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UBC Theses and Dissertations

Net carbon dioxide exchange rates in Pisum sativum L as influenced by phosphorus and nitrogen nutrition Roelants van Baronaigien, Hendrik Willem Marius 1965

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NET CARBON DIOXIDE EXCHANGE RATES IN PISUM SATIVUM L AS INFLUENCED BY PHOSPHORUS AND NITROGEN NUTRITION  tor  HENDRIK WTT.T.EM MARIUS ROELANTS VAN BARONAIGIEN B.S.A., University of B r i t i s h Columbia, 1 9 5 8  A THESIS SUBMITTED  IN PARTIAL  FUIiFILUJENT OF THE REQUIREMENTS FOR  THE DEGREE OF  MASTER OF SCIENCE IN AGRICULTURE i n the Division of Plant Science  We accept this thesis as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA October 1 ? 6 U  In the  presenting this  requirements  British  mission  I agree  may b e g r a n t e d  without  of this  thesis  my w r i t t e n  i n partial  fulfilment  the L i b r a r y  shall  I further  of this  by t h e Head  agree  that  per-  f o r scholarly  o f my D e p a r t m e n t  I t i s understood for financial  thesis  make i t f r e e l y  that, copying  gain shall  o r by or  n o t be  publiallowed  permissions  ( H . W. M . R. v a n B a r o n a i g i e n ) Department  of  Horticult.urp  The U n i v e r s i t y o f B r i t i s h V a n c o u v e r 8, C a n a d a D  a  t  e  -23 O c t o b e r  1964-  of  degree a t the U n i v e r s i t y of  f o r r e f e r e n c e and study*  representatives.  cation  that  f o r extensive copying  purposes his  f o r an advanced  Columbia,  available  thesis  Columbia,  —  ABSTRACT  Tiro varieties of Pi sum sativum, L, Jade and Olympic, were grown for a period of four weeks from seeding, under constant light intensity and diurnally fluctuating temperatures, while being subjected to varyinga r t i f i c i a l l y induced-degrees of nutrient stress*  Net carbon dioxide exchange  rates were measured i n order to determine the influence of excess or deficient nitrogen and phosphorus concentrations within the nutrient medium. Carbon dioxide assimilation rates, under various degrees of nutrient stress were highly variable, both within the same variety and between varieties tested* Microchemical determinations of chlorophylls a and b, and of inorganic phosphate, nitrate and n i t r i t e were carried out i n order to determine the relationship of some physiological aspects of mineral deficiency to carbon dioxide assimilation* Investigations as to changes i n stomatal index (I) as a result of nutrient stress also showed a large amount of variation* Results obtained indicated that variety Jade was very sensitive to nitrogen deficiency within the rooting medium, as evidenced by a Large increase in stomatal index values with nitrogen deficiency*  Olympic showed a greater sensitivity to phosphorus  deficiency than did Jade* Neither total chlorophyll content, nor chlorophyll a/b ratio appeared to exert any deciding influence upon net carbon d ioxide assimilation* A relationship appeared to exist between CO2  assimilation and quantities of  nitrate and/or n i t r i t e present within the photosynthetic tissues of plants tested* This experiment was unable to f u l l y explain the reason(s) for the great degree of variability of net C0  2  exchange rates extant even between  plant specimens growing i n the same nutrient medium* Same technical improvements applicable to the present experiments as v e i l as some alternative experimental procedures are diseussed*  TABLE OF CONTENTS Page Introduction  1  Review of Literature  2  Materials and Methods  12  A*  Determination o f Net CO2 Exchange Rates  12  B*  Micro-chemical Methods of Analysis  18  Results and Discussion  21  General Discussion  36  Bibliography  38  Appendix  LIST OF FIGURES  Figure 1:  Figure 2«  Carbon dioxide assimilation measurement apparatus  Ik  Inter relationship between nitrogen species and phosphorus i n the plants and net rates of carbon dioxide exchanged - Jade  Figure 3:  28  Analysis of n i t r i t e and nitrate concentration Influence upon net carbon dioxide exchange rates - Jade  Figure U :  2°  Comparison of change i n chlorophyll a and b content i n relation to net carbon dioxide exchange rates - Jade  Figure £j  31  Comparison of the effect of nitrate and n i t r i t e upon carbon dioxide exchange rates and chlorophyll a/b ratio of variety jade  32  LIST OF TABLES Page Maximum and minimum n e t COg exchange r a t e s  Table I s  22  Jade and Olympic  Table l i t  Average stomatal index ( I ) o f v a r i e t i e s Jade  23  and Olympic as modified by mineral composition of n u t r i e n t s o l u t i o n  Table I H t  Summary o f p h y s i c a l l y and chemically determined  25  measurements o f a n a l y s i s - Jade  Table IV:  Summary of p h y s i c a l l y and chemically determined  26  measurements o f a n a l y s i s - Olympic  Appendix Table 1:  I n d i v i d u a l net carbon dioxide exchange rates - Jade  v  Table 2: I n d i v i d u a l net carbon d i o x i d e exchange r a t e s - Olympic  Table 3: A n a l y s i s o f Stomatal Index (I -  S x 100) E + S  1.  IMTRODOCTION  An extensive survey of pertinent literature revealed that, apart from 7/illstatter and Stoil's work(20) with carbon dioxide exchange rate differences between variegated and normal green varieties of the same species of higher plants, l i t t l e i f any investigation has been conducted to determine apparent differences i n carbon dioxide assimilation between normal, ncffwvariegated varieties within any one species of higher plants* Although extensive reports exist concerning the accumulation of inorganic nitrogenous compounds i n the case of phosphorus deficient  plants,  just as carbohydrate quantities are abnormally elevated i n the case of plants growing i n a nitrogen deficient medium, no evidence was discovered concerning a possible explanation of such accumulation. The possibility of the existence of both intra- and intervarietal differences i n carbon dioxide absorption with regard to degrees of sensitivity to nitrogen and/or phosphorus deficiency was explored*  This  thesis presents results obtained during the investigation of the abovementioned aspects of carbon dioxide assimilation by two pea varieties, Jade and Olympic, as affected by varying phosphorus-nitrogen nutrient levels.  2.  REVTEff OF LITERATURE  Literature cited includes various physiological and  biochemical  aspects of both primary and secondary reactions of the photosynthetic process*  Many studies have been undertaken to establish differences i n  carbon dioxide assimilation by plants as measured by quantum efficiency (QE), that i s the number of quanta of the appropriate wavelengths, needed to reduce one molecule of carbon dioxide by various bacteria, algae and flowering plants but no conclusive evidence o£ a basic difference between the organismal quantum efficiencies has so far been found(17)• Investigations relating to differences i n assimilation number (A.N.), a quantity which i s equivalent to the amount of carbon dioxide, measured i n milligram per hour per one milligram of tissue chlorophyll of normal green and (green/white) variegated forms of the same species have shown that for the latter, the assimilation number appears to be s i g n i f i cantly higher i n value than that for the former(20). when the influence of age upon the value of the assimilation number i s studied, the results show that whereas the chlorophyll content of the aging leaf, continues to increase, the rate of photosynthesis also continues to increase, but to a lesser extent(21)•  Studies conducted by  Smillie(l4l) to determine the influence of aging upon photosynthesis  and  respiration showed that age had a detrimental effect upon the photophosphorylating capacity of isolated chloroplasts of pea leaves (lib)*  Smillie(li3)  further demonstrated that the photosynthetic rate per unit of fresh weight at f i r s t rapidly increased, reaching a maximum intensity i n nine-day old leaves, after which i t declined slowly*  On the other hand, i f the  respiration rate of pea leaves was expressed per unit of fresh weight, then  the rate of respiration dropped continuously during the entire aging process* Under the growth conditions employed, leaves were not f u l l y expanded u n t i l they were twelve days old*  The- greatest rates of photosynthesis and  respiration were observed well before leaf expansion ceased* held true for both processes*  This observation  By the time the leaves were f u l l y expanded  (normally at twelve days after germination) both respiration and photosynthesis progressively declined, even i f the chlorophyll content of the maturing leaf continued to increase for a certain length of time (h3)»  In a  continuation of his studies Smillie(lil) examined the respiratory and photosynthetic enzymes and found that the dissimilar patterns for photosynthesis and respiration indicated that the cellular levels of the enzymes involved i n either one of the processes under scrutiny were somewhat divergent from those obtained previously, as follows* Whereas the enzyme involved i n the photoreduction of the triphosphopyridine nucleotide (TFN+-) and ribulose - 1, $ diphosphate carboxylase closely paralleled the results obtained for photosynthesis; the respiratory enzymes, enolase, 6—phosphogluconic dehydrogenase and aconitase showed an i n i t i a l high value, at the leaf>s very early stage of development, but dropped soon after at a very rapid rate*  In the case of the  enzyme, transketolase, a catalyst, hot only involved i n respiration, but also i n the reformation of the carbon dioxide acceptor, Smillia(UL) found that the activity changes shown by this enzyme, up to the ninth day of development could be interpreted as being the net result of an increased action of the enzyme i n regard to i t s association with photosynthesis rather than i n i t s role as a respiratory enzyme*  The most pronounced deviation from the photo-  synthetic activity of this enzyme was found i n the youngest leaves where the transketolase i s apparently mainly active as a respiratory enzyme and that consequently this enzyme i n this instance parallels the degree of activity of the other respiratory enzymes, previously mentioned*  k.  Smillie and Krotkov(43) working with the pea variety Laxton's Progress, determined both biochemical and physiological changes occurring in developing pea leaves. They found that the moisture content of young developing leaves increased from 82.8 percent to 87.1 percent of the total weight.  The number of cells per unit area decreased more rapidly than the  dry weight, thus suggesting that c e l l expansion involves not only synthesis of new cellular materials but increased uptake of water as well.  The fresh  weight increase of the leaves continued u n t i l they had reached the age of twelve days, by which time a l l had f u l l y expanded. At sixteen days after germination these workers noted that leaf fresh weight had diminished slightly.  Determination of protein content during the leaves* period of  development revealed the existence of a general tendency to decrease with age.  