Abstract

INFLUENCE OF ISOLATED PLANT GROWTH PROMOTING RHIZOBACTERIA (PGPR) ON THE GROWTH OF BRASSICA JUNCEA L.

Tanya Sinha* and Chandrawati Jee

Abstract

Plant Growth Promoting Rhizobacteria (PGPR) are beneficial bacteria that colonize plant roots and enhance plant growth by wide variety of mechanisms which includes direct and indirect mechanisms like nitrogen fixation, phosphate solubilization, phytohormone production, antifungal activity, etc. Eleven bacterial isolates were identified from rhizosphere of Brassica juncea L. using morphological, biochemical and molecular analysis. The isolates were designated as AN1, AN2, AN3, AN 4, AN5, AN6, AN7, AN8, AN9, AN10 and AN11. Subsequently to investigate the effects of PGPR isolates alone and in two combinations named consortium (Cons. 3) and consortium (Cons. 4) were made for combination studies in Brassica juncea L. along with absolute control. Isolated PGPRs showed significant difference among seed germination percentage (GP) and germination index (GI) over to controls. The treatments with AN4, AN5, AN6, Cons. 3 and Cons. 4 play significant role in enhancement of shoot length in all developmental stages of the plant growth along with fresh weight of the plant. AN4, AN5, Cons. 3 and Cons. 4 showed significant increase in root length, weight and fresh pod weight of Brassica juncea. These results show the potential to use selected PGPRs in order to improve yields in Brassica crop.

Keywords: PGPR, Brassica juncea L., rhizosphere, isolates, Consortium.