Screening of different Pseudomonas and Bacillus Spp. for production of L-glutamic acid and impact of their cell-free filtrate on growth and yield of brinjal (Solanum melongena)

Abstract

Amino acids can play a different role in plants such as nitrogen source, hormonal precursor and stress reducing agents. L glutamic acid is involved in several plant metabolic processes. The objectives of present work were to evaluate the L glutamic acid production by different agriculturally important Pseudomonas and Bacillus species and to determine the effects of L glutamic acid containing cell-free filtrate on growth and yield of brinjal. An experiment was conducted in a completely randomized block design (CRBD). Out of eight different strains of Pseudomonas, the highest L glutamic acid was detected in Pseudomonas fluorescens 128 (1.397 g/l) followed by Pseudomonas fluorescens NSPL07 (1.073 g/l) and Pseudomonas striata RCOF153 (0.563 g/l). Similarly, out of six different species of Bacillus, moderate L glutamic was detected in Bacillus amyloliquefaciens MTCC10439 (0.232 g/l). The growth stimulatory effects of L glutamic acid containing filtrate (200 ppm) was also studied and it was found that all growth parameters of brinjal (plant height, fruits per plant, fruit yield etc) improved significantly. Results indicated that bacterial secretion containing L glutamic acid along with other amino acids have bio-stimulatory effects and it should be used to enhance the plant growth and yield.