This phenomenon is also known to occur i n tobacco(52) and sugar cane(32)  as determined by measurement of total nitrogen content. Differences i n protein content during the maturation process in leaves has been interpreted by Smillie and Krotkov(h3) as being indicative of a net change i n the level of enzyme systems involved i n a number of different metabolic pathways. In support of this hypothesis they cite the discovery of Smillie and Fuller(U2) that concentration levels of a certain group of glycolytic enzymes as a function of leaf age, were considerably different from a number of enzymes participating almost solely i n the process of photosynthesis. Changes i n chlorophyll content, expressed on a leaf fresh weight basis were noted; this pigment increased rapidly from an i n i t i a l low to a peak at the age of thirteen to fifteen days, after which the total chlorophyll content of the leaves slowly decreased.  Nucleic acid  determination of leaves during the various stages of development, revealed a  5. continuous decline as the leaves approached f u l l maturity; the ribonucleic acid declined at a faster rate than the desaxyribonucleic acid*  Study of  changes i n ribonucleic acid content of individual leaves, resulted i n the discovery that this compound increased up to three days after germination, after which period i t declined quite rapidly* Curtis and Clark(10) state that because nitrogen i s a normal and essential constituent of chlorophyll, a low nitrogen concentration should be conducive to a low chlorophyll content i n the plant. The same authors continue with the observation that even with no actual reduction i n the total quantity of nitrogen within the leaf, an abundance of carbohydrates present within the leaf, may actually decrease the amount of nitrogen available for chlorophyll synthesis, due to the fact that high carbohydrate levels favour amino-acid synthesis - other than glycine - the precursor of the porphyrin ring of chlorophyll* Meyer and Anderson (30) declare that any environmental factor - such as high-light intensity, low temperature or low nitrogen favouring an accumulation of carbohydrates i n a given plant tissue, often causes anthocyanin formation i n that tissue, provided, of course, that the necessary genes for the formation of such pigments are part of the tested individual's inheritance. Eckerson(13) noted that i n the absence of phosphorus the protoplasm of young cells became less refractive and that the chloroplasts disintegrated f i r s t i n the stem, and lower leaves and f i n a l l y i n the upper ones*  She also  demonstrated that synthesis of proteins did not occur at the usual rate i n phosphorus deficient plants* Experiments conducted by Aronoff et a l ( U ) revealed that the aminoacids alanine and aspartic acid, as well as malic acid, were slowly labeled i n the dark when algae were exposed to labeled carbon dioxide*  However, the  aforementioned compounds were labeled much more rapidly i f the algae were  actively photosynthesising just prior to the moment of the addition of the labeled carbon dioxide* Nichiporovich(33) has presented evidence that synthesis of proteins i n the chloroplasts of higher plants was greatly accelerated during photosynthesis*  The accelerated protein formation appears to take place directly  from the intermediates of photosynthetic carbon dioxide reduction since the proteins were labeled when labeled carbon dioxide (C^U) was used, but NOT when labeled carbohydrates (C ^) were administered* 1  Brachet et al(£),  endeavouring to determine the effect of photo-phosphorylation upon protein synthesis found that labeled (Clii) glycine was incorporated into the microsomal fraction of Acetobularia proteins, at rates which were independent of the influence of light*  However, i f labeled carbon dioxide was fed to  Acetobularia, the labeled carbon was soon incorporated into the chloroplasts' proteins* Meyer and Anderson(31), discussing the relative quantities of pigments present i n chloroplasts of higher plants, state that the ratio of chlorophyll a to chlorophyll b i s approximately three*  They also declare  that the proportion of chlorophyll a to that of b i s higher i n "shade leaves of many plants, than that of "sun leaves" of the same species*  This state-  ment i s substantiated by Fruton and Simmonds (lf>) * Schertz(UO) showed that the factors influencing the quantity of chloroplast pigments are r a i n f a l l , s o i l moisture, nutrient levels i n the culture medium, light intensity, temperature and humidity*  Sprague and  Shive(U5) working with corn, concluded that the chlorophyll content of a plant i s more closely correlated with leaf area than with dry weight of leaves* Reed's(38) work revealed that where phosphorus i s withheld from plants, the formation of phosphatides i s severely inhibited while the  0  synthesis of triglycerides reaches abnormal proportions* Kamen(23) cites that chemical analysis of chloroplasts shows them to contain as much as forty percent of total dry weight i n phospholipids* In this respect they resemble the mitochondria(27)*  In Scarlet Runner bean  chloroplasts six phosphatides were found, five of which have been identified as lecithin, phosphatidyl ethanolamine, phosphatidyl glycerol, phosphatidyl inositol and phosphatidic acid* Kamen(23) also reported that the enzyme lecithinase, the agent responsible for the degradation of lecithin, i s concentrated i n the chloroplastic fraction of the leaf*  Garolus(d) working with cowpeas and tomatoes,  grown under greenhouse conditions, showed that absence of nitrogen increases the inorganic phosphate content of c e l l sap from forty-four to one thousand forty parts per million*  Nightingale(3U) discovered that i n general the  absorption of inorganic nitrogen was depressed when phosphorus was present i n adequate or high concentrations i n the nutrient medium* Walter (1*6) immersed plants of the water weed Anacharis canadensis Rich et Mich* i n various concentrations of sucrose solutions and studied the effect of this treatment upon the rate of photosynthesis. He found that the greater the concentration of the sucrose solution the less the tuxgiidity of the cells, the less the hydration of protoplasm, and the lower the rate of photosynthesis*  In one experiment the rate of photosynthesis was appreciably  retarded by immersion of the plants i n a 0*3 molal solution and almost entirely stopped i n a 0*7 molal solution of sucrose with an osmotic pressure of approximately eighteen atmospheres*  However, the rate of respiration was  practically unaffected by sucrose solution at any concentration up to and including a 1*0 molal solution* Pleasants(36) noted that the stomata of plants with abundant nitrogen present, opened more widely i n the case of adequate levels of moisture, while  8. they closed more promptly and completely when the water supply to the plant became limited* Ziegenspeck(U8) found that i n a given leaf the stomata do not appear to be formed a l l at once; on the contrary such formation occurs during a. considerable period of time*  He was able to demonstrate the fact that two  principal developmental patterns are to be distinguished:  (a) i n leaves  with parallel veins where the stomata are arranged i n longitudinal rows, the different stages of the stomata! maturation process are observable i n successively more highly differentiated parts of the leaf; the distribution of these stages following a baslpetal sequence, and (b) i n leaves of netted venation*  In this case, stomata of varying degrees of maturity are distributed  i n a much more random fashion, mature stomata being found side by side with those s t i l l i n their i n i t i a l stages of development* Salisbury(39) while conducting an extensive investigation into the stomatal frequency of the woodland flora i n England, discovered the existence of a high positive correlation between the number of stomata and the number of epidermal c e l l s per unit of leaf area*  Differences i n stomatal frequency  found, are due to the spacing of the stomata, and not to the differences i n the number of stomata formed per number of epidermal cells per unit area* Salisbury(39) then proposed a quantity which he named the stomatal index and which serves as an expression of the percentage proportion of the ultimate divisions of the leaf dermatogen that has been converted into stomata* Therefore a species under a given set of conditions w i l l try to adjust to these conditions by forming a definite proportion of stomatal i n i t i a l s * Salisbury(39) concludes with the statement that variations i n the value of stomatal indices obtained, may be due entirely to internal changes within the plant, even i f these changes are caused by external factors of which nutritional variability i s possibly the most important one*  Experiments by Burstrom(67) on the reduction of nitrate i n the leaves of young wheat plants indicate that the process i s closely linked with the simultaneous reduction of carbon dioxide i n the photosynthetic process, and that light i s the source of energy. No reduction of nitrate was found to take place i n wheat leaves i n the dark, even when conditions appeared favourable for the process.  Respiratory energy was not utilised  i n this mechanism* Eckerson(ll) followed some of the steps i n the reduction of nitrate i n the tomato plant* Young plants were transplanted to quartz sand and watered with nutrient solution lacking nitrogen compounds u n t i l such time that micro-chemical tests were negative for nitrate, n i t r i t e , ammonia and free amino acids, while carbohydrates were s t i l l present i n great abundance* Calcium nitrate was then added to the sand* The nitrate ions were rapidly absorbed and could be detected i n a l l parts of the plant within twenty-four hours after the f i r s t administration*  In thirty-six hours nitrites were  present i n considerable amounts at the tips of the stems and i n other tissues* Traces of ammonia could also be detected*  By the end of forty-eight hours  the quantity of nitrite had decreased, the amount of ammonium ion had increased and a small amount of asparagine was also present* amino acid synthesis proceeded normally*  Subsequently  Quantitative measurements estab-  lished that during amino acid synthesis the carbohydrate content of the c e l l decreased significantly* Hageman and Flesher(l8) demonstrated that nitrate ion concentration levels of *015> M* or more inhibit the process of photo-reduction of t r i phosphopyridine nucleotide (TPN-f-)*  Their findings confirmed the previous  report by Evans and Nason ( I U ) who discovered that nitrate ion concentrations of *02 M. although optimum for nitrate reductase activity, proved sufficiently detrimental to the photo-reduction process of triphosphopyridine nucleotide  10»  (TPN) to cause a seventy-five percent reduction of the photo-reductive rate i n plants grown at lower nitrate ion concentration levels present i n the nutrient solution* These workers also found that reduction of nitrite was inhibited " i n vitro" by the presence of hydroxylamine hydrochloride (NH2OH.HCI) at 1X>~3 molar concentrations within the reaction mixture* Hageman and Flesher(l8) also discovered that the enzyme, nitrate reductase, fluctuated with both the amount of light to which the plant i s exposed, and the concentration of the nitrate ion present i n the plant* The inhibitory effect of nitrate ion concentrations upon photo-reduction of triphosphopyridine nucleotide has been explained by Lundegardh(2f>), through his discovery that leaves of nitrogen deficient oat plants were much more active photosyntheticaUy  than leaves of plant controls, grown on media i n  which adequate amounts of nitrate were present* Kraybill(2i*), studying the interaction of nitrogen and phosphorus i n plants, discovered that inorganic nitrates were not reduced by tomato plants i n the absence of phosphorus, an interesting observation i n the light of the findings by Evans and Nason (lit) who established that the photoreduction of triphosphopyridine nucleotide (TPN) i s conducive to nitrate reduction i n plants, but only i n the absence of gaseous oxygen; the latter observation i s doubtless due to the fact that the nitrate ion can serve as a hydrogen acceptor instead of molecular oxygen*  This process i s accompanied  by the formation of three, high-energy adenosine triphosphate molecules per one nitrate ion reduction [N (V-plus) to N (HI plus)] for n i t r i t e i n a manner comparable to "respiratory chain* phosphorylation* Concerning the effect of molecular oxygen upon nitrate photoreduction, McAlister and Myers (26) showed that the rate of photosynthesis i n young wheat plants was about thirty to f i f t y percent higher i n one half per cent oxygen than i n twenty percent oxygen at high light intensity and at  11. atmospheric carbon dioxide levels of concentration*  Eckerson(12.) noted that  depletion of phosphates i n tomato plants, caused a very rapid decrease i n nitrate reducing substances i n succession i n leaves, stems and roots, while inorganic nitrates accumulated i n the same sequence.  MacGillivray(29)  established that tomato plants growing i n a phosphorus deficient medium, contained more total nitrogen than those grown i n complete nutrient media. He also discovered that the stems of phosphate starved plants contained  three  times as much water soluble nitrogen and four times as much nitrate ammonia and urea as well as cf-amino acid nitrogen as the stems of the controls grown i n complete nutrient media*  These findings were confirmed by Hanmer(19).  McCool and Weldon(28) showed conclusively that the phosphate content of plant sap i s decreased by application of sodium nitrate* Anderson and 6athurst(2) demonstrated that excess nitrate within the growth medium reduces the amount of inorganic phosphate absorbed by the plant root. Anion et al(3), Allen et al(l) and Whatley et al(ltf) discovered that chloroplasts, obtained through fractional uibra-centrifugation from c e l l material did not possess any aerobic oxidative metabolism i n the absence of light*  In other words the chloroplasts did not respire.  12  MATERIALS AND METHODS  A*  Determination of Net Carbon Dioxide Exchange  Seeds of Pisum sativum (L.) varieties Olympic and Jade, treated with Spergon, were planted i n clean, one-gallon plastic containers; twelve seeds were sown i n each pot, and vermiculite (Horticultural Grade TerraLite, Grant Industry Ltd., Vancouver, B.C.)  served as the rooting medium.  After planting of the seeds each pot received sufficient d i s t i l l e d water (generally lf?00 ml per pot) to saturate the originally dry rooting medium* Pots thus prepared were placed i n a controlled growth chamber (Percival, Boone, Iowa), at a photo period of sixteen hours per twenty-four; day temperature was maintained as close to 19»k° C as possible and night temperatures varied between lh and U>° G*  Light intensity was maintained  at a constant level of about 3000 foot candles, as determined with a Weston Model 756 Illumination Meter* During the f i r s t week of the plants' development i n the growth chamber, the seedlings received sufficient water to maintain the saturation level of the vermiculite rooting medium* At the end of the f i r s t week, plants were thinned to seven uniformly developed plants per pot; cotyledons were removed by excision and upon completion of this operation, each pot was watered with five hundred ml of the appropriate nutrient solution; whose solute composition was based upon the Hoagland nutrient solution modified by the addition of FeEDTA and varied by adding or subtracting nitrate nitrogen and/or inorganic phosphate as follows:  13. Treatment  Number o f Sets  Concentration N/lQOO m l  +P  h  1|2 ppm*  N - P  k  k2 ppm*  P - N  h  N  o  Concentration P/lOOO m l  35 ppm. 0  35 ppm. i.  W*  1  21 ppm*  17.5 ppm.  2N2P  1  8ii ppm*  70 ppm*  |N - P  1  21*0 ppm*  |P - N  1  2N - P  1  81* ppm*  2P - N  1  0 ppm*  70 ppm*  -P - N  1  0 ppm*  0 ppm.  0  0  17*5 ppm. 0  Each pot received f i v e hundred ml.of the appropriate n u t r i e n t s o l u t i o n twice per week u n t i l f o u r weeks from the date o f p l a n t i n g . I n a d d i t i o n t o the n u t r i e n t s o l u t i o n treatment, p l a n t s received s u f f i c i e n t d i s t i l l e d water throughout the period t o maintain a constant water l e v e l i n the b a s i n l o c a t e d beneath each pot. A f t e r the f o u r week period o f development had elapsed each i n d i v i d u a l : p l a n t was i n s e r t e d i n t o a c l e a r p l a s t i c chamber o f i n n e r dimensions 1U.6 cm by  30*2 cm by 1**2 cm ( t o t a l volume o f 1852 ml) f o r a period o f t e n t o f i f t e e n minutes, depending upon the speed w i t h which the i n d i v i d u a l p l a n t achieved the steady s t a t e o f carbon d i o x i d e a s s i m i l a t i o n * The a i r from the p l a s t i c carbon dioxide exchange chamber was drawn by a small e l e c t r i c pump and fed i n t o a Beckman Model ISA i n f r a - r e d gas analyser, connected t o an a m p l i f i e r and recorder*  An open system was main-  tained throughout the experiment i n order t o maintain as c l o s e l y as p o s s i b l e the environmental c o n d i t i o n s , under which these p l a n t s had been growing during t h e i r f o u r weeks period of. development*  The scheme f o r i n d i v i d u a l carbon  d i o x i d e absorption a n a l y s i s i s presented i n f i g u r e 1*  FANS FOR CIRCULATION OF AIR & TEMPERATURE CONTROL LIGHT SOURCE  i - i  Electric Fa Chamber  Thermograph  Amplifier  FIGURE  1.  Recorder  CARBON DIOXIDE ASSIMILATION MEASUREMENT APPARATUS  15. Carbon dioxide exchange as measured by absorption or evolution i n the plastic exchange chamber was calculated as milligrams of carbon dioxide per l i t e r of a i r per one hour, per one square decimeter of leaf area per plant, i n accordance with the following formula:  1,9769 x 7.98* x 273 x Xppm/1000 TI Leaf Area i n dm? For the purpose of this experiment the quantity ^ 2  has been discarded i n  favour of the constant .9 (equivalent to £Z2) due to the fact that the  295 temperature within the plastic carbon dioxide exchange chamber was very nearly constant throughout the entire period of measurement (varying from  22*0° C to 23.5° C). The value of X i n the above formula was experimental l y determined by observing the difference between the carbon dioxide content of the a i r i n the exchange chamber (measured through intake A of the Figure 1) i n the presence of the individual plant, tested and that of the a i r i n the growth chamber (intake B of Figure  1).  The recorder quickly indicated any change i n carbon dioxide levels of the plastic chamber i n the presence of the plant. Two separate measurements were taken for each plant i n order to ensure that any possible stimulatory effect upon respiration, due to mechanical handling (21) would be minimal* The Beckman Model l£A infra-red gas analyser was zeroed by leading pure gaseous nitrogen into the instrument (commercial grade nitrogen was used from which possible carbon dioxide had been eliminated by forcing the gas through limewater, prior to introducing i t into the instrument) just prior * The value 7.98 i s derived from 60 x 133A°° G where 133 i s the flow rate per minute i n m i l l i l i t e r s ; and 60 i s sixty minutes * 1 hour* The value 1*9769 stands for the weight i n grams of one l i t e r carbon dioxide at 0° C and standard pressure*  16. to commencement of carbon dioxide analysis. The flow rate of a i r was regularly checked, by attaching intake B (of Figure 1) to a plastic hose, connected to the top of a one hundred ml pipette containing a few drops of detergent solution.  Partial opening of  the stop cock at the lower end of the pipette, caused a film of detergent to be formed.  The time required for this film to travel the one hundred ml  volume of the graduated pipette was determined with the aid of a stopwatch (1)5.06 seconds). The time value thus obtained was used to determine the flow rate per one minute time period. Prior to the commencement of each series of carbon dioxide exchange analyses, the flow rate of the a i r through the system was determined and, i f required, readjusted to the previously maintained value of one hundred thirtythree ml per minute.  This ensured greater ease of calculations and maintained  the calculated equivalent of one ppm on the recorder as a constant. After completion of each plant analysis, the a i r i n the growth chamber was analyzed for carbon dioxide content via intake B, with the a i d of a tridirectional stop cock, as indicated i n Figure 1. Assuming the carbon dioxide content of the a i r i n the growth chamber to be equal to 0.03 percent, i t was noted that f i f t y units of the recorder graph paper each represented an amount of six ppm of carbon dioxide. During the course of these analyses, i t was found necessary to occasionally use a different unit measure, i n order to determine more accurately the sometimes minute quantities of C O 2 exchanged by the plants. After completion of each analysis of the individual specimen the t o t a l leaf area having been actively involved i n the carbon dioxide exchange analysis was determined as follows. A l l leaves and bracts included i n the exchange chamber were detached from the stems and spread upon a pane of glass. On top of these leaves a light sensitive ozalid paper was placed and held  firmly to the glass pane* The package was then exposed to a light source from a 200-watt bulb for approximately ten minutes*  When the light source  was removed, the ozalid paper was then subjected to the action of ammonium hydroxide vapour i n a stoppered glass cylinder to allow colour development* The resulting purple leaf images represented total leaf area of the plant* The area of these images was determined with a planimeter and the total number of square inches of leaf area (planimeter units of measure) converted to sq*dm* through multiplication by the factor of conversion: 6*1J52* A l l leaves belonging to one particular set and treatment were gathered and dried at 100° C for micro-chemical analysis for inorganic phosphate, nitrate and n i t r i t e content, as well as total chlorophyll a and b. Carbon dioxide quantities absorbed were expressed as amounts of this gas both per one gram of dry weight and per one gram of total, chlorophyll*  Values thus obtained were used to determine the possible existence  of both intra- and inter-varietal differences i n the varieties Jade and Olympic examined i n this experiment* Stomata counts were made of both upper and lower leaf surface to determine the possible difference i n numbers of stomata and/or their distribution between the two pea varieties studied* Leaf surface impressions were made by painting the upper and lower sides of each leaf with nail polish*  When dry, the transparent film was removed and stomata impressions  counted under X30 magnification (per predetermined area of *00035mm?)