Influence of Environmental Factors on Interstrain Competition in Rhizobium japonicum†

摘要: The effect of several biotic and abiotic factors on the pattern competition between two strains Rhizobium japonicum was examined. In Minnesota soils, Waseca Waukegan, strain USDA 123 occupied 69% (Waseca) 24% (Waukegan) root nodules Glycine max L. Merrill cv. Chippewa. 110 2% in soil 12% Waukegan soil. Under a variety other growth conditions—vermiculite, vermiculite amended with soil, Hawaiian soils devoid naturalized strains—USDA more competitive than 123. addition nitrate to or presence antibiotic-producing actinomycetes rhizosphere soybeans did not affect strains. However, preexposure young seedings before transplantation into altered significantly. Chippewa for 72 h increased percentage by from 2 55%. Similarly, Waimea, nodule occupancy 7 33% after 72-h preexposure.