Effect of bean inoculation by endophytic bacteria isolated from nodules

Abstract

Bean nodule isolates F4, F5, and F6 contained, in addition to rhizobia, bacteria of other species (bacilli), which showed neutralism to them and weak fungistatic activity against Fusarium oxysporum. Treatment of seeds with isolates at a dose of 107 cells / ml twice stimulated the growth of the axial organs of seedlings compared to the control without inoculation, but this effect was not detected when bacteria were added at a dose of 109 cells / ml. The field effectiveness of bacterial biologicals depended both on the variety and on the hydrothermal conditions of the environment. Inoculation of variety Zolotistaya with isolates F4 and F6 contributed to increase of the mass of seeds by 19 and 28 % in comparison with the control in a wide range of hydrothermal conditions. Treatment of the Ufimskaya variety had a positive effect on the seed yield only when interacting with isolate F5 at GTC ?1. Elsa bean inoculation was ineffective. With sufficient moisture supply (GTC 1) in individual cultivar-strain combinations, both an increase and a decrease in the number of nodules were observed in comparison with non-inoculated control, which correlated with the yield. At GTC <1, in most variants of bacterial treatments, nodules were not formed, and the yield was lower than the control in plants with nodules under these conditions. Treatment of plants of the Ufimskaya variety with isolate F6 and the variety Zolotistaya with isolate F4 had a positive effect on reducing the development of root diseases.