  simple c o r r e l a t i o n s of growth, and s t o m a t a l b e h a v i o r , S e p t e m b e r .  Correlation Fresh weight leaves shoot trunk  m j ury initial R s change in R  - .07  -.48  .23  78*  - .42  -.19  -.44  19  -.01  -.22  .61  - . 23  .74*  *  .26'"  = significant  at  Dry w e i g h t Photosynthetic* leaves shoot trunk roots rate  roots  33  photosynthetic rate . 53  v n = 9,  .  5%  x  in  ambient  Change  in  ^Stomatal z  Leaf  air,  3.5  stomatal  (LAN)  at  start  24 h o u r s  -.05  .76*  -.46 .10  g  .12  41  33  -.19  15  59  39  -.21  68*  58  -.27  41  -.46  34 •  52  Change in R  x  Initial^ R g  - .51  level  6.6 f j i cm  resistance  resistance  injury  to  29  .25  2 w  coefficient  1 min  after of  after  PAR  2 hours,  ozone  0.75  ppm ozone  fumigation  a 6 hour  fumigation  as  w i t h 0.75  ppm o z o n e .  77  there  was some i n d i c a t i o n o f  between  injury  negatively  and i n i t i a l  susceptibility, site  increase 1  Since i n i t i a l  leaf  weight,  entry,  whereby  susceptibility,  contrary  in  R  this  a s s o c i a t i o n between  m e d i a t e d by s t o m a t a  of p o l l u t a n t  correlation  R . g  correlated with  i n d i c a t e d an i n d i r e c t  a negative  may have  top  their  growth role  i n c r e a s e d top to  the  was  s  as  and the  growth  effect  seen  would in  Delaware'. In  'Concord'  correlations  vines  between  Relationships  injury  growth.  and growth  however,  a complex i n t e r a c t i o n  rates,  growth  (Table 10).  between  injury  larger  growth  and v a r i o u s  and i n j u r y  in vines with  trunks,  this  and i n j u r y  of  with a  higher  and r e d u c e d  T h e r e was no i n d i c a t i o n t h a t  interaction  significant  s u g g e s t e d the p o s s i b i l i t y  between  tendency toward  photosynthetic  t h e r e .were no  between p h o t o s y n t h e t i c r a t e  growth p a r a m e t e r s ,  greater  also,  top  indirect  was m e d i a t e d by  stomatal mechanisms. Vine-to-vine  correlations, within  revealed a variety,  of  systems of  injury  s u s c e p t i b i l i t y , vine  In  cases,  all  loosely  growth,  and s t o m a t a l  behavior.  i n c r e a s e d ozone s u s c e p t i b i l i t y c o u l d be  t h o u g h t h e b a l a n c e between  from c u l t i v a r  thus  a s s o c i a t i o n between  a s s o c i a t e d w i t h some f o r m o f  photosynthesis  cultivars,  growth  growth  dependent  o r on r e s e r v e s s t o r e d i n to  cultivar  the  (see T a b l e 1 1 ) .  increase, on  current  trunk  varied  Table  10/  'Concord': s i m p l e c o r r e l a t i o n s between g r o w t h , i n j u r y , and s t o m a t a l b e h a v i o r , S e p t e m b e r . Correlation  *  x  in  .01  -.05  .48  .01  55  -.40  24  .11  .35  -.46  .28  .16  .30  -.49  28  - .19  - .03  15  -.22  -.18  .07  .02  -.22  -.19  19  - . 28  -.49  .69*  .72*  at  level  - . 72*  = significant  ambient  Change  in  ^Stomatal z  Leaf  air,  3.5  stomatal  51  (LAN)  to  6. 6 f*E cm  resistance  resistance  injury  Change in R  .02  2 w  w  .51  photosynthetic rate - . 59*  vn = 11,  Photosynthetic roots rate  -.02  -.04  initial R s change in R  v  Dry w e i g h t leaves shoot trunk  Fresh weight leaves shoot trunk roots m j ury  coefficient  at  start  24 h o u r s  1 min  after of  after  -.22  PAR 2 hours,  ozone  0.75  ppm ozone  fumigation  a 6 hour  fumigation  w i t h 0.75  ppm ozone  x  Initial^ R -.01  Table  Summary o f i n d i c a t i o n s from vine-to-vine correlations, within cultivars  11.  C o r r e l a t i o n w i t h ozone i n j u r y Cultivar  susceptibility  Growth P a r a m e t e r Top wt  Trunk wt  Photosynthetic rate  Stomatal  Behavior  Initial R  Change i n R_ s  x  Ives  +  Concord  -  +  +.  0  0  Delaware  +  -  0  + .  0  v  w  •  w  +,  positive;  in  ambient  stomatal ^change  -,  air,  negative;  +  0,  no  correlation  to  6.6 yW.E cm ^min  resistance  at  start  resistance  7  0  3.6  in stomatal  V  of  ozone  after  PAR fumigation  2 h,  0.75  ppm ozone  80  DISCUSSION The p r o t e c t i v e exposure  against  previously Dunning  a pretreatment  a subsequent  and W i l t o n  effect  of p r i o r  (1965)  and H e a g l e  itself  of  acute  o b s e r v e d by M a c d o w a l l  (1967),  previous  effect  et  cases,  and Heck  however,  an a c u t e  dose.  The r e s u l t s  between  interaction  and s u b s e q u e n t a c u t e The e x i s t e n c e assessment of  first  of  this  visible  dose f o r  of  consideration levels several  are  every  d e s c r i b e d here reported  of  magnitude  injury, of  a  pretreatment  exposures  acute  above t h a t  the  visible the  the the  that  field dose  above  total  calculated threshold.  e x p o s u r e must be q u a l i f i e d  below  to  of  e p i s o d e s be  ozone e n v i r o n m e n t ,  in  case of  n o r c a n the  the  Likewise,  in for  r e s p o n s e means  of  days p r i o r  these  dose was  ozone e p i s o d e i n  a series  s i m p l y by summation o f The e f f e c t  Macdowall  each o f  sub-acute  type  c a n n o t be b a s e d s i m p l y on the  effective  and  exposure.  an a c u t e  for  In  been  A predisposing  the p r e t r e a t m e n t  significant  threshold  (1969).  (1974).  the  the  Heck  e x p o s u r e has b e e n o b s e r v e d by  b e a n and m i n t r e p r e s e n t  the  e x p o s u r e has  (1965),  al.  ozone  injury  acute  laboratory  examine  the  response to  acute  specify  the  ozone e n v i r o n m e n t  even i f  threshold,  by  exposure for  at  least  exposure.  experiments  designed  exposure,  researchers  i n which p l a n t s  were  to must grown  81  prior  to  acute  filtered  air  o r ambient  may e v i d e n t l y the  acute  exposure.  have  air,  a large  in  this  effect  concentrations questionable  and f r e q u e n c y ,  (Bennett  air  acclimation  or  et  al.,  1974).  on t h e  to  sub-acute  air  treatment  during  on p l a n t s  for  to  tolerance  low  Experiments  that  the  the  environment, response  to  the  switch  from  air  was,  the  course of  levels  or  low  filtered  course  to in  the  effect  or  effect  ozone to not  on s u s c e p t i b i l i t y  filtered  dehardening,  protective  low  ozone  This  the It  the  indicated  major  atmosphere.  ozone  from showed  environments  of  however,  of p l a n t  . ' had a  switch  that  component  appeared,  interaction  from  low  hardening, the  that  observed t h e r e was  age w i t h the  response  pretreatment.  The e f f e c t s primary  was  effect.  