* Stomatal indices were taken of each treatment and compared for possible differences due to the influence of nutrient levels, i n accordance with the procedure of Salisbury (6$)»  18. B*  Micro-chemical Methods of Analysis Dried Pea Leaf Tissues*  Preparation of Tissues for Analysis A l l samples were oven-dried at 100° C to constant weight. After removal from the oven each sample was weighed, then ground i n an agate mortar (four inch diameter) with ca.0.1 gram calcium carbonate added(9)* After the tissue was thoroughly disintegrated, a l i t t l e 85 percent reagent grade acetone was added and grinding continued*  The extract was  then filtered through a Buchner funnel, fitted with low ash Watman No. 50 f i l t e r paper*  The residue was washed again with solution of 85 : 15 acetone  water. This procedure was continued u n t i l the tissue residue appeared colourless. The f i l t r a t e s were transferred to 100 ml graduated flasks and made up to the mark with the above mentioned solvent mixture* Aliquots of f i f t y ml were pipetted into separatory funnels containing f i f t y ml of petrol ether*  D i s t i l l e d water was carefully added u n t i l i t  became apparent that a l l fat soluble pigments had entered the ether layer* Upon draining off the ether layer, the remaining H 2 O layer was saved for further analysis* The separatory funnel containing the ether solution was placed i n the upper rack of support* Approximately 100 ml of water was introduced into a second separatory funnel and placed i n the supporting rack below the ether containing funnels* The ether solution was allowed to run into the lower funnel* When * Analyses were carried out by Mr. W. Sargeant, of the firm of Coast ELdridge, Engineers and Chemists Ltd*, Vancouver, under the Author's supervision*  a l l solution had l e f t the upper separatory funnel, the latter was rinsed with a l i t t l e ether*  Reversing the position of the two funnels, the funnel  containing both the water and ether solutions was drained and the water layers saved* These procedures were repeated 10 times u n t i l a l l acetone was removed* The ether solutions were introduced into 100 ml volumetric flasks and made up to volume*  Sixty ml reagent bottles, into which some anhydrous  sodium sulphate had been introduced, were f i l l e d with ether solutions containing extracted chlorophyll pigments* When the solutions were optically clear, aliquots were pipetted into another dry bottle and diluted with enough dry ether to cause the value of logj, I o / l to be between 0*2 and 0*8 at wavelength 660  m/u.  Aliquots were transferred to absorption cells and readings taken of Io and I at 660*0 m/u and 61*2*5 m/u,  using a DK2 Beckman Spectro-photometer*  Quantities of chlorophylls a and b were calculated i n accordance with the following formulae:  Chlorophyll a (mg/liter)  a  9*93 log 1° (660)  - .777 log ISL ,,  x  I  Chlorophyll b (mg/liter) = 17.6  log 1°. (6^2.5) "  2 , 8 1  lo  S  0  d  .  I  (OU2.5;  —  (660)  After drying, the extracted plant residues were transferred to beakers, using d i s t i l l e d water and the mixtures were digested at 20 degrees C for four hours with constant shaking, to extract the inorganic water soluble salts*  The residue was filtered through a Buchner funnel, using a  low ash f i l t e r paper, and the supernatant liquid added to the previously collected water layers, saved during the process of the chlorophyll extraction. Combined extracts were made up to constant volume and aliquots used for phosphate, n i t r i t e and nitrate determinations*  20. Inorganic Phosphate  determination(35>)  The inorganic phosphate content of each sample was determined photo-coloilmetrically i n accordance with method number 2 of the Publication Number 106U of the Research Branch of the Department of Agriculture, Chemical Methods of Plant Analysis, with some modifications to conform with micro-analytical requirements* Colour developing reagents were prepared as follows: Reagent I*  Ammonium molybdate - 6.6 percent solution  Reagent III.  Five grams of ferrous sulphate are dissolved i n f i f t y ml of d i s t i l l e d water and after disolution was complete, one ml of 7*5 N H S0^ i s added. 2  Reagent ILT was freshly prepared every two hours. Readings were taken at 700 m^U, using a Number 66 Red f i l t e r . Quantities of inorganic phosphate present were expressed as ^grams Pi per one gram dryweight of leaf tissue per average plant per set. Nitrite Nitrogen determination(37) Nitrite nitrogen was determined i n accordance with method D:2£c diazotization method - of Methods of Collection and Analysis of water samples of the Geological survey of water supply paper IkBh (I960) • Nitrate Nitrogen(37) A fresh sample of the original extracts was heated with hydrogen peroxide, to oxidize n i t r i t e to nitrate.  Nitrate nitrogen was then determined  in accordance with method D25>.b.l using phenoldisulphonic acid* Differences between the former and the latter quantities represents nitrate nitrogen present i n the sample. nitrate nitrogen are reported i n per plant per set.  Quantities f o r both n i t r i t e and  grams per one gram dry weight of leaves  21  RESULTS AM) DISCUSSION  Carbon dioxide exchange rates, experimentally determined showed pronounced variability amongst plants subjected to the same nutrient treatment (Table 1)* The other specimens belonging to individual sets absorbed carbon dioxide i n quantities somewhere i n between the maximum and minimum values shown* This was found to be true for individuals belonging to both the Jade and Olympic varieties* When the average values of stomatal indices for both upper and lower leaf surface areas of the two pea varieties were determined i n accordance with Salisbury's procedures (65) the following was noted* Whereas the stomatal indices (I) f o r the upper leaf surface areas of both varieties studied did undergo a certain change i n value (Table n), those for the lower leaf areas exhibited a much more pronounced change from the pattern on the upper surface as follows*  Although both Jade and Olympic appeared sufficiently  sensitive to phosphorus deficiency i n the nutrient medium to show a slight change i n stomatal index values, the variety Olympic exhibited a markedly greater tolerance to nitrogen deficiency than Jade*  The l a t t e r appeared  highly intolerant to a lack of this mineral as was indicated by an increase of the original stomatal index value at 2ii.O to 31*. 9 an equivalent of f i f t y eight percent*  Olympic was only slightly more sensitive to phosphorus  deficiency than was Jade*  These results were borne out by the finding  that Olympic nearly always showed symptoms of phosphorus deficiency (such as stunting, accompanied by great reduction i n intemodal distances, brittleness of leaves) more frequently and much earlier during i t s development than Jade when grown under identical conditions. When amounts of net carbon dioxide exchanged by specimens of either variety were expressed as milligrams of CO2 per gram of dry weight of leaf  T A BLE  I:  JADE Variety Treatmt. JADE  N + P  N -P  P -N  22  MAXIMUM AND MINIMUM NET CARBONDIOXIDE EXCHANGE RATES FOR VARIETIES  OLYMPIC Set  Plants per set  M R COo Min.  Max.  Variety rreatmt.  Plant! per set  1  5  .60  .28  2  1  7  1.0  .45  2.  6  .71  .35  2  6  .94  .40  3  6  .80  .52  3  6  .63  .36  4  7  .71  .34  4  5  1.06  .39  1  7  .31  .09  1  6  .26  .11  2  6  .42  .24  2  6  .66  .19  3  5  .45  .13  3  6  1.05  .23  4  6  .71  .24  4  6  .05  .27  1  6  1.71  .63  1  6  .94  .43  2  4  .80  - . 18  2  4  .31  -.96  3  4  .71  .15  3  4  .78  .59  4  6  .84  .29  4  3  .36  -.07  4a  3  OLYMPIC  N+P  Mg C 0 Min. Max.  Set  N -P  P -N  Compensat ion Point  -(N+P)  1  6:  .46  .15  1/2(N+P)  1  6  .55  .36  -(N+P)  1  5  .72  . 35  2(N+P)  1  5  .60  .40  1/2(N+P)  1  5  .59  .36  2(N+P)  1  4  .63  .49  1/2 P-N  1  4  .78  .38  2 P-N  1  4  .45  .21  1/2N-P  1  5  .78  .33  2N-P  1  4  .62  .33  1/2P-N  1  6  .67  .36  2P-N  1  5  .45  .11  1/2N-P  1  6  ,78  .52  2N-P  1  4  .64  .58  23 TABLE  Variety  JADE  Treatmt.  II:  AVERAGE STOMATAL INDEX OF VARIETIES JADE AND OLYMPIC AS MODIFIED BY MINERAL COMPOSITION OF NUTRIENT SOLUTION  AVERAGE I Dorsal Ventral  Variety  Treatmt.  AVERAGE I Dorsal Ventral  N + P  17.1  23.5  28.0  N - P  20.6  29.1  34.9  P - N  22.1  26.6  N + P  21.7  24.0  N - P  22.7  P - N  25.4  OLYMPIC  a* tissue and then compared (Tables i n and IV), the resultant values revealed that Jade variety, while much more vigourous i n physical appearance, was apparently less able to absorb carbon dioxide under adverse nutritional conditions than Olympic, An exception was the l a t t e r s behaviour i n 1  relation to carbon dioxide exchanged, when grown i n nitrogen deficient nutrient media containing s tandard quantities of phosphorus, A further observation was that from a total of sixteen experimental sets of Jade, four showed a pronounced deficiency of nitrate N (V plus) within their tissues (Tables III and IV),  % e n these sets were  compared with respect to net carbon dioxide uptake, i t became apparent that i n the absence of phosphorus within the nutrient medium the quantities of carbon dioxide assimilated by plants grown i n complete Hoagland solution < (i.e. Jade Table III - sets 2 and 3 for (N + P) - and set 2 of N - P) treatments)* were slightly higher for the latter treatment. In the case of Jade plants (Table i n ) grown i n twice the normal amount of phosphorus, but lacking an EXTERNAL source of nitrate i t was interesting to note that the n i t r i t e N (III plus) was found to be present i n plants, i n sufficient quantities to be determined micro-chemical l y and i n amounts equal to one half the quantity found i n plants grown i n nutrient media, deficient i n nitrate (N (V plus) but containing standard  concentra-  tions of phosphorus. This observation did not hold true for the Olympic variety (Table IV) for which i t was found that the nitrate content of those plants (grown i n (P - N) media) which had reached the Compensation Point, was approximately equal to twice the amount of nitrate i n those plants, whose net carbon dioxide exchange rates had reached values lying above the compensation point.  TABLE  IH':.  