EFFECT OF Bradyrhizobium japonicum AND SALICYLIC ACID ON PHOTOSYNTHETIC PIGMENTS CONTENTS AND SOYBEAN GROWTH UNDER PHOSPHORUS AND WATER DEFICIT CONDITIONS

The application of rhizobacteria and salicylic acid is a promising approach in crops production and they can induce resistance against abiotic stress, however, their combined effect is not fully elucidated A pot experiment was conducted to study the effect of rhizobacteria Bradyrhizobium japonicum applied alone or in combination with salicylic acid (SA) on photosynthetic pigments (chlorophyll a. b, total chlorophyll, and carotenoids) and plant growth of soybean under low phosphorus and drought conditions. The plants exposed concomitantly to low P and temporary water deficit registered the lowest growth and photosynthetic pigments status. Integrated use of rhizobacteria and SA (0.5 mM) increased photosynthetic pigments contents in leaves under normal as well as under water deficit conditions. Their effect was more pronounced in plants subjected to P deficiency and water stress. Results showed that seed treatment with rhizobacteria in conjunction with foliage application of salicylic acid increased plant growth irrespective of soil moisture level. It is inferred that rhizobacteria and SA work synergistically to promote growth of plants under moisture and nutrient deficit conditions.