some a d d i t i o n a l to  air.  than  leaves  o f p r e t r e a t m e n t w i t h low  o f bean c a n be d i v i d e d  fil-  selected  were r a i s e d  low  of  experiments  ozone e n v i r o n m e n t s  air  an  of  or n a t u r a l l y the  of  represented  was the major component of the s u s c e p t i b i l i t y change and larger  is  between  or a d e b i l i t a t i n g the  air,  therefore,  difference  during  acclimated  ozone  ozone  filtered  It  i n w h i c h bean p l a n t s  filtered  of  ozone p r e t r e a t m e n t  (hardening)  (dehardening)  seed i n  charcoal-  sub-acute pretreatment  low ozone l e v e l s  experiments  tered  on p l a n t  found i n  g r e e n h o u s e - r a i s e d beans w h e t h e r  the  growth  in nature,  as low as t h o s e  obvious from r e s u l t s  filtered  between  exposure.  The e x t e n t  not  The d i f f e r e n c e  into  ozone on three  the  stages.  82  First,  a stage  of p r e d i s p o s i t i o n ,  protection,  and a t h i r d  These t h r e e  s t a g e s may be r e l a t e d  in primary  leaves  time when the at  of  stage,  bean,  leaves  are  a t i m e when e x p a n s i o n  stage  o c c u r s at Under  the  the  of  throughout  21-day  matured,  begun t o  the  s i n c e the  first  stage  is  expanding,  reaching  21 d a y s ,  its  conditions  primary period  The l o w e r  plants  at  of  susceptibility  the  features  still  leaves after that  the  in  sowing.  raised  in  filtered  A simple protective after  14  occurring  air  low o z o n e ,  on s u s c e p t i b i l i t y and l a t e r  explanation  of  ozone  either  days f r o m sowing response to  (Fig.  the  would  as a  have  prolongation  tissue, of  and r e m a i n i n g parallel  difference  Z)  as  or  the  tissue.  response to 12  third  pretreated  achievement  switched to  this  process occurring in  in  of  a s s o c i a t e d w i t h more j u v e n i l e  a s s o c i a t e d w i t h more mature  show an e f f e c t  occurs  increase  Ultimately,  may be v i e w e d  from seed i n  a  the  susceptibility  susceptibility  d i d not  thesis,  c o n t i n u e d to  s e n e s c e n c e and more C r ) a p i d  raised  o c c u r s at  second stage  this  an a c c e l e r a t e d  Plants  development  complete.  susceptibility  therefore,  of  maximum,' and t h e is  leaf  of  by p r e d i s p o s i t i o n .  other  we c a n e x p e c t  decrease.  characterized  time when e x p a n s i o n  susceptibility  leaves  also  by a s t a g e  to  experimental  the  followed  low  to  there,  those  ozone.  would d e s c r i b e low ozone  exposure  and an a n t a g o n i s t i c  low ozone e x p o s u r e  earlier  a  (Fig.  process 12  Y).  83  Process  Z , which p r o t e c t s  injury,  w o u l d be i n d u c e d by growth  after  the  8-14  maintained process, of  day growth  Y, which acts  from a c u t e in  low ozone  and w o u l d be  The  antagonistic  counter to  the  effect  Z , w o u l d be p r o d u c e d i n r e s p o n s e to  itself  a slightly  major  Thus,  to  if  role  concentrations effect  of  stage.  protective  is  a plant  that  to  growth  Process  property,  s u p p r e s s the  i n development,  low ozone e x p o s u r e s l a t e r  in  Y has although  effect  had b e e n e x p o s e d t o  early  ozone  stage  through m a t u r i t y .  low ozone p r i o r  its  plants  of  Z.  low ozone the in  protective  development  w o u l d be n e g a t e d . This  time-dependence i n  acute pretreatment  gives  Bean p l a n t s  ment where t h e ppm f o r  the  effective. to  the  response to  some s u p p o r t to  i n d i c a t i o n that hardening is here.  the  the  must g e r m i n a t e  i n an e n v i r o n -  ozone c o n c e n t r a t i o n i s below  protective  p r o c e s s t o be  0.02  optimally  This suggests a seasonal dimension  hardening p r o c e s s ,  in  the  operative process  whereby p l a n t s  o f b a c k g r o u n d ozone c o n c e n t r a t i o n s below early  sub-  the  in  0.02  s e a s o n w o u l d be more r e s i s t a n t  c o m b i n e d s u b - a c u t e and a c u t e  areas  exposures l a t e r  ppm to in  the  84  o co CO  Juvenile  8-14 Days  Mature  Leaf Age F i g u r e 12.  Model of ozone pretreatment mechanism. E f f e c t of exposure.to ozone pretreatment at j u v e n i l e stage ( Y ) , mature stage ( Z ) , and both j u v e n i l e and mature stages (YZ) on s u s c e p t i b i l i t y to acute ozone i n j u r y .  85  season than p l a n t s levels  of  in  ozone were more  This  where h i g h  between  experiments  r a i s e d and f i l t e r e d  grape  the  experiments  list  to  for  some o f  with  air-raised  may a l s o be added t o  background  continuous.  phenomenon may a c c o u n t  difference  the  areas  g-reenhouse-  bean p l a n t s . of  cautions  those w i t h bean..  allowed  leaf  have  reduced the  acute are  later  bean,  in  concentrations  above  0.02  to  acute  concentrations reduce  the  in  toward in  to  tibility  ambient  tendency  pretreatment  similar  under  that  injury, the  probability  of  protection  i n v i s i b l e , or  d i s c u s s e d by H e a g l e  ppm w o u l d then  If  interaction  grapes  the  increase higher  suscep-  pretreatment  chambers w o u l d  'Delaware'  chronic  and Heck  threshold  and i n j u r y  appearance tendency  of  of  to  a form o f  toward  this  injury  (1974)  injury  above  sub-  also  hardening.  r e s p o n s e c a n be e x p l a i n e d  additive  may  by  acute  by s e a s o n - l o n g s u b - a c u t e p r e t r e a t m e n t  a form of  This  were  conditions,  season.  period  increas'ing^pretreatment  open-top  The p r e d i s p o s i t i o n o f injury  the  comparing  The  May to m i d - J u n e , when g r a p e v i n e s out  It  in  from e a r l y to  the  that  response i n  to  that  and M a c d o w a l l  the  The  (1965).  than  visible  threshold,  synergism.  indicated  similar  by a g r e a t e r below  ozone  giving  the  greater  ozone-tolerant  plants  86  may be e x p l a i n e d acclimation  as an i n c r e a s e d p o s s i b i l i t y  in ozone-sensitive  assumption that  plants,  increased s e n s i t i v i t y  of  under to  the  ozone  injury  may be a s s o c i a t e d w i t h some p h y s i o l o g i c a l b a s i s a protective In  for  response.  particular,  as a b a s i s past  for  this  s p e c u l a t i o n about  of  episodes  (1965)  toward  communication)',  observed t h i s  same t r e n d  with pretreatment Both of  these  the  of pretreatment Results the  effect  field, lower  later  in  effect.  exposures  described in  on s t o m a t a l  speed of  effect  have  tective  aspect  of  the  of  a  d o s e s had  while  higher  experiments  is  the  partly  this  thesis  also  is  effect into  a  ozone e x p o s u r e . of  effect effect.  suggest  and an e f f e c t  effect  results  protective  of pretreatment  stomatal  ppm.  their  a stomatal  The s t o m a t a l  acute  as 0.03  interpreted  that  resistance,  r e s p o n s e to  stomata  W. J o h n s t o n  laboratory  hypothesis  on s t o m a t a .  