SUMMARY OF PHYSICAL AND CHEMICALLY DETERMINED MEASUREMENTS OF ANALYSIS J A D E  CO2X10-4 Total. Average No. Average Mg per Treat- M g C 0 D. Wt. Dry Wt. of Plant SET ment D M Leaf Mg Plants IMG D. W. 2  2  M g Chlorophyll Ratio Mg Pi M g C02 Average Average Average /Plant/GR A +N + MgPi Mg N°+ Mg N 3 + Drv Weight B Plant /Plant A B IG D. W. /Plant /Plant 3  Mg Pi Total Chlorophyll Mg P« +N3+ GR C O 2 Chlorophyll " +N5+ +N5+ Plant Plant Plant GR Chi Plant DW D. W.-  -  .545  .55  1. 31  .541  .54  - •  .71  . 770  .77  -  -  .50  .571  .57  -  2. 3  -  .35  .754  .75  145 3.9  -  1.09  -  .64  . 652  .65  .305  177  1.7  .80  .62  .92  .42  .482  .48  1.7  .497  172 2.9  2. 80  1. 67  3, 37  .56  .669  .67  0  .293  095 3.0  1.29  . 388  .39  5.4  .54  .23  0  .97  .405  14  3.7  1.20  1221  7  5,8  .58  .64  0  .54  .421  12  3.5  1.18  2673  534  5  10.3  1.03  .95  .92  0  .600  17  3.5  -  1.87  . 3228  3013  502  6  6.4  .64  .18  0  l»-4  .436  135 3.2  1.58  3  . 2401  1270  254  5  9.4  .94  .30  2.0  0  .576  178 3.2  4  .4563  2110  351  6  12.9  1.29  .26  .81 .  0  .507  . .2068  959  239  4  8.6  .86  .50  .12  .3  3  .4073  1826  456  4  8.9  .80  1.10  .57  4  .5007  1829  304  6  16.4  1.64  .50  5526  921  3  . 7115  8549  4  . 5502  2  2  N+P  N«P  P-N  1.4  li-90  -  1  1/2P^  .5317  2126  354  6  15.0  1.50  .25  .75  0  .218  070 3.1  1  2P-N  .2407  2715  543  5  4.4  .44  .40  0  .8  .234  , 208 1.1  1  1/2N-F  .6319  3268  544  6  11.6  1.16  .15  1.0  0  .348  141 2.4  1  2N-P  . 6044  2379  594  4  10.1  1.01  0  1.6  0  . 925  192 4.9  -  1  - -.N-P  .3637  4390  731  6  4.9  .49  .36  .35  .23  .386  105 3.6  .59  1  1/2N 1/2P  .4639  4319  719  6  6.4  .64  .15  .15  .81  360  151 2.3  .96  2N2P  . 4992  4410  882  5  5.6  .56  .26  .28  .46  .740  154 4.9  .72  1  -  .97  6  . 5019  2  1.20  1.00  -  1. 84  .288  .29  -  -  .54  .442  .44  -  1.29  .489  .49  .54  1.117  1.12  .94  .74  .491  .49  .30  1.11  .90  .511  .51  .54  1.00  .56  .894  .89  1.15 1.6-P  TABLE IV:  Average Treat- Ma C02 SET ment D M * Leaf  SUMMARY OF PHYSICALLY AND CHEMICALLY DETERMINED MEASUREMENTS OF ANALYSIS  CO xl0-4 Total Average No. Average Average Average MgChlorophyll D. Wt. Dry wt. of M g Pi Mg N * Mg N~+ /Plant/GR D . W. Mg per Mg C 0 Mg Plant Plants IMg D , W, IG D . W. /plant /Plant /Plant a b 3  2  .5932  3935  655  6  9.0  .90  .50  .61  3  .4681  3761  626  6  7.4  .74  .76  .95  4  .6595  1540  308  5  21,4  2.14  1.10  .3804  2535  422  6  6.0  .90  3  .5059  2430  405  6  12.4  1.24  4  .4839  2212  368  6  13.1  -.3671  1220  305  4  -12.0  3  .6755  995  248  4  4  .3428  1260  420  2  2  2  N+P  N-P  P-N  «  M s Pi Total +N3+ GR C 0 ChlorMgJ>i Mg. Pi +N +N ophyll Plant Plant Plant Plant GR Chl. Plant DW 2  2  Ratio a/b  5+  J+  .372  .101  3.5  1.11  -  0  .555  .160  3,4  1.71  1. 38  0  .620  .178  3.4  .60  .86  0  .460  .115  .15  .86  0  .460  .16  1.11  0  -1.20  1.17  2. 35  27.2  2.72  .60  3  8.2  .82  1. 31  Chlorophyll D . W.  -•  1.25  .473  .47  -  -  ..64  .715  .72  2.48  -  -  .82  .798  .80  4.0  1.46  -  -  .93  «5*75  .58  .125  3.6  1. 01  -  -  ,86  .585  * 59  .540  .140  3.8  1.27  -  -  .71  .680  .68  0  .265  .097  2.5  3.52  -  -  -  .362  .36  2. 62  0  .912  .287  3.1  3.22  -  -  .56  1.199  1. 20  .88  2.73  0  .560  .200  2.8  3.61  -  -  .45  .760  .76  0  1  1/2P-N  .5642  2189  547  4  10.3  1.03  .82  1, 37  0  .412  .120  3.4  2.19  -  -  1.05  .532  .53  1  1/2N-P  . 5407  1684  336  5  16.0  1. 60  .40  1.46  0  .608  .205  3.0  1,86  -  -  . .66  .813  .81  1  2P-N  .3614  1873  468  4  7.7  .77  1.12  1.52  0  .487  .130  3.7  2. 64  -  -  .58  .617  .62  1  2N-P  .4377  1938  484  4  9.1  .91  .43  1.45  0  .947  .237  3.9  1.88  -  -  .36  1.184  1. 20  1  -N-P  .5139  1995  399  5  12.8  1.28  .26  1.18  0  .600  .152  3.9  1.44  -  -  .68  .752  .75  ,4782  2457  491  5  9.7  .97  .30  .99  0  .488  .136  3.4  1.29  -  .76  .624  .62  .5765  2111  527  4  10.9  1.09  1.10  1.35  0  .830  .212  3.9  2.45  -  -  .55  1.042  1. 04  725  241  3  i  0  1.06  5.10  0  .520  .196  2.6  6.16  -  -  0  .716  .72  1  1/2N 1/2P  1  2N2P  4  P-N  * NOTE:  0  „2  U Gram pex Gram Dry Weight Extract  ro ON  27 Whenever the NET rate of carbon dioxide exchanged became high i n relation to other sets of the same nutrient treatment (Table III)» i t was very nearly always accompanied by a high concentration of the nitrate nitrogen species, while the nitrite nitrogen was either completely absent or else present i n very small quantities* The fact that i n the case of Jade, some sets did not contain either nitrate N (V plus) or n i t r i t e N (III plus) i n DETECTABLE amounts AT THE SAME TIME, furnished the opportunity to compare the function of either nitrogen species with respect to carbon dioxide assimilation* This was approached from tac aspects - one being the function of either nitrate or n i t r i t e i n regard to i t s role i n carbon dioxide assimilation IN CONJUNCTION with inorganic phosphorus present, the other involving separate analyses of the role of nitrate (or nitrite) ions and inorganic phosphorus. The resultant graphs showed the following interesting relationships. For Jade ( Figure 2) increased concentrations of n i t r i t e and phosphorus withi n the plant resulted i n an apparent increase i n the amount of carbon dioxide absorbed*  Higher concentrations of nitrate and phosphorus reduced  the net rate of carbon dioxide exchange*  The presence of BOTH nitrate and  n i t r i t e as well as phosphorus showed some stimulatory action upon carbon dioxide assimilation at increased levels within the plant* Using the second method of approach (Figure 3) when the phosphorus and nitrogen species were separated, i t was found that increased amounts of phosphorus tended to reduce the amount of carbon dioxide assimilated i n the presence of nitrate ions within the plant*  In the case of n i t r i t e being  exclusively present within the plant, increased concentrations of phosphorus resulted i n an apparent increase i n net carbon dioxide exchange rates*  FIGURE  2.  INTER RELATIONSHIP BETWEEN NITROGEN SPECIES A N D P H O S P H O R U S IN T H E P L A N T S A N D N E T R A T E S OF CARBON DIOXIDE E N C H A N G E D - JADE.  LEGEND -x>—  2 Assimilation NITRITE present only.  • t>«**  c o  r  —  T3  COo Assimilation NITRATE present only.  v  r  .  —  1.1-  ?  H  -•pM**K * C O Assimilation NITRATE and NITRITE both present.  -> <  l-O-  53  "  —  2X  •a  — » B U  •—  s  Visually fitted Lines.  l.l, 'i l-X  o u bo nl  s  l.o -  »•• ft-  'I .(, -  >  PI*  •1 -  I.O  1.1*  '•1*  i.0  —I '7  ,3  3  mePN  3+ and/or N  5 +  per GRAM of Leaf Dry Weight  ro  CO  LEGEND FIGURE  C02 Assimilation NITRITE present only.  A N A L Y S I S OF N I T R I T E A N D N I T R ' A T E C O N C E N T R A T I O N INFLUENCE UPON NET CARBON DIOXIDE E X C H A N G E RATES - JADE  3.  — A — a  Phosphorus associated With NITRITE NITRATE present only. Phosphorus associated with NITRATE  —X-  Visually fitted lines  •a M  T3  E & o u 60  s  <u 60  >a < n!  ©  of  OP  —x-DOf  ug N 3+ I—  >X<S  -So  ~\—  •7*  —r~ t.o  —i—  —r— J.6  —I  ug N  5+  per gram of leaf dry weight  ugP ro ?-  30 ""hen the data for Olympic (Table IV) were examined, a difference concerning the results of the chemical analysis became apparent* At NO TIME was any n i t r i t e nitrogen found to be present i n sufficient quantities to be measured*  In addition i t w i l l b e noted that at NO TIME had nitrate  nitrogen disappeared* Consequently i t was not possible to follow the same analytical procedures as had been applied to the Jade variety, due to the fact that a l l samples tested contained only nitrate ions, with phosphorus* Comparison of the chlorophyll a/b ratio (Table III) showed that deficiency of nitrogen i n plantsgenerally tended to reduce the value of this expression*  It was noted that chlorophyll b content increased i n  those plants grown i n nitrogen deficient media containing twice the standard amounts of phosphorus, while chlorophyll a was reduced to the extent as to be nearly equal to that of chlorophyll b*  It was also observed from these  measurements that the influence of a lack of nitrate i n the nutrient medium on chlorophyll a concentrations was much more severe than that on chlorophyll b levels*  The latter may have received a stimulus from the presence  of excess amounts of phosphorus provided that the nutrient solution was deficient i n nitrogen*  This observation was exemplified by the two  extremes where for the (2F - N) nutrient treatment, the amount of chlorophyll b reached i t s highest value while chlorophyll a was at i t s next to lowest concentration* In the case of the (2N - F) treatment, the chlorophyll a concentration reached itsmaximum value - a large increase over that found for the previously mentioned ( 2P - N) treatment*  Chlorophyll b changed but l i t t l e  i n concentration i n plantsgrown i n either (2N - P) or (2P - N) nutrient media. Analysis of chlorophyll a and b concentration fluctuations i n Olympic (Table IV) as a consequence of nutrient treatments did not appear  SI  LEGEND FIGURE  4.  C O M P A R I S O N OF C H A N G E IN C H L O R O P H Y L L a A N D b C O N T E N T IN R E L A T I O N T O N E T C A R B O N DIOXIDE E X C H A N G E RATES JADE.  .  o(ixPtY*0  Chlorophyll a  «(t«? 11 **)  Chlorophyll  z.o H 1.8-  \  OIF-")  T3  f.y •IN-P)  E (.1 -  4?-p)  ,  «0N  (N*p)  y  IN-P) •(P-h>  60  )(M-P)  I  •I  J  ' ( P-N/  O(H«-P)  J  I  >  O(N-P)  •(r*-p)  O(NtP)  0(Mt?)  O(itUP)  (lp-n)»lO(2p-n)  i.O  Average mg chlorophyll a, b  per gram of leaf dry weight  Ib  C O M P A R I S O N OF T H E E F F E C T OF N I T R A T E A N D NITRITE UPON CARBON DIOXIDE E X C H A N G E RATES AND CHLOROPHYLL a/b RATIO JADE.  LEGEND ( x)  Chlorophyll a/b ratio C0  2  assimilation in  presence of NITRATE only.  