Soybean lectin as a component of a composite biopreparation involving Bradyrhizobium japonicum 634b

The effects of the composite biopreparation Bralec (involving the soybean-specific root nodule bacterium Bradyrhizobium japonicum strain 634b and soybean lectin at concentrations of 500, 50, and 5 μg/ml as major components) on the development and functional activity of soybean-rhizobium symbiosis (development phases of one leaf, four true leaves, and budding) was studied. It was demonstrated that pretreatment of seed with this preparation stimulated the development of both the macro-and microsymbionts. The experimental plants displayed an active accumulation of biomass (4–42% higher compared with the variant with inoculation), development of root nodules (the number increased by 11–110% and the weight by 27–157%), and elevated nitrogen-fixing activity (by 45–204%). The soybean yield increased by 8–10% upon treatment with Bralec 500 and Bralec 5 as compared with the traditional seed bacterization with root nodule bacteria.