of  tobacco,  prior  doses,  ozone e x p o s u r e has b e e n d i v i d e d h e r e effect  with  c o n c e n t r a t i o n s , as low  protective  foundation  w o r k i n g w i t h s o y b e a n , has  researchers  as s u p p o r t i n g  has been the  observed e f f e c t  the  doses had a p r o t e c t i v e  (personal  its  in  hypersensitivity  possible role  concluded that  a predisposing effect  that  the  B a s e d on t h e  acute  Macdowall  prior  concept of  ozone p r o t e c t i o n  in acclimation. series  for  due  of  to  low  general on The  the pro-  pretreatment  87  appears on the not  to b e , the speed o f  general  response to  r e a s o n a b l e to  stomata  is  effect,  not'the  acute  assume t h a t  ozone.  this  it  does a p p e a r  that  may be o v e r r i d d e n by t h e pretreatment  as t h e  the  behavior  c l o s u r e by a c u t e upon r e m o v a l o f  stomatal  The a s p e c t o f  of  ozone  stomatal effect  strated  experiments  in  the  of  a c h r o n i c dampening o f reversible of  in  ozone e x p o s u r e  is  Hill  this  stomatal  1  of  stomatal  rapidly  reversible  and L i t t l e f i e l d ,  thesis,  aperture This  1969)..  involved with  low ozone p r e t r e a t m e n t ,  upon ozone r e m o v a l .  demon-  appears  that  is  to  be  not  irreversible  type  r e s p o n s e has o c c a s i o n a l l y been n o t e d i n p r e v i o u s  experiments  (Macknight,  1968;  Koritz  The p o s s i b l e c o m b i n a t i o n o f induced c l o s u r e i n plants bean,  is the  l e d to  experiments  unclear. lower  degree o f  acute  exposure.  sible  type,  filtered  In  air.  these  two  1952).  types  of  ozone-  with greenhouse-raised  R  g  of  filtered  s u s c e p t i b i l i t y to stomatal Both of  however,  and Went,  experiments with g r e e n h o u s e - r a i s e d  initial  a greater  greater  in  of  b e h a v i o r which i s  the p r o t e c t i v e  on  concentration increases.  ozone t h a t (e.g.,  is  effect  i n v o l v e s an i n d u c t i o n o f  levels the  effect  predisposing effect  pretreatment  it  concentration  The most commonly n o t e d e f f e c t on s t o m a t a l  While  general  r e v e r s e d as p r e t r e a t m e n t  increases,  effect  air-pretreated  acute  injiury  and to  c l o s u r e i n r e s p o n s e to  these  effects  because a l l  are  of  plants  the  a  the irrever-  measurements were made  88  Theoretically, may be d i v i d e d closure  in  stomatal  into  three  r e s p o n s e to  type  of  carbohydrate  closure  perhaps  due t o  physiological closure  in  w i t h the damage  stomata.  the  as i n  The t y p e s  of  behavior  s u c h as was air  the  (1)  switched  to  to  susceptibility this  in  stomatal  susceptibility pretreatment, by a c u t e  the  ozone,  acute  In  when s u s c e p t i b i l i t y  (1), was  of  low  the  of  was  the  with  in  types  type  filtered Those  (1)  of  and  stomatal  the  stage,  In  of  concentrations  seven days.  reversible  the  the  measurement  progress  sub-acute  closure the  on  where  i n c r e a s e d by  decreased.  decreased,  physical  ozone p r e t r e a t m e n t  early  of  (3).  paralleled  e x p o s u r e was  magnitude  type  a single  of  associated  raised  closure  experiments  response.  to  in  type  experiments  w i t h beans  stomatal  types  surrounding  and  low ozone a f t e r  The e f f e c t s those  is  p r e s e n c e o f h i g h ozone  suggested that  ozone.  in similar  closure requires  experiments  exposures,  and d i r e c t  (2)  in  irreversible  sub-acute  tissues  of  or  an i r r e v e r s i b l e  probably  may be p r o g r e s s i v e s t a g e s  response  in  are  changes  an  c l o s u r e observed in  type  in  done i n  arid t h e n  experiments (2)  of  (2)  lesions  and m e s o p h y l l i c  type  structure  exposures which  epidermal  Examination  to  changes  (3)  necrotic  g r e e n h o u s e - r a i s e d beans  stomatal  (1);  acute  of  (due  long-term of  ozone  a reversible  etc.;  accumulation  r e s p o n s e to  (1)  r e s p o n s e to  s u c h as membrane  content,  factors  in  exposure  i n r e s p o n s e to  appearance  to  types:  acute  physiological properties activity,  closure  induced  second s t a g e ,  irreversible  type  of  89  closure  i n d u c e d by s u b - a c u t e e x p o s u r e ,  This to  the  p r o g r e s s i o n from a r e d u c t i o n  appearance of  type  elucidate  whether  the  is  i n both  cases.  active  (2)  the  changes.  ability  to  a later  of  stomatal  stage  the in  of  The two  stomata  on s t o m a t a l  a significant  data  on s t o m a t a l  t e n d e d t o have  air-pretreated  plants  no c h a n g e , o r  a slight  environmental  was  no s i g n i f i c a n t  dampening  b e h a v i o r were o b s e r v e d . treatment  effect  the at  a lower  (type  the  effects  (2)  tolerant  the  plants  initial  in  the  R  g  In  'Delaware'  closure in ozone-pretreated  the  cultivar,  trends  in  (ambient  essentially of  that  however, plants  air  filtered  closure  (1)).  on s u s c e p t i b i l i t y  grapevines,  In  low  susceptibility,  than  extent  (type  on b e a n ,  of  time o f p r e d i s p o s i t i o n ,  closure), with  reduction  results  on  In  the  i n the  a p p e a r e d t o be a s s o c i a t e d w i t h changes i n  (2)  stage  decreased  was a more g e n e r a l  ozone-pretreated  low ozone p r e t r e a t m e n t  type  respond to  t o h i g h ozone c o n c e n t r a t i o n s  compares w i t h  closure.  by  ozone p r o g r e s s i v e l y  ozone i t s e l f  behavior  treatment)  stages  to  'Delaware',  showed t h a t  of  to  experiments,  September,  this  to  s t a g e s may be e x p l a i n e d  whereby  i n which there  p r e d i s p o s i t i o n of  response  help  same s y s t e m o f p h y s i o l o g i c a l changes  sensitivity  grapevine  case of  the  (1) c l o s u r e  function.  ozone t r e a t m e n t only  type  had a p p e a r e d .  The d e s e n s i t i z a t i o n w o u l d move f r o m an e a r l y  i n which stomatal  In  in  (2),  c l o s u r e does n o t  a s i n g l e mechanism, however, reduces  type  and a  part, effect  later  type  there  in  was  (2) less  greater  90  susceptibility was more t y p e lesser  to  a c u t e ozone i n j u r y ,  Ignoring  the  the  acute  effects  c o n c e n t r a t i n g on t h e in  of  the  ranking of  (cf.  