C0 assimilation in presence of NITRITE only. 2  (3.0>  P.H  {3.0 (3.2)  N-P  (Id) lit* 4N-P  Cit) H-P  A v e r a g e jig NOo NO^ per gram ofileaf dry weight o r  1.1  N-P  (vs)  ZP-rt  H.0  ^ M-P Cvi  l.fc  a.i  —7  ro  33 to show the same behaviour for this quality as that o f Jade* When nutrient treatment (P - N) (set 2) chlorophyll content was compared to that of (N - P) (set 2) l i t t l e variation i n chlorophyll b content was noted; chlorophyll a concentrations showed a considerable decrease in these sets*  I t was observed  that, contrary to the fluctuations i n chlorophyll a/b ratios obtained for Jade when grown under various degrees of nutrient stress, those of the Olympic variety remain nearly the same, even under severe nutrient stress, as was evidenced by the nutrient deficiency signs* Further exploration* with regard to variations i n both chlorophyll;, a and b, i n relation to net carbon dioxide exchange rates by plants of both varieties (Figures h and 5) when grown under various nutrient stress conditions, revealed that concentrations of chlorophyll a varied to a much greater extent (which was  generally i n accordance with nitrogen concentrations of  the nutrient medium) than chlorophyll b, under identical conditions of nutrient stress*  An example w i l l illustrate this observation*  Comparison of chlorophyll b concentrations of variety Olympic (Table  IV) sets two of nutrient treatments (N - p) and (2N - P) showed an 2  increase i n the latter treatment of only *032 mg pa r one gram of leaf tissue dry weight, while chlorophyll a content increases from .6 mg for the former set of treatment, to *9U7 mg for the latter series; a difference of nearly •3  mg* Analysis of Jade (Table III) for chlorophyll a and b content for  the same nutrient treatments, showed chlorophyll a content to increase by nearly .6 mg, whereas chlorophyll b increased only by *0J> mg per one gram of leaf tissue dry weight* The relationship of chlorophyll a content with carbon dioxide absorption by plants of the Jade variety when subjected to nutrient stress were subsequently examined*  From the resultant graph (Figure h) i t became  3li  apparent that the relationship of chlorophyll a content to the carbon dioxide exchange rate could not be determined with any degree of precision WITHOUT due consideration of the presence of either nitrate or nitrite within the plant's photosynthetic tissues* This conclusion was borne out by the observation that a nutrient solution, containing one half the standard amount of phosphorus, while being mono-deficient i n nitrate, was MORE beneficial with respect to CO2 assimilation i n the presence of nitrate than (2P - N) nutrient grown plants, whose tissues contained only nitrite ions*  ?his finding was especially interesting when i t was noted that very  l i t t l e difference existed between the chlorophyll a contents of plants grown i n (|p - N) and (2P - N) nutrient media* When the chlorophyll a/b ratios for set 3 and k of complete (N + P) treatment f o r variety Jade (Table H I ) were compared, i t was found that these ratios were identical*  However, the net carbon dioxide exchange rates of  these two sets were NOT the same*  Further perusal revealed that the net  carbon dioxide exchange rate i n the exclusive INTERNAL presence of nitrate ions was very nearly double the amount of C O 2 absorbed when only nitrite was present within the plant (Figure f>). when the table containing a summary of experimental data (Table 17) for Olympic was examined i t was found that some of the "erratic  11  sets of the  Hoagland (P - N) nutrient treatment contained comparatively high quantities of either phosphorus and/or nitrate nitrogen* This was especially noticeable for that group of plants whose net rate of carbon dioxide exchanged was found to be equal to the Compensation Point where nearly five mg of nitrate nitrogen was found to be  present  within the photosynthetic tissues - a fact which implies that nitrate ions i n this case do not appear to exert an enhancing effect upon net carbon  35 dioxide exchange rates* This i s contrary to that found for plants belonging to the Jade variety, for which the exclusive internal presence of nitrate was found to promote carbon dioxide assimilation*  36  GENERAL DISCUSSION Results obtained during the course of this investigation tended to be inconclusive with respect to establishing the reason for the existence of either intra-, or intervarietal differences of specimens belonging to the same species of Pi sum sativumX* Apart from the fact that the variability Ctf results might possibly be due to errors i n technique, such as mechanical stimulation of respiration as the result of handling, some of the results obtained i n measuring net carbon dioxide exchange rates of individual plants belonging to the pea variety Jade, showed the possible existence of some relationship with the internal presence of nitrite and/or nitrate within the photosynthetic tissues of the individual specimens. In addition, i t was found that l i t t l e i f any relationship existed between chlorophyll a, or alternatively the chlorophyll a/b ratio and the net ralie of carbon dioxide exchanged. Of the physical characteristics, the stomatal index of ventral surfaces of leaves tended to vary more extensively as the result of nutrient stress than the dorsal sides of the same leaves.  Another possibility for  the variability i n carbon dioxide exchanged by individual plants, not considered for the purposes of this experiment, was the existence of endogenous rhythmic variations with respect to carbon dioxide absorption. The facfc that some plants grown i n nitrate deficient media, sometimes contained appreciable amounts of either nitrate or n i t r i t e appears to indicate that the growth medium (Horticultural Grade Vermiculite) was somewhat less inert tHnamwas supposed. An alternative to the above would be that some nitrate, i n i t i a l l y present within the cotyledons^ of the pea plants had found i t s way into the plants, prior to excision.  37 The latter difficulty may be overcome by micro-chemical analysis for nitrate content of the intact seeds prior to germination, followed by analysis of nitrate of the excised colyledons.  The resultant difference  may then be used as a correctinn factor to be incorporated i n the f i n a l nitrate analysis of the photosynthetic tissues at the conclusion of the experiment. Finally two alternatives to this experiment are suggested as follows: A greater number of plants belonging to the same species should be tested with respect to variations in net carbon dioxide exchanve rates as the result of nutrient stress, and each analysis to be followed immediately by establishing the value of the stomatal index of both ventral and dorsal side of the leaves of each plant.  Such procedure would offer a  possibility of establishing a positive correlation between the net rate of carbon dioxide exchanged, and i t s stomatal index, thus establishing at least partly, the reason for variations i n CO2 assimilation. In addition, each plant should be analysed for both nitrate and/or n i t r i t e content of i t s photosynthetic tissues. Such procedure would possibly result in proving a positive correlation between the nitrate/nitrite content of leaves and net carbon dioxide exchange rates by each plant. A second method involving variability of carbon dioxide exchange rates, as caused by nutrient stress, would be to analyse a smaller number of plants of different varieties belonging to the same species for net rate of carbon dioxide exchanged, but on an hourly basis for a continuous period in order to establish i f endogenous rhythmic variations, when extant, are possibly subject to change as a result of nutrient stress. Although a continuous analysis of nitrate.nitrite would be highly desirable, each time a CO2 analysis i s completed, technical difficulties presently extant would  38  prevent such ananalysis to be carried out, without detaching the leaves from the plant under the above mentioned conditions of this experiment.  BIBLIOGRAPHY  1.  Allen, M.B.; Arnon, D.I.; Capindale, J.B."; Whatley, F.R.and Durham, L.J. 1955 - Photosynthesis inisolated chloroplasts III, Evidence for complete photosynthesis, J . Amer. Chem. Sec. J_7_ : klk9  2.  Anderson, F.G. and Bathurst, A.C. 1938 - Stikstof en fosfor i n lemoene, Boerderey, S.A. 13_ : 3^9  3.  Arnon, D.I.; Whatley, F.R. and Allen, M.B. 193k - Photosynthesis i n isolated chloroplasts II, Photophosphorylation the conversion of light into phosphate bond energy, J . Amer. Chem.  Soc. J_6 : 6324  k,  Aronoff, S,; Benson, A.A.; Hassid. W.Z. and Calvin, M. 19k7 - Distribution of carbon (ik) i n photosynthesizing barley seedlings, Science 105 : 66k  5.  Brachet, J.; Chautrerme, H. and Vanderhaeghe, F. 1955 - Recherches sur les interactions biochimiques entre le noyau et le cytoplasme chez les organismes unicellulaires II, Acetobularia mediterranea, Biochem et Biophys. Acta 18 : 'jkk  6.  Burstrom, H. 19^3 - Photosynthesis and assimilation of nitrate by wheat leaves, Ann. Agr. Coll. Sweden 11 : 1  7.  Ibidem 19^5 - The nitrate nutrition of plants, Ann. Agr. C o l l . Sweden 1^ : 1  8.  Carolus, R.L. 1935 - Experiences with rapid chemical tests for determination of nutrient deficiencies i n vegetable crops, Proc. Am. Soc. Hort. S c i . 3J. : 579  9.  Canada Department of Agriculture 1962 - Chemical Methods of Plant Analysis, Canada Dept. of Agriculture Research Branch Publication No. 106h, Phosphorus - Method 2.  10.  Curtis, 0.; and Clark, D.G. 1950 - An introduction to Plant Physiology, McGraw-Hill Co., New York, p. 60  11.  Eckerson, S. 192^ - Protein synthesis i n plants I, nitrate reduction, Bot. Gaz. 21  : 377 12.  Ibidem I929 - Influence of phosphorus deficiency on the metabolism of tomato, Abstr. Am. J . Botany 16 : 852  13.  Ibidem 1931 - Influence of phosphorus deficiency on the metabolism of tomato plants (Lycopersicon esculentum), Contr. Boyce-Thompson Inst.  _1  : 197  lk,  Evans, H.J. and Nason, A. 1953 - Pyridineunucleotide - nitrate reductase from extracts of higher plants, Plant Physiol. 28 : 233  15.  Fruton, J.S. and Simmonds, S. 1959 - General Biochemistry, second Ed. second print, J . Wiley & Sons Inc., New York, p. 182  16.  Ibidem - p. 871  17.  Giese, A.C. 1960 - Cell Physiology, W.B. Saunders Co., Philadelphia, Chapter 19, App. 1, p. 356  18.  Hageman, R.H. and Flasher, P. 1960 - Nitrate reductase activity i n corn seedlings as affected by light and nitrate content of nutrient media, Plant Physiol. 3J? s 700  19.  Hammer, K.C. 1936 - Effects of nitrogen supply on rates of photosynthesis and respiration in plants, Bot. Gaz. 97_ : Jkk  20.  H i l l , R. and Whittingham, C P . 1956 - Methuen monographs on Biochemical subjects, J . Wiley & Sons, Inc. New York, Photosynthesis, p. 57•  21.  Ibidem - p. 59  22.  Holden, M. 1952 - The fractionation and enzymic breakdown of some phosphorus compounds i n leaf tissues, Biochem. J . £1 : 433  23.  Kamen, M.D. 1963 - Primary Processes in Photosynthesis, Acad. Press, N. York, p. 31  2k.  Kraybell, H.R. 1930 - Plant metabolism studies as an aid i n determining f e r t i l i z e r requirements I, Ind. and Eng. Chem. 22 : 275  25.  Lundegardh, H. 1932 - Die Nahrstoff Aufhahme der Pflanze, Jena.  26.  McAllister, H.D. and Meyers, J . 19^0 - The timecourse of photosynthesis and fluorescence observed simultaneously, Smithonian Misc. C o l l . 29 s 6  27.  MacArthur, C.A. 1961 - Lecture Series - Phospholipids, the University of Saskatchewan.  28.  McCool, M.M. and Weldon, M.D. 1930 - The effect of sodium nitrate on the composition of the expressed sap of small grains, J . Am. Soc. Agron. 22 : h3k  29.  MacGillivray, X.H. 1926 m Importance of phosphorus i n the production of seed and'non-seed portions of the tomato f r u i t , Proc. Am. Soc. Hort. S c i . 22 : 37k  30.  Mayer, B.S. and Anderson, D.B. 1956 - Plant Physiology second Ed. kth print, D. Van Nostrand Co. New York, p. 60  31.  Ibidem - p. 305  32.  Mothes, K.; Bottger, I. and Wollgiehn, R. 1958 - Uhtersuchungen uber den Zu Sammenhang zwischen Nuklein saure und Eiweiszstoffwechsel in grunen blattern, Naturwiss, V? : 316  33.  Nichiporovich, A.A. 1955 - Tracer atoms used to study the products of photosynthesis as' depending on the conditions in which the process takes place, Proc. First Geneva Conf. on Peaceful Uses of Atomic Energy.  3I+.  