UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Ecological specificity of growth promoting bacteria for interior spruce (picea glauca x picea engelmanii)? O’Neill, Gregory Arthur


Soil, rhizobacteria and interior spruce seed originating from two disparate ecosystems were used to examine the effect of rhizobacterial inoculation and the role of coexistence between rhizobacteria, seed provenances and soil sources on germination and spruce seedling growth in two experiments. Statistically significant enhancement of germination due to inoculation with bacteria was rare. Germination of seed inoculated with coexistent bacteria was significantly lower than germination of seed inoculated with non-coexistent bacteria. Inoculation of seed with bacteria resulted in significant enhancement of seedling growth in both experiments. Maximum shoot and root dry weight increases of 53% and 67%, respectively, were observed. The effect of inoculation on seedling growth varied greatly with seed provenance and soil source. Coexistent bacteria (i.e. originating from the same location as the target seed or soil) were not more effective growth promoters than non-coexistent bacteria. However, uninoculated seedlings grown incoexistent soil had 27% and 35% heavier shoot and root dry weights, respectively, than uninoculated seedlings grown in non-coexistent soil. The shoot and root biomass stimulation decreased to 17%and 23%, respectively, when coexistent pasteurized soil was used, suggesting that both biotic andabiotic soil factors may have contributed to seed-soil coexistence specificity. Novel findings in these experiments include the detection of: significant bacterial plant growth promotion of interior spruce; plant growth promotion by a Staphlococcus species; and adaptive relationships between seed and soil factors.

Item Citations and Data


For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.