The s t o m a t a l  to  ozone i n j u r y  relative  about  the  acute  injury  data  an e q u i v a l e n t Based on t h e  the  sensitivity  in  intermediate the  t r e n d was  type in has  (1)  (Table  field,  between for  and  stomatal  ranking of  the  and t y p e  'Concord'  due t o  and  the  a slight (2)  cultivars  r e s p o n s e and b a s e d on  'Ives'  cultivars  absence of  there  any in  i n both  for  be  cultivars.  a c c o r d i n g to  and injury  m i g h t be e x p e c t e d t o In  'Ives'  a slight  d i s a p p e a r e d , a n d , more i m p o r t a n t l y ,  the  both  tendency seen  decrease i n type the  be  'Concord',  d e c r e a s e , o r no c h a n g e , i n In  the  appeared to  and ' D e l a w a r e ' .  closure.  'Delaware'  seem t o  B a s e d on t r e n d s 3)  the  cultivar  r e s p o n s e s , however,  'Concord'  'Ives'  of  general  does n o t  (1)  behavior.  tendency toward p r o t e c t i o n  s u p p o r t e d by t h e  type  any,  stomatal  'Concord'  effects.  i n August  ranking of  'Delaware'  if  the  stomatal of  of  and  grape  low ozone p r e t r e a t m e n t  a r e . a good d e a l more t e n u o u s , significant  to  field,  relation  r e s p o n s e to  responses i n  statistically  the  same a s p e c t s o f  Conclusions susceptibility  in  three  degree o f  basis,  r e s p o n s e , though r e l a t e d  be b a s e d on the  the  4).  the  ozone t o l e r a n c e  closure  Table  and a  injury.  to be a s s o c i a t e d w i t h a g r e a t e r  sensitivity  there  low ozone p r e t r e a t m e n t ,  general  field,  ozone  appears  pretreatment  i n bean  (2) c l o s u r e i n ozone-pretreated p l a n t s  s u s c e p t i b i l i t y to  cultivars  while  reduction in  (1) type  91  (2)  closure  ('Ives')  ('Concord'), closure effect in  reveals  a trend  an i n c r e a s e i n  toward  The t r e n d  toward  stage of  two  stomatal  the  i.e.,  this  types  conclusion is  of  stomatal  likely  that  i.e.,  type  type  (2)  (the  c l o s u r e , or  closure),  the  coupling acclimation  ozone c o n c e n t r a t i o n s a c c o m p a n y i n g growth with i r r e v e r s i b l e  it  the  latter  protective  to  the  address t h i s  reduction.  that  this  afford  the  the  was n o t  the p r e s e n c e o f no s i g n i f i c a n t  experiments the  more  is  best  that possibili  without  protection  would  appear  reductions  were n o t  with  an  adequate  grapevines  case. basis,  stimulation.  susceptibility  the  stomatal,aperture  a predisposition effect a growth  appears  field,  bean e x p e r i m e n t s  On a c u l t i v a r - t o - c u l t i v a r absence of  of  irreversible  The a s s o c i a t i o n o f  dampening o f  point,  that  c o m b i n a t i o n o f h i g h and low  encountered i n  While  clear  however,  an a s s o c i a t i o n o f p r o t e c t i o n w i t h  growth.  is  long-term  The p a r a d o x h e r e ,  for  indicated  long-term  h y p e r s e n s i t i v e mechanism,  h y p e r s e n s i t i v e mechanism seems t o  in plant  increases  b e h a v i o r w h i c h may be a s s o c i a t e d  (1)  to be i n v o l v e d .  support  (2)  protective  toward  observed at  the  the  increasing  speculative,  susceptibility  changes i n  effects,  to  type  response i n beans.  w i t h changes i n  to  closure  c l o s u r e i n d u c e d by  exposures, s i m i l a r  While  to  (2)  w o u l d thus be a c c o m p a n i e d by a t r e n d  level  the  type  ('Delaware').  irreversible  low  and a b s e n c e o f  effects  it is  appears  only  associated with  Since there in  that  the  two  were  also  cultivars  92  w h i c h showed s i g n i f i c a n t be no f i r m growth  c o n c l u s i o n s about  stimulation  ozone e f f e c t s however,  existence of  the August h a r v e s t of  increase  the  throughout  stimulation  of  July harvest,  and t h e  extent  season progressed ( F i g . of  the  growth p a r a l l e l e d  susceptibility  to  the  acute  growth  Since so  little  it  really  in  reductions  that  14).  In  for  this  'Ives' while  effect  effect of  of the  (Table  at  the  low ozone on effect  3),  ozone et  the  on  i n a manner stimulation injury.  al.  in  1974,  stimulation  of  plant  that  there  the p o s s i b l e  response.  t h e s i s was b a s e d on work  (1977)  to  both c u l t i v a r s ,  s p e c u l a t i o n about  i n d u c e d by e x p o s u r e t o  ozone-  d e c r e a s e d as  low ozone c o n c e n t r a t i o n s  and R u n e c k l e s  the  The o z o n e - i n d u c e d  from acute  this  tops  continued  a s s o c i a t i o n between  work has b e e n done on t h e  Bennett  13),  development  ozone i n j u r y  p h y s i o l o g i c a l mechanisms o f tested  in  was p o i n t e d out by B e n n e t t  no b a s i s  relationship.  growth was g r e a t e s t of  and p r o t e c t i o n  growth by e x p o s u r e to is  this  growth  stimulatory  which suggested a p o s i t i v e leaf  (Fig.  in  susceptibility,  growing s e a s o n . leaf  can  a s s o c i a t i o n between  growth  'Ives'; root  'Concord'  seasonal p r o f i l e  of  of  there  The s e a s o n a l t r e n d s  and a c u t e  stimulation  induced s t i m u l a t i o n  leaf  a positive  growth  do s u g g e s t t h e  appeared at  on g r o w t h ,  and p r o t e c t i o n .  on v i n e  The g r e a t e s t  the  effects  One p o s s i b i l i t y  involving  growth  low ozone c o n c e n t r a t i o n s . e x p l a i n e d the  fact  that  93  or-  6  -P -P  o o  CO  O  •o  O  o-  -O'  C\J  E o ccj  u  < <H  cd  Aug  Sept  l x J  July  Aug  Sept  Time o f Y e a r ' Growth o f p o t t e d ' I v e s ' v i n e s i n a m b i e n t a i r (•) or c h a r c o a l - f i l t e r e d a i r ( o ) . Fresh weightC—) and d r y - w e i g h t (--•> o f l e a v e s ( A ) , s h o o t s ( B ) , and r o o t s ( C ) ; and l e a f a r e a ( D ) . D a t a f r o m T a b l e 5-  94  o  I  -J  Aug  Sept  July Time  of  Aug  Sept  Year  Growth o f p o t t e d ' C o n c o r d ' v i n e s i n ambient a i r (•) or c h a r c o a l - f i l t e r e d a i r (o). F r e s h weight (—) and d r y w e i g h t (—) o f l e a v e s ( A ) , and r o o t d r y w e i g h t r a t i o ( B ) . D a t a f r o m T a b l e k.  95  reduced l e a f  areas  in clover  and r y e g r a s s  i n response to  low ozone e x p o s u r e s were a c c o m p a n i e d by e q u i v a l e n t  or  s l i g h t l y h i g h e r NAR's by c o n c l u d i n g t h a t  a compensation  occurred  of  area.  i n NAR t o  To e x p l a i n t h e  with potted  reaction  to  this  cuttings  of  the  b e c a u s e growth  effect  of  type used f o r in  the  area  ozone on  in  leaf  experiments  c o m p l e m e n t a r y h y p o t h e s i s was a r e a was a c o m p e n s a t o r y  ozone i n  This p o s s i b i l i t y is  the  on e x i s t i n g  effect  increased leaf  a primary  species.  