Nightingale, G.T. 19^2 - Nitrate and carbonhydrate reserves i n relation to nitrogen nutrition i n Pineapple, Bot. Gaz. 103 : k09  35.  I960 - O f f i c i a l Methods of Analysis of the Association of O f f i c i a l Agricultural Chemists, Ninth Ed. ACAC Washington, D.C. p. 92. Method 6.100  36.  Pleasants, A.L. 1930 - The effdct of inorganic nitrate f e r t i l i z e r s on stomatal behaviour, Elisha Mitchell, Sci. Soc._h6> : 95  37.  Rainwater, F.H. and Thatcher, L.L. i960 - Methods for collection and analysis of water samples, Geological survey of water supply paper ihjk, U.S. Government Printing Office, Washington, D.C, Methods 25b and 25c, p. 216.  38.  Reed, H.S. 1907 - The value of certain nutritive elements to the plant c e l l , Ann. Bot. 21 : 501  39«  Salisbury, E.J. 1927 - On the causes and ecological significance of stomatal frequency with special reference to the woodland flora, Phil. Trans. Roy. Soc. B216 : 1  kO.  Schertz, F.M. 1929 - The effect of potassium, nitrogen and phosphorus upon the chloroplast pigments upon the mineral contents of the leaves and upon production i n crop plants, Plant Physiol. 4 : 269  kl.  Smillie, R.M. 1962 - Photosynthetic and respiratory activities of Growing Pea Leaves, Plant Physiol. 31 : 7l6  k2,  Smillie, R.M. and Fuller, R.C. 1960 - Photosynthetic and respiratory enzymes i n leaves, Federation Proc. 19 : 328  43.  Smillie, R.M. and Krotkov, G. 1961 - Changes i n the dry weight, protein, nucleic acid and chlorophyll contents of growing pea leaves, Can. J. Bot. 22 : 891  kk  Ibidem 1959 - Enzymic activities of sub-cellular particles from Leaves, IV, Photosynthetic phosphorylation and photosynthesis by isolated chloroplasts from pea leaves, Can. J. Bot. 3X : 1217  45.  Sprague, H.B. and Shive, J.W. 1929 - A study of the relations between chloroplast pigments and dry weights of tops in Dent Corn, Plant Physiol. 4 : 165  46.  Walter, H. 1929 - Plasmaquellung und assimilation, Protoplasma 6 : 113  kT,  Whatley, F.R.; Allen, M.B. and Arnon, D.I. 1955 - Photosynthetic phosphorylation as an anaerobic process, Biochem. et Biophys. Acta 16 : 605  48.  Ziegenspeck, H. 1944 - Vergleichende untersuchungen der Entwicklung der Spaltoffnungen von monokotyledonen und Dilkotyledonen im lichte der Polariskopia und Dichroskopie, Protoplasma 38 : 197  TABLE 1.  APPENDIX  INDIVIDUAL PLANTS NET CARBONDIOXIDE EXCHANGE RATES J A D E  JADE COMPLETE (N+P) MODIFIED (FeiiDTA) HOAGLAND SOLUTION  SET 1  2  3  REP  ppm  co  2  1  67  2  MB TEMP. C 0 / h r 2  21  dm* Leaf Area  Mg C  ° 2 1dm  1.0573  .6  1.7625  29  .4577  .5  .9152  3  18  .2838  .4  .7095  4  27  . 4261  .8  .5326  5  29 29  .4577 .4577  .6  .7629  6  12 12  .1814 .1814  .3  .6046  7  12 12  22.5  .1814 .1814  .4  .4535  1  16 15  21.5  .2515 .2367  .4  .6312  2  6 6  22.0  .09467 . 09467  .2  .4730  3  9 8  .1421 .1260  .2  .7105  4  7 8  .1104 .1260  .3  .3681  5  12 10  .1814 .1578  .4  .4735  6  9 9  .1421 .1421  .4  .3552  .2367 .2367  .31  .7635  .1578 .1421  .30  .5260  22  1  15 15  2  10 9  3  21 18  21.9  .3314 .2838  .42  .7785  4  17 17  22.0  .2683 .2683  .39  .6879  5  12 10  .1814 .1578  .28  .6478  6  17 15  .2683 .2367  .31  .8654  21.5  2  Mg Average D. Wt.  Soln/lOOOcc xn  Plant ppm  xp  xn  xp  FlOWE/^^  42  35  133  42  35  133  .8201  .5019  5526  4.5  42  .7115  8549  35  133  0  1.4  SET  REP.  4  1  2  3  4  5  6  ppm C0 2  Leaf Area TEMP, C0 /nr, d m 23.0 .4103  26  .4103  8  .1260  9  .1421  9  .1421  12  .1814  3  .04733  5  28. 3 .07888  9  .1421  8  .1260  7  .1104  D . Wt.  Average  2  2  26  Soln/lOOOcc  Mg  .77  .5302  .225  .5600  .20  .7105  .137  .3454  .23  .5743  .19  .5810  42  5502  7  xp  xn  9  DM  xp  Leaf Surface Area  -^Min.  133  4.6  2673  9  xn  35  TOTAL AVERAGE FOUR SETS . 6459 Mg C 0  Plant ppm F l o w j / ^  4.7  TABLE 1.  APPENDIX  JADE MODIFIED (FeEDTA) HOAGLAND SOLUTION (-P)  SET  1  1  2  3  REP.  ppm C0  Leaf Area g C0 /hr. dm M  TEMP  2  / U  z  2  Mg C0 /hr 1 dm 2  1  3 3  21.5 .04733 .04733  .5  . 0947  2  4 6  . 06310 .09467  .6  .1051  3  7 7  .5  .2200  4  4 5  .06310 .07888  .4  .1573  5  3 3  22.5 .04733 .04733  .3  .1570  6  5 4  .07888 .06310  .3  ,2620  7  5 4  07888 .06310  .3  .2620  1  4 6  .06310 .09467  .21  . 3004  2  4 4  .06310 .06310  .17  .3710  3  4 6  .06310 . 09467  .21  .3004  4  5 4  .07888 .06310  .18  .4271  5  3 2  .04733 .031S0  .16  .2961  6  2 2  .03150 .03150  .13  .2420  1  2 2  .03156 .03156  .14  .2254  2  1 1  .01578 .01578  .12  .1315  3  2 3  .03156 .04733  .069  .4573  4  .5 .5  .00789 .00789  .058  .1361  5  1 2  .01578 .03156  .063  .2504  6  22 . .1104 .1104  22.  .  23. (  2  Average  D. Wt  Soln/lOOOcc  Plant ppm  xn  xn  42  xp  xp  133  0  .1892  42  .3228  3013  0  42  . 2401  .1270  133  0  1.1  133  0  10.2  1.5  SET 4  REP. 1  2  3  4  5  6  ppm  co  2  Mg TEMP, C 0 / h r . 2  5  23.5 .07888  4  .06310  4  .06310  3  .04733  5  .07888  6  . 09467  2  .03156  2  .03156  2  .03156  1  .01578  1  .01578  1  .01578  Leaf Area dm  2  Mg CO2/&L 1 dm  z  .11  .7171  .12  .5258  .18  .4382  .13  .2427  .068  .4641  .063  .2504  Soln/lOOOcc Average  D. Wt.  42  .4563  xp  xn  .3021 Mg  2110  co  2  xn  xp  2 DM Leaf Surface Area  Flowr^——-  133  0  T O T A L AVERAGE FOUR SETS  Plant ppm  4.9  1.6  APPENDIX  TABLE 1. JADE MODIFIED (FeEDTA) HOAGLAND SOLUTION (=N)  SET  REP.  ppm C0 2  TEMP  Mg C0 /hr 2  Leaf Area dm 2  Mg C0 /nr 1 dm 2  2  17 18  19 21  .2683 .2838  .3  .8943  22 18  .3472 21.5 .2838  .2  1.736  14 12  .2209 .1894  .2  1.104  10 12  22.0 .1578 .1894  .2  .7890  9 9  .1421 .1421  .2  .7105  .2  .4733  -.01578 -.01578  .12  -.1308  22.5 .09467 .1260  Plant Total Mg D. Wt.  PJantt ppm  Soln/lOOOcc  xn  xp  Flow?  xp  35  133  35  133  ,8487  1  -1 -1  2  +2 +2  +.03156 +.03156  .095  +. 3314  3  -1 -1  - . 01578 -.01578  .085  -.1856  4  +5 +5  +.07888 +.07888  .097  +.8123  1*  6 8  23.5 .09467 .1260  .27  .3505  6 6  .09467 .09467  .16  .4041  5 4  .07888 .06310  .11  .7171  2 1  .03156 .01578  .20  .1578  2 2  23.5 .03156 .03156  .064  .4931  3 2  .04733 .03156  .056  .8451  3 3  23.5 .04733 .04733  .12  .3944  1 2  .01578 .03156  .054  .2921  .5 .5  .00789 .00789  .08  .5916  4 5  .06310 .07888  .16  .3943  22.  Plant Average  .2068  2.0  959  133  35  .4073  2.3  1826  4.5  133  35  .5007  * GIANT FORM  1829  3.2 T O T A L AVERAGE FOUR SETS .4916 M g C O / D M Leaf Area s  z  t SET  ppm  Leaf Mg Area TEMP. C02/hr. d m  REP  co  1  5 4  23.5 .07888 .06310  2  2 2  3  2  2  Mg C0 /hF, 1 dm 2  2  Mg Average D. Wt.  Soln/lOOOcc xn  xp  0  17.5  Plant ppm xn  xp  Flowr^' ^Min.  t  N„+1/2P  1  N1/2P  .124  .6361  .03156 .03156  .087  .3627  3 2  .04733 .03156  .092  .5144  4  3 3  .04733 .04733  .129  .3669  5  4 3  .06310 .04733  .093  .6744  6  4 4  .06310 .06310  .10  .6310  1  2 2  23.5 .03156 .03156  .07  .4508  2  3 5  .04733 .07888  .16  .2958  3  1 1  .01578 .01578  .135  .1168  4  1 2  .01578 .03156  .14  .1127  5  3 2  . 04733 .03156  .164  .2276  1  5 4  23.5 .07888 .06310  .1  .7888  2  6 6  .09467 .09467  .148  .6396  3  7 6  .1104 . 09467  .19  .5816  4  6 6  . 09467 .09467  .169  .5601  5  5 3  .07888 .09733  .15  .5258  6  6  . 09467  .136  .6961  !  t •  N.+2P  1  N2P  + 1/2N.-P  1  !  ' 1/2N-P  •  1  .5318  4. 5  2126 0  .2407  3268  1.5  70  133  0  2715 21  .6319  133  2.1  0  133  6. 0  0. 9  +2N, -F  SET  REP.  1  1  6 6  2  7 7  3  2N-P  -N-P  1  -N-P  +1/2N, 1 +1/2P  1/2N 1/2P  -i-2N 2P 2N 2P  ppm  1  co  2  Leaf Area Mg TEMP C0 /hr. dm  Mg  2  Average  2  .158  .5991  .1104 .1104  .169  .5810  9 9  .1421 .1421  .22  .6459  4»  6 5  . 09467 .07888  .16  .5916  1  5 5  23.5 .07888 .07888  .21  .3756  2  2 2  .03156 .03156  .21  .1502  3  4 3  .06310 .04733  .135  .4674  4  4 4  .06310 .06310  .21  .3004  5  6 6  .09467 .09467  .212 ' .4456  6  6 5  'i 09467 .214 .07888  1  7 8  23.5 .1104 .1260  2  7 7  3  23.5 .09467 .09467  .4423  .2  .5520  .1104 .1104  .23  .4800  7 7  .1104 .1104  .22  .5018  4  6 5  .09467 .07888  .20  .4733  5  3 4  .04733 .06310  .13  .3640  6  9 9  ,1421 . 1421  .32  .4125  1  9 9  23.5 .1421 .1421  2  8 7  .1260 .1104  .23  .5478'  3  10 10  .1578 .1578  .26  .6069  4  12 12  .1814 .1814  .39  .4651  5  9 10  .1421 .1578  .35  .4060  * Nos, 5 & 6 died before testing  Mg D. Wt.  Soln/lOOOcc xn 84  .6044  4410  2.2 133  17.5  .9 84  .4992  133  2.1  4319  Flowr^—• '"Min.  0  0  4390  „3 ' : .4763  xp  133  6.4  21  .4639  xn  0  2379 0  .3637  xp  Plant ppm  .9 133  70  1.4  1.3  APPENDIX  TABLE 2,  INDIVIDUAL PLANTS NET CARBONDIOXIDE EXCHANGE RATES  OLYMPIC  SET  REP.  1  1  2  2  6  Mg C0 /hr. 2  1 dm  2  22.8 .4734 .4261 22.9 .3156 .3156 .2367 .2367 23 .2525 .2367 .1421 .1421  .8  . 5917  .6  .5261  .4 .4 .4  .5917 .5917 .6315  .5  .2842  8 8 9 7 12 10 5 4 5 6 10 9  22.0 .1260 .1260 .1421 .1104 .1894 .1578 • .07888 .04733 .07888 . 09467 .1578 .1421  .29  .4348  .15  .9472  .32  .5918  .14  .5633  .30  .5260  9 11 2 6 5 3 6 5 4 -• 6 6 5 3 4 6 6 6  22.0 .1421 .1736 .09467 .07888 . 09467 .07888 .09467 .09467 .04733 .06310 . 09467 .09467  .36  .3944  .15  .6311  .19  .4982  .17  .5568 "  .13  . 3644  .26  .3641  3 4 5 1 2 3 4 5 6 3  co  TEMP. C 0 / n r .  Leaf Area dm  30 27 20 20 15 15 16 15 9 9  2  2  ppm  1  Total Mg Average D. Wt.  Soln/lOOOcc Mg xn xp  Pla nt pprr xn  xp  Flovjj,— "^Min.  42  35  133  42  35  133  .5250  .159 . 4961 .5932 3935  3.7 42  .4681 3761  3.0 133  35  5.7  4.6  SET  4  REP.  1  2  3  4  5  ppm  CO2  Leaf Arei Mg TEMP, C02/nr. dm z  3  23.5 .04738  5  .07888  7  .1104  7  .1104  6  .09467  5  .07888  5  .07888  5  .07888  2  .03156  2  .03156  Mg C0 /hr. 1 dm 2  2  .12  .3948  .15  .7360  .15  .6311  .074  1. 0648  .067  . 4710  Mg Average D. wt.  Soln/lOOOcc Mg 2n xp  42  .6595  Plant ppm xn  6. 9  TOTAL AVERAGE 9 , „ r Leaf Surface Area r  1 DM  Flowp^'  133  35  1540  FOUR SETS . 5614 MG CO2  xp  5.5  TABLE 2  APPENDIX  OLYMPIC - MODIFIED (FeEDTA) HOAGLAND SOLUTION (-P)  ppm C0  Leaf Mg area TEMP. C0 /hr dm  Mg  co /V 2  SET  REP.  1  1  6 6  23.0 .09467 .09467  .7  .1333  2  6 6  .09467 .09467  .5  .1893  3  3 25  . 04733 .03945  .4  .1143  4  5 3  .07888 .04733  .3  .2629  5  3 4  .04733 .06310  .4  .1143  6  4 3  .06310 .04733  .5  .1262  1  5 4  22.0 .07888 .06310  .157  .5024  2  4 3  .06310 .04733  .194  .3258  3  3 2  .04733 .03156  .186  .2547  4  2 2  .03156 .03156  .161  .1960  5  3 2  .04733 .03156  .141  .3366  6  3 2  .04733 .03156  .071  .6674  1  4 4  22.0 .06310 .06310  .12  .5258  2  5 5  .07888 .07888  .16  .4930  3  3 3  . 04733 .04733  .20  .2369  4  2 4  .03156 .06310  .11  .2878  5  4 2  .06310 .03156  .06  1.0516  6  2 2  .03156 .03156  .07  .4508  2  3  2  2  2  1 dm  2  Average  Mg D. Wt.  Soln /1000cc Mg xn xp 42  Plant ppm xn  xp  133  0  .1567 42  .3804  42  .5059  0  2535  2430  Flowr^-^" ^Min.  5.2  3.6  5.2  .9  0  I  SET 4  REP. 1  2  3  4  6  ppm co 2  Leaf Area Mg TEMP. C 0 A r . dm  Mg 1 dm*  z  2  5  23.5 .07888  .12  . 6573  6  .09467  3  .04733  .09  .5258  3  ,04733  3  .04733  .11  .4302  2  .03156  2  23.5 .03156  .117  .2765  3  .04733  .085  .5568  3  .04733  2  .03156  .069  .4573  2  .03156  Average  Mg D. Wt.  Mg  xp  xn 42  .4839  Soln/lOOOcc  xn  xp  TOTAL AVERAGE 2  DM2 Leaf Surface Area  Flowr^— ^Min. 133  0  2212  FOUR SETS . 