The use of the nodule bacteria as a remedy for expanding adaptive possibilities of soybean under drought conditions

Abstract

Symbiotic systems created by soybean variety Almaz (Glycine max (L.) Merr.) and strains of nodule bacteria Bradyrhizobium japonicum 646, РС09, В157 with were investigated under different water supply are investigated (30 and 60 % field capacity, FC). It was shown that drought inhibited the process of nodulation, depending on the functional and adaptive capacity of each of the microsymbionts. The number and mass of root nodules on plants decreased compared to control plants under insufficient watering. Insufficient watering (30 % FC) negatively impacted the functioning of symbiotic systems Glycine max (L.) Merr.—Bradyrhizobium japonicum depending on the drought duration. Strains of Bradyrhizobium japonicum PC09 and B157 formed more drought-tolerant symbiotic systems. They had higher nitrogen fixing activity under reduced moisture supply (30 % FC) and during the recovery period compared to the Bradyrhizobium japonicum 646 strain. It was shown that with increasing drought duration (from the 3rd to the 10th day) the difference in physiological and symbiotic parameters between treated and control plants increased, but with the resumption of watering they partially leveled depending on the inoculant strain.