the  increased leaf  grapevines,  developed that  this  counteract  the  not  d e c r e a s i n g NAR i n  unreasonable  grapevine  experiments,  s e a s o n o b s e r v e d was h i g h l y  carbohydrate reserves.  If  in  dependent  mobilization  of  t h e s e r e s e r v e s was c o n t r o l l e d by some f e e d b a c k mechanism r e g u l a t e d by p r o d u c t i o n o f p h o t o s y n t h a t e the  c a p a c i t y might  conditions  September h a r v e s t ,  to  however,  rates  or  filtered  have b e e n a b e t t e r  compensation e f f e c t ,  the  assumption of  area  photosynthetic There  is  a leaf  under  on v i n e s  from  r e v e a l e d no d i f f e r e n c e s air.  t h a t measurements made e a r l i e r  season might  leaves,  current photosynthesis.  of photosynthetic  t r e a t e d w i t h ambient  possible  the  t o . p r o d u c e more new growth  more u n f a v o r a b l e  Measurements  vines  exist  in  in  While the  i n d i c a t i o n of  results  do n o t  between it  a possible  support  this  rate. this  type  of  is  growing  i n c r e a s e b a s e d on r e d u c t i o n s  no e v i d e n c e t h a t  the  long-term  in  96  adaptation  of  grapevines  to  reflected  in  immediate  reductions  aperture,  or p h o t o s y n t h e s i s .  from the  i n c r e a s e d growth  exposure which  into  is  While  acute  assumptions ozone-free  use o f  the  ozone-tolerance  the  air  formative  in  in  this  into  P e r h a p s t h e most  of  is  the  re-evaluate.,  acclimation,  the  is  results  of  crop p l a n t s .  d e s i g n e d to  a l s o be  there  need to  the  into  experiments  important  stomatal calls  such  on growth  influence  ozone  a r e a s where  necessary.  While  sub-acute  question widespread  that  is  must  distinct  experiments  evolutionary  thesis  s u g g e s t a number o f  tolerance  by  occurrence of  research these  stomatal  term a c c l i m a t i o n  filtered  any  of  environments.  The i n d i c a t i o n s may o c c u r  a c c o m p a n i e d by  ozone t o l e r a n c e ,  must n e c e s s a r i l y c a l l about  is  T h i s phenomenon i s  shorter  ozone s u s c e p t i b i l i t y ,  stimulations  rates,  concentrations,  a c c o m p a n i e d by a dampening o f this  q u e s t i o n the  acute  i n acute  i n d u c t i o n of  function.  low ozone  past  in  additional immediately  the  attempts  at  New s u r v e y s and  exploit  the  acclimation  light  urgent  of  possible  breeding  ozone  selection  possibility  of  acclimation  undertaken.  stomatal factor  e x c l u s i o n has b e e n shown h e r e  i n some i n s t a n c e s  a l s o a need f o r  additional  of  ozone  to  mechanisms o f  p r o t e c t i o n w h i c h may be i n d u c e d by e x p o s u r e to concentrations.  an  acclimation,  experiments  question of p o s s i b l e non-stomatal  to be  low  explore ozone ozone  9 7  A d d i t i o n a l work i s a l s o n e c e s s a r y  to e l u c i d a t e the  r e l a t i o n s h i p between ozone a c c l i m a t i o n  and g r o w t h .  evident  from acute  a s s o c i a t i o n between p r o t e c t i o n  and.long-term illustrates  irreversible  the p o s s i b i l i t y  a c u t e ozone t o l e r a n c e while  the i m p l i e d  greater stomatal of  closure  o f stomata,  of a necessary  The injury  i n bean,  tradeoff  between  and o v e r a l l p o t e n t i a l p r o d u c t i v i t y ,  relationship of increased  ozone t o l e r a n c e ,  i n grapevines,  e f f e c t s , suggests  the existence  growth and  independent o f of other  forms  a c c l i m a t i o n w h i c h may be p o t e n t i a l l y more u s e f u l .  98  SUMMARY  1.  Sub-acute the  ozone e x p o s u r e s  development  subsequent  2.  of v i s i b l e  acute  injury  form  of  either  from  injury  or p r e d i s p o s i t i o n  to  greater  the  pretreatment  doses l e d  The p r o t e c t i v e as h a r d e n i n g ,  to  doses l e d  of  this  effect  the  course of  t h a n as a p r e d i s p o s i n g e f f e c t  in bean,  the  exposure  effect  passed through  5.  The f i r s t w i t h the  of  stages  effect  of  p r e d i s p o s i t i o n was stomatal  closure  in  to  the of  In while  may be  filtered  increased  in  that  of  change  to  increased,  acute  stage  decreased  of  increased  susceptibility,  associated  on s t o m a t a .  a s s o c i a t e d with a reduced r e s p o n s e to  injury  susceptibility.  r e s p o n s e were  pretreatment  rather  air.  ozone  an e a r l y  stage  described  experiments,  sub-acute  stages:  a middle  stage  two  injury.  protection  on s u s c e p t i b i l i t y  three  susceptibility, and a l a t e r  to  protection  o b s e r v e d as an o z o n e - i n d u c e d  time o f  to  predisposition.  aspect  occurring during  As the  on  exposures.  may t a k e  lower  effect  response  effect  higher  4.  in  This  bean,  3.  had a s i g n i f i c a n t  acute  ozone  The  early  tendency exposure,  for  w h i l e the p r o t e c t i v e stage was a s s o c i a t e d with a general stomatal c l o s u r e , independent  o f acute  exposure.  Pretreatment doses which had a s i g n i f i c a n t effect  protective  i n bean i n c r e a s e d the acute ozone suscep-  tibility  o f mint c u t t i n g s s l i g h t l y .  In grape, season-long sub-acute  exposures  to ozone  had a s t i m u l a t o r y e f f e c t on p l a n t growth i n 2 of 3 cultivars  tested.  no e f f e c t  o f ozone on growth, vines were p r e d i s p o s e d to  acute i n j u r y cultivars,  In the t h i r d c u l t i v a r , which showed  by sub-acute pretreatment.  there was some i n d i c a t i o n  Comparing  that an i n c r e a s i n g  trend toward p r o t e c t i o n by sub-acute pretreatment may have been a s s o c i a t e d with the same type o f stomatal c l o s u r e observed i n bean. some i n d i c a t i o n  Within c u l t i v a r s ,  there was  that growth s t i m u l a t i o n may have been  a s s o c i a t e d with i n c r e a s e d acute s u s c e p t i b i l i t y at the end o f the growing tibility  season, and decreased acute suscep-  at mid-season.  