3817 Mg C 0  Plant ppm  6.7  1.0  . TABLE  APPENDIX  2  OLYMPIC - MODIFIED (FeEDTA) HOAGLAND SULUTION (-N)  SET 1  2  3  4  ppm co  REP  2  Mg TEMP. C 0 / . 2  h r  Leaf Area, dm  Mg COo/ Rr 1 am 2  1  24 24  21  .3788 . 3788  .4  .9470  2  16 15  21.5  .2525 .2367  •  .8416  3  14 16  .2209 .2525  .3  .7363  4  11 10  .1736 .1578  .4  .4340  5  15 16  .2367 .2525  .3  .7890  6  11 13  .1736 .2051  .2  .8680  1  -3 ~2  -.04733 -.03156  .11  -.4307  2  +2 +1  +.03156 +.01578  .10  +. 3784  3  -3 0  -.04733 0  .125  -.3784  4  -6 -6  -.09467 -.09467  .098  -.9660  1*  7 6  .1104 .09467  .19  .5810  2  4 • 3  .06310 .04733  .09  .7011  3  4 5  .06310 .07888  .08  .7887  4  2 2  .03156 .03156  .05  . .6312  1  -.5 -.5  -.00789 -.00789  .10  -.07888  2  3 3  .04733 .04733  .147  .3212  3  3 3  .04733 .04733  .13  .3644  4  0 0  0  5  0 0  0 0  .044  0  0 0  .064  0  0  6  22  22.0  22  22.  3  .061  Average  Mg D. Wt.  Soln/lOOOcc Mg xp xn  Plant ppm xp  xn  Flowr^_—-  0  35  133  0  35  133  .7695  -.3671  10.5  1220 0  .6755  4.7 133  35  9.4  995  2.4 133  35  0  1260  8.2  2.6  725  15.3  3.2  0  .3428  TOTAL AVERAGE FOUR SETS . 3551 Mg C0 /DM Leaf Area 2  2  APPENDIX  TABLE 2  OLYMPIC - MODIFIED (FeEDTA) HOAGLAND SOLUTION  SET •N+1/2P  1  •N+1/2P  1  •N+2P  1  f•N+2P  +1/2N/-P  1  1/2N-P  +2N-P  2N-P  1  REP  ppm C0 2  Leaf Area Me TEMP. C 0 / n r . d m 2  Mg Average  2  1  3 3  21.5 .04733 .04733  .088  .5378  2  5 3  .07888 22.0 .04733  .144  .5477  3  4 3  .06310 .09733  .08  .7887  4  6 6  .09467 . 09467  .247  .3832  1  4 5  23.0 .06310 .07888  .164  .3847  2  2 3  .03156 .04733  .147  .2147  3  5 5  .07888 .07888  .172  .4586  4  3 3  .04733 .04733  .122  .3877  1  3 2  23.0 .04733 .03156  .10  .4733  2  4 5  .06310 .07888  .109  .5789  3  3 4  .04733 .06310  .09  .5258  4  3 4  .04733 .06310  .06  .7888  5  3 2  .04733 .03156  .14  . 3370  1  3 3  23.5 .04733 .04733  .131  .3613  2  6 5  .09467 .07888  .22  .4303  3  3 2  .04733 .03156  .14  .3380  4  3 2  .04733 .03156  .076  .6227  Soln/lOOOcc Mg Mg xp D. Wt. xn 0  .5642  .4377  1938  133  6.1  4.5 133  0  7.3  1684  Flowr^ ^Min.  3.3  70  1873  84  xp  133  5.5  21  .5407  xn  17.5  2189 •• 0  .3614  Plant ppm  1.9 133  0  5.8  1.7  Leaf Area Mg TEMP , C02/hr. dm 2  Mg  CO2 / hr.  1 dm2  SET  REP  1  1  3 3  21.5 .04733 .04733  .07  .6761  2  4 3  .06310 .04733  .16  .3943  3  2 2  .03156 .03156  4  6 5  .09467 .07888  .13  .7282  5  4 6  .06310 .09467  .15  .4206  1  3 3  22.0 .04733 .04733  .13  .3641  2  3 3  .04733 .04733  .08  .5916  3  6 6  .09467 . 09467  .19  .4982  4  6 6  .09467 .09467  .20  .4733  5  5 5  .07888 .07888  .17  .4640  1  6 5  22.0 .09467 .07888  .16  .5916  2  6 5  . 09467 .07888  .16  .5916  3  5 6  .07888 .09467  .16  .4930  4  8 7  .1260 .1104  .20  .6300  -N-P  -N-P  +1/2N, +1/21,1 1  1/2N 1/2P  +2N, +2P  ppm  1  I  J2N 2P  co  2  Average  Soln,/lOOOcc Mg Mg xp D. Wt. xn 0  .5139  Flowr/'^ /^Min.  1.3 133  17.5  4.9  2457  2111  xp  133  5.9  84  .5765  xn  0  1995 21  .4782  Plant ppm  1.5 133  70  5.4  4.4  TADLE 3.  APPENDIX  ANALYSIS OF STOMATAL INDEX (I = 100) x  Treat- Leaf Variety ment Side  No, Ho.. E Stomata Epid S Cells  S+E  I  No. -E No. S Epid Treat- Leaf Variet) ment Side (Stomata] Cells  S  -i-  E  I  3  6  9  33. 3  27..3  1  7  8  12..5  11  27..3  3  7  10  30.0  7  8  12.5  1  7  8  12.5  4  7  11  36.4  1  6  7  14..2  6  2  8  10  20,0  2  7  9  22.2  7  1  8  9  11.1  2  8  10  20..0  8  3  8  11  27..3  3  8  11  27..3  9  3  9  12  25..0  2  7  9  22.2  10  3  6  9  33.3  2  6  8  25..0  11  2  7  9  22.2  2  5  7  28.4  12  1  7  8  12.5  2  7  9  22.2  13  2  10  12  16.-6.  1  6  7  14.-2  14  1  8  9  11.1  2  6  8  25.-0  15  1  9  10  10.0  2  7  9  22.2  16  1  9  10  10.0  1  6  7  14.2  17  1  10  11  9.1  2  7  9  22.-2  18  2  13  15  13.-2  3  7  10  30.0  19  1  9  10  10.0  4  10  14  28.4  20  1  11  12  1  6  7  14.-2  21  1  9  10  10.0  3  7  10  30.0  22  1  7  8  12.5  1  5  6  16. -6  23  1  7  8  12.5  2  7  9  22.2  24  1  6  7  14.2  2  7  9  22.-2  25  1  6  7  14.2  3  7  10  30.-0  26  2  6  8  25.0  2  6  8  25.0  27  1  6  7  14. .2  1  7  8  12.5  28  1  6  7  14.2  4  8  12  33.-3  29  1  4  5  20.0  2  8  10  20.0  30  1  5  6  16.6  1  9  10  10.0  31  1  6  7  14.2  1  7  8  12.5  2  8  10  20.0  2  3  8  11  3  3  8  4  1  5  1 Olympic  N+P  Upper  OLYMPIC (AVERAGE) Standard DORSAL Stomatal Index  Jade  N+P  Uppei  8.33  JADE (AVERAGE) 17.1  Standard DORSAL Stomatal Index  21.7  No. E (Epid Treat- Leaf No. S Variety ment Side (Stomata) Cells)  -  1 Olympic  P-N  Uppei  1 '" 1 ''• ;  2  S + E- I  5  6  16.6  5  6  No. E Treat? Leaf No. S (Epid Variety merit Side Stomata) Cells) S + E P-N - Uppe :  9  33.3  8  11  27.3  3  6 '  16. 6  3  Jade  I  3  3  6  9  33.3  2  6  8  25.0  4  2  8  10  20.0  3  7  10  30.0  5  1  6  7  14.2  2  7  9  27.2  6  1  6  7  14.2  3  6  9  33.3  7  2  5  7  28.4  1  7  8  12.5  8  3  8  11  27.3  3  7  10  30.0  9  2  6  18  25.0  2  8  10  20.0  10  3  8  11  27.3  3  8  11  27.3  11  1  7  8  12.5  1  6  7  14.2  12  2  7  9  22.2  2  7  9  22.2  13  2  8  10  20.0  1  6  7  14.2  14  2  6  8  25.0  2  7  9  22.2  15  2  7  9  22.2  4  9  13  30.4  16  2  5  7  28.4  3  9  12  25.0  17  1  6  7  14.2  2  6i.  8  25.0  18  1  6  7  14.2  2  6  8  25.0  19  2  6  8  25.0  2  7  9  22.2  20  2  7  9  22.2  4  7  11  39.6  21  3  7  10  30.0  3  6  9  33. 3  22  2  6  8  25.0  1  7  8  12.5  23  2  9  11  18. 2  1  7  8  12.5  24  1  6  7  14.2  2  5  7  28.4  25  2  6  8  25.0  2  6  8  25.0  26  2  6  8  25.0  1  5  6  16..6  27  2  8  10  30.0  2  5  7  28.4  28  2  7  9  22. 2  3  9  12  25.0  29  2  6  8  25.0  3  7  10  30.0  30  2  8  10  20/0  3  6  9  33.3  OLYMPIC (AVERAGE Stomatal Index (P-N)  22.1  JADE (AVERAGE) Stomatal Index (P-N)  25.4  No.. E No, S (Epid . Treat- Leaf side (Stomata) Cells) Variety ment  S+E  i  No. E Treat- Leaf No. S. (Epid Variety ment Side (Stomata) Cells) S + E  I  2  8  10  20 .  20.0  2  9  11  18.2  16  18,7  2  10  12  16.6  13  15  13,2  2  9  11  18.2  .6  16  22  27,3  1  9  10  16.0  6  5  15  20  25,0  2  7  9  22.2  7  5  13  18  27,5  1  9  10  10.0  8  4  12  16  25.0  3  6  9  33. 3  9  4  14  18  22.2  1  6  7  14.2  10  4  14  18  22, 2  4  6  10  40.0  11  4  12  16  25.0  2  7  9  22.2  12  4  14  18  22.2  1  6  7  14.2  13  3  14  17  17.4  3  8  11  27.3  14  4  14  18  22,2  3  9  12  25.0  15  3  15  18  16,5  1  8  9  11.1  16  4  13  17  23,2  3  9  12  25.0  17  2  13  15  13,2  1  8  9  11.1  18  2  13  15  13.2  2  18  19  5  15  20  25.0  4  8  12  33.3  20  3  12  15  20.0  3  7  10  30.0  21  4  15  19  20.8  4  7  11  36.4  22  4  16  18  11.1  2  7  9  22.2  2  16  18  11.1  4  7  11  36.4  24  4  15  19  20.8  2  7  9  22.2  25  2  8  10  20.0  3  7  10  30.0  26  1  5  6  16.6  2  6  8  25.0  27  2  6  8  25.0  4  9  13  30.4  28  2  7  9  22.2  1  7  8  12.5  29  2  6  8  25.0  1  6  7  14.2  30  2  9  11  18.2  3  7  10  30.0  4  17  21  19.9  2  3  12  15  3  3  13  4  2  5  1 Olympic  23  N-P  Uppei  Jade  N-P  Upper  ...  OLYMPIC (AVERAGE) Stomatal Index (N-P) 20, 6  JADE (AVERAGE) Stomatal Index (N-P)  22.7  loi-.; 20.0  Treat-; Variety ment  No. E Leaf No, S (Epid Side (Stomata) Cells) S + E  I  Variety  No. E (Epid Treat- Leaf No. S ment Side (Stomata Cells) S + E  I  1  6  7  14.2  20. 0  3  5  8  37.5  5  20.0  3  8  11  27'i 3  5  7  28.4  1  6  7  14.2  1  5  6  16.6  3  7  10  30.0  6  1  6  7  14.2  2  5  7  28.4  7  1  5  6  16.6  2  6  8  25.0 '  8  1  4  5  20,0  2  6  8  25. 0  9  2  4  6  33.3  2  5  .7  28,4  10  2  4  6  33.3  3  7  10  30.0  11  1  3  4  25.0  1  5  6  16.6  12  1  4  5  20.0  3  6  9  33. 3  13  2  4  6  33. 3  1  5  6  16.6  14  2  8  10  20'. 0  3  7  10  30.0  15  1  4  5  20.0  2  5  7  28.4  16  1  4  5  20. 0  2  6  8  25.0  17  1  4  5  20.0  1  8  9  11.1  18  2  4  6  33.3  3  8  11  27. 3  19  1  4  5  20.0  2  7  9  22. 2  20  1  4  5  20.0  3  7  10  30.0  21  1  4  5  20. 0  1  6  7  14. 2  22  2  3  5  40.0  3  6  9  33.3  23  1  3  4  25.0  2  5  7  28.4  24  1  4  5  20. 0  2  7  9  22.2  25  1  3  4  25.0  2  6  8  25.0  26  1  5  6  16.6  1  6  7  14.2  27  1  3  4  25.0  3  7  10  30.0  28  1  3  4  25.0  2  6  8  25.0  29  1  3  4  25.0  1  7  8  12.5  1  3  4  25.0  1  5  6  16.6  1  3  4  25.0  2  1  4  5  3  1  4  4  2  5  1 Olympic  30  N+P  Lowei  1  N+P  Lower  JADE (AVERAGE)  OLYMPIC (AVERAGE). Standard VENTRAL Stomatal Index  Jade  23.5  Standard VENTRAL Stomatal Index  24.0  Treatment"  Variety  Leaf Side  No. S No. E (Stomata) (Epid • Cells)  S+E  I  TreatVariety m ent  P-N  Lower  No. E (Epid No. S Cells) S + E (Stomata)  I  2  6  8  25.0  2  5  7  28.4  2  1  5  6  16i6  2  4  6  33.3  3  3  4  7  42.6  3  6  9  33.3  4  2  3  5  40.0  3  3  6  50/0  5  2  4  6  33.3  3  5  8  37.5  6  1  5  6  16. 6  3  4  7  42.6  7  1  5  6  16.6  2  5  7  28.4  8  1  3  4  25.0  3  7  10  30.0  9  2  3  5  40.0  2  4  6  16. 6  10  1  3  4  25.0  1  2  3  33.3  11  1  5  6  16.6  1  2  3  33.3  12  3  4  7  42.6  1  3  4  25.0  13  2  5  7  28.4  2  4  6  33.3  14  1  4  5  20.0  2  2  4  50.0  15  1  4  5  20.0  3  4  7  42.6  16  1  5  6  16.6  2  4  6  33.3  17  1  4  5  20.0  2  7  9  22.2  18  2  5  7  28.4  2  6  8  25.0  19  1  5  6  16.6  4  :'.8  10 •.  40.0  20  2  3  5  40.0  3  4  7  42.6  21  1  5  6  16.6  2  4  6  33. 3  22  2  4  6  33.3  1  4  5  20.0  23  1  4  5  20.0  3  6  9  33.3  24  1  4  5  20.0  4  6  10  40.0  25  1  4  5  20.0  2  4  6  33.3  26  2  4  6  33.3  3  3  6  50.0  27  2  6  8  25.0  2  1  3  66.6  28  3  4  7  42.6  1  3  4  25.0  29  3  7  10  30.0  2  4  6  33.3  1 Olympic  P-N  Lower  OLUMPIC (AVERAGE)) Stomatal Index (P-N)  Jade  Leaf Side  JADE (AVERAGE) 26.6  Stomatal Index (P-N)  34.9  Treat Variety ment  No. E Leaf No. S (Epid Side [Stomata) Cells)  S+ E  I  No. E Treat- Leaf No. S (Epid Variety ment Side [Stomata) Cells  S+ E  I  3  5  8  37.5  33.3  i:.-  4  5  20.0  10  30.0  2  6  8  25.0  4  6  33.3  1  3  4  25.0  1  4  5  20.0  3  4  7  42.6  6  1  4  5  20.0  2  5  7  28.4  7  4.-.  7  36.3 -  1  4  5  20.0  8  1  4  5  20.0  1  5  6  16.6  9  2  5  7  28.4  2  6  8  25.0  10  1  4  5  20.0  2  5  7  28.4  11  1  3  4  25.0  1  4  5  20.0  12  1  3  4  25.0  2  3  5  40.0  13  1  2  3  33.3  1  3  4  25.0  14  1  3  4  25.0  1  4  5 , 20.0  15  2  4  6  33.3  1  3  4  25.0'  16  1  3  4  25.0  1  2  3  33.3  17  2  4  6  33.3  2  3  5  40.0  18  3  5  8  37.5  1  4  5  20.0  19  1  3  4  25.0  2  5  7  28.4  20  1  3  4  25.0  1  3  4  25.0  21  1  4  5  20.0  1  4  5  20.0  22  1  4  5  20.0  1  3  4  25.0  23  2  4  6  33.3  2  6  8  25.0  24  3  3  6  50.0  1  4  5  20.0  25  4  4  8  50.0  2  4  6  33.3  26  1  5  6  16.6  2  4  6  33.'3  27  1  2  3  33,3  1  3  4  25.0  28  2  3  5  40.0  2  3  5  40.0  29  2  3  5  40.0  2  4  6  33.3  30  1  3  4  25.0  2  3  5  40.0  1  5  6  16.6  2  3  6  9  3  3  7  4  2  5  1 Olympic  N-P  Lower  ii  Jade  N-P  Lower  - -J  OLYMPIC (AVERAGE) Stomatal Index (N-P) 29,1  JADE (AVERAGE) Stomatal Index (N-P)  28.0  

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