Experiment  Summary  Plant  Treatment Ozone Concentration  Conditions Duration (days)  Environment P r i o r to T r e a t m e n t  E f f e c t s of Treatment ( c o n t r o l s exposed to c h a r c o a l filtered air)  (PP ) m  Bean (treatments beginning 8 days a f t e r sowing)  .02  7  greenhouse  decrease i n acute s u s c e p t i b i l i t y  .02-.10  7  greenhouse  increase i n acute s u s c e p t i b i l i t y with i n c r e a s i n g dose  .02  7 filtered  ,.02  air  14 filtered  air  increase i n acute susceptibility. decrease i n stomatal c l o s u r e i n d u c e d by a c u t e ozone e x p o s u r e decrease i n acute susceptibility. increased stomatal resistance in f i l t e r e d a i r p r i o r to acute e x p o s u r e and t h r o u g h out a c u t e e x p o s u r e  .02  7  filtered  air  no e f f e c t height  on  stem  .02  14  filtered  air  no e f f e c t height  on  stem  Experiment  Summary  (continued)  Plant  Treatment Ozone Concentration  Mint  Conditions  'Ives'  Grape cv  'Concord'  Grape cv  'Delaware'  Effects of Treatment ( c o n t r o l s exposed to c h a r c o a l - f i l t e r e d air)  Duration (days)  .02  Grape cv  Environment P r i o r to Treatment  greenhouse  small acute  increase in susceptibility  1-3  months  ambient  i n c r e a s e d g r o w t h , no e f f e c t on a c u t e s u s c e p t i b i l i t y or stomatal behavior  "  1-3  months  ambient  i n c r e a s e d g r o w t h , no e f f e c t on a c u t e s u s c e p t i b i l i t y or stomatal behavior  "  1-3  months  ambient  no e f f e c t increased tibility, stomatal  see T a b l e  1  on g r o w t h , acute suscep no e f f e c t on behavior  102  LITERATURE  CITED  A s h e n d e n , T . W . , and T . A . M a n s f i e l d . 1977. Influence of w i n d s p e e d on t h e s e n s i t i v i t y o f r y e g r a s s t o SO . J . Expt. Bot. 28:729-735. B a r n e s , R . L . 1972a. E f f e c t s o f c h r o n i c e x p o s u r e to ozone on p h o t o s y n t h e s i s and r e s p i r a t i o n o f p i n e s . E n v i r o n . P o l l u t . 3:133-138. B a r n e s , R . L . 1972b. E f f e c t s o f c h r o n i c e x p o s u r e t o ozone on s o l u b l e s u g a r and a s c o r b i c a c i d c o n t e n t o f p i n e seedlings. Can. J . Bot. 50:215-219. Bell,  J . N . B . , and W . S . C l o u g h . 1973. Depression of i n r y e g r a s s exposed to s u l p h u r d i o x i d e . Nature 241:47-49.  B e n n e t t , J . P . , and R . J . O s h i m a . 1976. y i e l d response to ozone. J . Amer. 101:638-639.  yield  C a r r o t i n j u r y and Soc. Hort. S c i .  B e n n e t t , J . P . , H.M. R e s h , a n d V . C . R u n e c k l e s . A p p a r e n t s t i m u l a t i o n s o f p l a n t growth by pollutants. Can. J . Bot. 52:35-41.  1974. air  B e n n e t t , J . P . , and V . C . R u n e c k l e s . 1977. E f f e c t s o f low ozone on growth o f c r i m s o n c l o v e r and a n n u a l r y e g r a s s . Crop S c i . 1 7 : 4 4 3 - 4 4 5 . B l u m , V . , and D . T . T i n g e y . 1977. A s t u d y o f the p o t e n t i a l ways i n w h i c h ozone c o u l d r e d u c e r o o t growth and nodulation of soybean. Atmos. E n v i r o n . 11:737-739. B o b r o v , R . A . 1952. The e f f e c t oat l e a v e s . Phytopathol.  ./  o f smog on the 42:558-563.  anatomy  of  s  B o n t e , J . , C . B o n t e , L . De. C o r m i s , and P. Lduge.t. 197 7. C o n t r i b u t i o n a 1 ' e t u d e des c a r a c t e r e s ^ d e r e s i s t a n c e de P e l a r g o n i u m a un p o l l u t a n t a t m o s p h e r i q u e , l e d i o x y d e de s o u f r e . P h y s i o l . Veg. 15:15-27. B r e w e r , R . F . , and G. F e r r y . 1974. E f f e c t s of a i r p o l l u t i o n on c o t t o n i n the San J o a q u i n v a l l e y . Calif. Agric. 28:6-7.  103  Chambers, L . A . 1976. C l a s s i f i c a t i o n and e x t e n t o f a i r p o l l u t i o n problems, p p . 3-22 In A . C . Stern (Ed.) A i r P o l l u t i o n V o l . I. A i r p o l l u t a n t s : Their t r a n s f o r m a t i o n and t r a n s p o r t . Academic P r e s s , N.Y. C h a n g , T . Y . , and B. W e i n s t o c k . 1977. Net ozone formation i n r u r a l atmospheres, p p . 451-461 In I n t e r n a t i o n a l C o n f e r e n c e on P h o t o c h e m i c a l O x i d a n t P o l l u t i o n and i t s c o n t r o l . Proceedings. Vol. I. E c o l o g i c a l R e s e a r c h S e r i e s , O f f i c e o f R e s e a r c h and Development. E.P.A.--600/3-77-0019. C o f f e y , P . , W. S t a s i u k , and V . Mohnen. 1977. Ozone i n r u r a l and u r b a n a r e a s o f N . Y . S t a t e . p p . 8 9 - 9 6 , In. I n t e r n a t i o n a l C o n f e r e n c e on P h o t o c h e m i c a l O x i d a n t P o l l u t i o n and i t s C o n t r o l . Proceedings. Vol. I. E c o l o g i c a l Research S e r i e s . O f f i c e o f R e s e a r c h and Development. E.P.A.--600/3-77-0019. Craker, L . E . 1972. D e c l i n e and r e c o v e r y o f p e t u n i a f l o w e r development from ozone s t r e s s . H o r t . S c i . 7:484. D a v i s , D . D . , and F . A . Wood. 1973. The i n f l u e n c e o f e n v i r o n m e n t a l f a c t o r s on the s e n s i t i v i t y o f V i r g i n i a P i n e to o z o n e . Phytopathol. 63:371-376. Dean,  C.E. 1972. Stomate ozone-induced weather 12:547-548.  d e n s i t y and s i z e as r e l a t e d t o fleck in tobacco. Crop S c i .  D i m i t r i a d e s , B . , and A . P . A l t s h u l l e r . 1978. International c o n f e r e n c e on o x i d a n t p r o b l e m s : A n a l y s i s o f the evidence/viewpoints presented. P a r t II. Evidence/ v i e w p o i n t s on the key i s s u e s . J . A i r Pollut. Control Assoc. 28:207-212. D u g g e r , W.M. J r . , O . C . T a y l o r , E . C a r d i f f , and C R . Thompson. 1962. S t o m a t a l a c t i o n i n p l a n t s as r e l a t e d t o damage from p h o t o c h e m i c a l o x i d a n t s . Plant P h y s i o l . 37:487-491. D u n n i n g , J . A . , and W.W. H e c k . 1977. R e s p o n s e o f bean and t o b a c c o to o z o n e : E f f e c t of l i g h t intensity, t e m p e r a t u r e , and r e l a t i v e h u m i d i t y . J . Air Pollut. Control Assoc. 27:882-886. E n g l e , R . L . , and W.H. Gableman. 1966. I n h e r i t a n c e and mechanism f o r r e s i s t a n c e t o ozone damage i n o n i o n , A l l i u m c e p a L . P r o c . Amer. S o c . H o r t . S c i . 8 9 : 4 2 3 - 4 2 9 .  104  Eschenroeder, A . Q . 1977. Models f o r p r e d i c t i n g a i r quality. p p . 195-238 In Ozone and o t h e r p h o t o c h e m i c a l oxidants. National Research C o u n c i l ( U . S . A . ) . Committee on M e d i c a l and B i o l o g i c E f f e c t s o f Environmental P o l l u t a n t s . N a t i o n a l Academy o f Sciences. Washington, D.C. ISBN 0 - 3 0 9 - 0 2 5 3 1 4 . E v a n s , L . S . , and I . P . Ting. 1973. membrane p e r m e a b i l i t y c h a n g e s . 155-162. Evans, L . S . , leaves: transfer  Amer.  Ozone-induced Amer. J . B o t .  60:  and I . P . Ting. 1974a. Ozone s e n s i t i v i t y R e l a t i o n s h i p to l e a f w a t e r c o n t e n t , gas resistance,  J . Bot.  and  anatomical  of  characteristics.  61:592-597.  E v a n s g ^ L . S . , and I . P . Ting. 1974b. E f f e c t o f ozone on R b - l a b e l l e d potassium transport i n leaves of Phaseolus v u l g a r i s L. Atmos. E n v i r o n . 8:855-861. F e d e r , W.A. 1970. P l a n t r e s p o n s e to c h r o n i c e x p o s u r e o f low l e v e l s o f o x i d a n t t y p e a i r p o l l u t i o n . Environ. P o l l u t . 1:73-79. F e d e r , W . A . , and F . S u l l i v a n . 1969. Ozone: Depression o f f r o n d m u l t i p l i c a t i o n and f l o r a l p r o d u c t i o n i n duckweed. Science 165:1373-1374. F l e t c h e r , R . A . , N . O . A d e d i p e , and D . P . O r m r o d . 1972. A b c i s i c a c i d p r o t e c t s bean l e a v e s from o z o n e - i n d u c e d phytotoxicity. Can. J . Bot. 50:2389-2391. G l a t e r , R . B . , R . A . S o l b e r g , and F . M . S c o t t . 1962. A Developm e n t a l s t u d y o f the l e a v e s o f N i c o t i a n a g l u t i n o s a as r e l a t e d to t h e i r smog s e n s i t i v i t y . Amer. J . B o t . 49:954-970. H e a g l e , A . S . , D . E . B o d y , and W.W. H e c k . 1973. top f i e l d chamber t o a s s e s s t h e i m p a c t o f on p l a n t s . J . E n v i r o n . Q u a l . 2:365-368.  A n open air pollution  H e a g l e , A . S . , D . E . B o d y , and G . E . N e e l y . 1974. Injury and y i e l d r e s p o n s e o f s o y b e a n t o c h r o n i c doses o f ozone and s u l f u r d i o x i d e i n the f i e l d . Phytopathol. 64:132-136. H e a g l e , A . S . , and W.W. H e c k . 1971. Ozone i n j u r y to as i n f l u e n c e d by a i r v e l o c i t y d u r i n g e x p o s u r e . 61:1209-1212.  plants Phytopathol.  H e a g l e , A . S . , and W.W. H e c k . 1974. P r e d i s p o s i t i o n of t o b a c c o t o o x i d a n t a i r p o l l u t i o n i n j u r y by p r e v i o u s exposure to o x i d a n t s . E n v i r o n . P o l l u t . 7:247-252. Heck,  W.W. 1968. Factors i n f l u e n c i n g expression of o x i d a n t damage to p l a n t s . A n n . Rev. P h y t o p a t h o l . 6 :165-188.  Heck,  W.W., and J . A . D u n n i n g . 1967. The e f f e c t s o f o z o n e on t o b a c c o and p i n t o bean as c o n d i t i o n e d by s e v e r a l ecological factors. J . A i r P o l l u t . Control Assoc. 17:112-114.  Heck,  W.W., J . A . D u n n i n g , and I . J . H i n d a w i . 1966. Ozone: N o n - l i n e a r r e l a t i o n s h i p o f dose and i n j u r y in plants. Science 151:577-578.  Heck,  W.W., J . B . Mudd, and P . R . M i l l e r . 1977. P l a n t s and microorganisms. pp. 437- 585 In. Ozone and o t h e r photochemical oxidants. National Research Council (U.S.A.). Committee on M e d i c a l and B i o l o g i c E f f e c t s of Environmental P o l l u t a n t s . N a t i o n a l Academy o f Sciences. Washington, D.C. ISBN 0 - 3 0 9 - 0 2 5 3 1 4 .  Heggestad, H.E. 1973. Photochemical a i r p o l l u t i o n i n j u r y to p o t a t o e s i n the A t l a n t i c C o a s t a l S t a t e s . Amer. Potato J . 50:315-328. H e g g e s t a d , H . E . , and W.W. H e c k . 1971. Nature, extent, and v a r i a t i o n o f p l a n t r e s p o n s e t o a i r p o l l u t a n t s . Adv. Agron. 23:111-145. H e g g e s t a d , H . E . , and J . T . M i d d l e t o n . 1959. c o n c e n t r a t i o n s as c a u s e o f t o b a c c o l e a f Science 129:208-209. Hill,  Ozone i n injury.  high  A . C , and N. L i t t l e f i e l d . 1969. Ozone: E f f e c t on a p p a r e n t p h o t o s y n t h e s i s , r a t e o f t r a n s p i r a t i o n , and stomatal closure jn.plants. Environ. S c i . Technol. 3:52-56.  Horsman, D . C , and A . R . W e l l b u r n . 1977. E f f e c t s of S 0 p o l l u t e d a i r upon enzyme a c t i v i t y i n p l a n t s o r i g i n a t i n g from a r e a s w i t h d i f f e r e n t a n n u a l mean atmospheric S0 c o n c e n t r a t i o n s . Environ. Pollut. 1 3 : 3 3 - 39,  2  ?  Hull,  H . M . , and F.W. Went. A i r P o l l u t . Symp. 2nd. i n H e g g e s t a d and H e c k ,  1952. pp. 122-128. O r i g i n a l not s e e n , 1971.  In P r o c . N a t . abstracted  106  J o h n s o n , W . B . , R . C . S k l a r e n , and D . B . T u r n e r . 1976. Urban a i r q u a l i t y m o d e l l i n g . p p . 503-562 In A . C . S t e r n ( E d . ) A i r P o l l u t i o n V o l . I. Air pollutants t h e i r t r a n s f o r m a t i o n and t r a n s p o r t . Academic P r e s s , N.Y. J u h r e n , M . , W. N o b l e , and F.W. Went. 1957. The s t a n d a r d i z a t i o n o f Poa annua as an i n d i c a t o r o f smog concentrations. I. E f f e c t s o f t e m p e r a t u r e , p h o t o p e r i o d , and l i g h t i n t e n s i t y d u r i n g growth o f t e s t p l a n t s . Plant P h y s i o l . 32:576-586. K e n d e r , W . J . , and S . G . C a r p e n t e r . 1974. o f g r a p e c u l t i v a r s and s e l e c t i o n s t o F r u i t Var. J . 28:59-61.  Susceptibility oxidant injury.  K o r i t z , H . G . , and F.W. Went. 1952. The p h y s i o l o g i c a l a c t i o n o f smog on p l a n t s I. I n i t i a l growth and transpiration studies. Plant P h y s i o l . 28:50-62. L a n g e , O . L . , R. L o s c h , E . D . S c h u l z e , and L . K a p p e n . 1971. R e s p o n s e s o f s t o m a t a to changes i n h u m i d i t y . Planta 100:76-86. Larsen, R.I. 1971. A m a t h e m a t i c a l model f o r r e l a t i n g a i r q u a l i t y measurements t o a i r q u a l i t y s t a n d a r d s . P u b . No. A P - 8 9 . Environmental P r o t e c t i o n Agency. Lee,  T.T. 1965. Sugar c o n t e n t r e l a t e d t o ozone i n j u r y i n Bot. 43:677-685.  Leone, I.A. plants  and s t o m a t a l w i d t h as tobacco leaves. Can. J .  1976. R e s p o n s e o f p o t a s s i u m d e f i c i e n t tomato to a t m o s p h e r i c o z o n e . Phytopathol. 66:734-736.  Leone, I.A., and E . B r e n n a n . 1969. The i m p o r t a n c e o f m o i s t u r e i n ozone p h y t o t o x i c i t y . Atmos. E n v i r o n . 3:399-406. Levitt, J . 1972. Responses of p l a n t s stresses. Academic P r e s s , N.Y.  to  environmental  L u d w i g , F . L . , W . B . J o h n s o n , R . E . R u f f , and S . B . S i n g h . 1977. I m p o r t a n t f a c t o r s a f f e c t i n g r u r a l ozone c o n c e n t r a t i o n s . p p . 425-438 In I n t e r n a t i o n C o n f e r e n c e on P h o t o c h e m i c a l O x i d a n t P o l l u t i o n and i t s C o n t r o l . Proceedings. Vol. I. E c o l o g i c a l R e s e a r c h S e r i e s , O f f i c e o f R e s e a r c h and Development. E . P . A . - - 600/3- 7 7-0019.  107,  Macdowall, F.D.H. 1965. P r e d i s p o s i t i o n of tobacco t o ozone damage. Can. J . Plant S c i . 45:1-12. M a c d o w a l l , F . D . H . , E . I . Mukammal, and A . F . W . C o l e . 1964. D i r e c t c o r r e l a t i o n o f a i r p o l l u t i n g ozone and tobacco weather f l e c k . Can. J . Plant S c i . 44: 410-417. M a c k n i g h t , M. 1968. i n Pinto bean.  E f f e c t s of PhD t h e s i s .  ozone on s t o m a t a l activity U n i v e r s i t y of Utah.  McCune, D . C , L . H . W e i n s t e i n , D . C M a c L e a n , and J . S . Jacobson. 1967. The c o n c e p t o f h i d d e n i n j u r y i n plants. p p . 33-44 In N . O . B r a d y ( E d . ) Agriculture and the q u a l i t y o f o u r e n v i r o n m e n t . AAAS p u b l i c a t i o n 85. Washington, D.C. Mansfield, T.A. 1973. The r o l e o f the r e s p o n s e s o f p l a n t s to a i r Plant S c i . 2:11-20. Mansfield, T . A . , play a part pollutants?  stomata i n d e t e r m i n i n g pollutants. Comment.  and 0 . M a j e r n i k . 1970. Can s t o m a t a in protecting plants against air E n v i r o n . P o l l u t . 1:149-154.  Menser, H.A. J r . 1962. The e f f e c t s o f ozone and c o n t r o l l e d e n v i r o n m e n t f a c t o r s on f o u r v a r i e t i e s o f t o b a c c o , N i c o t i a n a tabacum L . PhD t h e s i s . U n i v e r s i t y of Maryland. O r i g i n a l not s e e n , a b s t r a c t e d i n Heggestad and H e c k , 1971. Otto,  H . W . , and R . H . D a i n e s . 1969. P l a n t i n j u r y by a i r pollutants: I n f l u e n c e o f h u m i d i t y on s t o m a t a l a p e r t u r e s and p l a n t r e s p o n s e t o o z o n e . Science 163:1209-1210.  P i e r r e , M. 1977. A c t i o n du SO~ s u r l e m e t a b o l i s m e intermediaire. P h y s i o l . Veg. 15:195-205. R e v l e t t , G.H. Ozone f o r e c a s t i n g u s i n g e m p i r i c a l J . A i r P o l l u t . Control Assoc. 28:338-343.  modelling.  Rich,  S . , and N . C T u r n e r . 1972. Importance of on s t o m a t a l b e h a v i o r o f p l a n t s s u b j e c t e d t o J . A i r . P o l l u t . Control Assoc. 22:718-721.  moisture ozone.  Rich,  S . , P . E . Waggoner, and H. T o m l i n s o n . 1970. u p t a k e by b e a n l e a v e s . Science 169:78-80.  Ozone  R i c h a r d s , B . L . , J . T . M i d d l e t o n , and W . B . H e w i t t . 1958. A i r p o l l u t i o n w i t h r e l a t i o n to agronomic c r o p s : V. Oxidant s t i p p l e of grape. Agron. J . 50:559-561.  108  R u n e c k l e s , V . C . 1974. Dosage o f a i r p o l l u t a n t s v e g e t a t i o n . E n v i r o n . C o n s e r v . 1:305-308  and damage  to  S a l t z m a n , B . E . 1954. C o l o r i m e t r i c m i c r o d e t e r m i n a t i o n o f n i t r o g e n d i o x i d e i n the a t m o s p h e r e . A n a l . Chem. 2 6 : 1 9 4 9 - 1 9 5 2 S c h u l z e , E . D . , O . L . L a n g e , V . Buschbom, L . K a p p e n , and M. E v e n a r i . 1972. S t o m a t a l r e s p o n s e o f i n t a c t g r o w i n g p l a n t s t o c h a n g e s i n h u m i d i t y . P l a n t a 108:259-270 Seidman, C , rhythm.  and W . B . R i g g a n . 1968. Nature 217:684-685  Stomatal  movements:  A  S h a u l i s , N . J . , W . J . K e n d e r , C . P r a t t , and W.A. S i n c l a i r . E v i d e n c e f o r i n j u r y by ozone i n New Y o r k v i n e y a r d s . 7:570-572 S t a s i u k , W . N . , and P . E . C o f f e y . 1974. r e l a t i o n s h i p s i n New Y o r k s t a t e . A s s o c . 24:564-568  1972. HortSci.  R u r a l and u r b a n ozone J . A i r P o l l u t . Control  Thomas, M . D . , and R . H . H e n d r i c k . 1956. S e c t . In A i r P o l l u t i o n Handbook. P . L . M a s i l l , C. A c k l e y ( E d s . ) McGraw H i l l , N . Y . Thompson, C . R . , E . photochemical 4:222-224  yearly  9, p p . 1-44 F.R. Holden,  H e n s e l , and G. K a t s . 1969. E f f e c t s o f a i r p o l l u t a n t s on Z i n f a n d e l g r a p e s . H o r t S c i .  Thompson, C . R . , and O . C . T a y l o r . 1969. on g r o w t h , l e a f d r o p , f r u i t d r o p , E n v i r o n . S c i . T e c h n o l . 3:934-940  E f f e c t s of a i r pollutants and y i e l d o f c i t r u s t r e e s .  Ting,  I.P., and IV.M. Dugger J r . 1968. F a c t o r s a f f e c t i n g ozone s e n s i t i v i t y and s u s c e p t i b i l i t y o f c o t t o n p l a n t s . J . A i r P o l l u t . C o n t r o l A s s o c . 18:810-813  Ting,  I.P., and W.M. Dugger J r . 1971. Ozone r e s i s t a n c e p l a n t s . A p o s s i b l e r e l a t i o n s h i p to water b a l a n c e . E n v i r o n . 5:147-150  Ting,  I.P., and R . L . H e a t h . 1975. R e s p o n s e s o f p l a n t s p o l l u t a n t o x i d a n t s . Adv. Agron. 27:89-121  i n tobacco Atmos.  to  air  T i n g e y , D . T . , R . C . F i t e s , and C . W y c l i f f . 1 9 7 3 a . F o l i a r s e n s i t i v i t y o f s o y b e a n s t o ozone as r e l a t e d t o s e v e r a l l e a f parameters. E n v i r o n . P o l l u t . 4:183-192  ••1*0.9  T i n g e y , D . T . , R . A . R e i n e r t , C . W y c l i f f , and W. W. H e c k . 1973b. C h r o n i c ozone o r s u l f u r d i o x i d e e x p o s u r e s , o r b o t h , a f f e c t the e a r l y v e g e t a t i v e growth o f soybean. Can. J . Plant S c i . 53:875-879. T i n g e y , D . T . , W. W. H e c k , and R . A . R e i n e r t . 1971. Effect o f low c o n c e n t r a t i o n s o f ozone and s u l f u r d i o x i d e on f o l i a g e , g r o w t h , and y i e l d o f r a d i s h . J . Amer. Soc. Hort. S c i . 96:369-371. T r e s h o w , M. 1970. Environment McGraw H i l l , N . Y .  and p l a n t  response.  T u r n e r , N . C . , S . R i c h , and H. T o m l i n s o n . 1972. Stomatal c o n d u c t a n c e , f l e c k i n j u r y , and growth o f t o b a c c o c u l t i v a r s v a r y i n g i n ozone t o l e r a n c e . Phytopathol. 62:63-67. V a l l i , V . J . 1971. Ozone damage t o t o b a c c o as a f u n c t i o n of stomatal openings. B u l l . Amer. M e t e o r . S o c . 52:301. W e i n s t e i n , L. 1975. Dose-Response r e l a t i o n s h i p s , pp.Ill s . In W . H . S m i t h and L . S . D o c h i n g e r ( E d s . ) Air P o l l u t i o n and M e t r o p o l i t a n Woody V e g e t a t i o n . Air P o l l u t i o n Working Group. Pinchot Institute . Consortium f o r Environmental F o r e s t r y S t u d i e s . Yale University. PIEFR-PA-1. 1  W i l h o u r , R . G . , and G . E . N e e l y . 1977. Growth o f c o n i f e r s e e d l i n g s to low o z o n e . p p . 635-645 In Intern a t i o n a l C o n f e r e n c e on P h o t o c h e m i c a l O x i d a n t P o l l u t i o n and i t s C o n t r o l . Proceedings. Vol. I. E c o l o g i c a l Research S e r i e s . O f f i c e o f R e s e a r c h and Development. E.P.A.--600/3-77-0019. W i l t o n , A . C , J . J . M u r r a y , H . E . H e g g e s t a d , and F . V . J u s k a . 1972. T o l e r a n c e and s u s c e p t i b i l i t y o f K e n t u c k y b l u e g r a s s (Poa p r a e t e n s i s L . ) c u l t i v a r s to a i r pollution. In t h e f i e l d and i n an ozone c h a m b e r . J". E n v i r o n . Q u a l . 1 : 1 1 2 - 1 1 4 . Zahn,  R. 1970. The e f f e c t on p l a n t s o f a c o m b i n a t i o n sub a c u t e and t o x i c s u l f u r d i o x i d e d o s e s . Staub. Reinhalt. L u f t . 30:20-23.  of  

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