Co-inoculation of Urea and DAP Tolerant <Emphasis Type="Italic">Sinorhizobium meliloti</Emphasis> and <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> as Integrated Approach for Growth Enhancement of <Emphasis Type="Italic">Brassica juncea</Emphasis> |
| |
Authors: | Dinesh K Maheshwari Sandeep Kumar Bhavesh Kumar Piyush Pandey |
| |
Institution: | (1) Department of Botany and Microbiology, Gurukul Kangri University, Haridwar, 249404, Uttarkhand, India;(2) Department of Microbiology, S.B.S.P.G. Institute of Biomedical Sciences and Research, Balawala, Dehradun, 248161, Uttarkhand, India |
| |
Abstract: | Two plant growth promoting rhizobacteria––Sinorhizobium meliloti RMP1 and Pseudomonas aeruginosa GRC2 were studied for integrated nutrient management to obtain improved yield of Brassica juncea. Low concentrations of urea and diammonium phosphate (DAP) stimulated the growth of both S. meliloti RMP1 and P. aeruginosa GRC2. 1 M of urea and 0.35 M of DAP was found lethal for RMP1, while 1.3 M and 0.37 M concentrations of urea and DAP proved to
be toxic for GRC2. Lc50 was observed as 0.49 M of urea and 0.15 M of DAP for RMP1, and 0.66 M urea and 0.18 M of DAP for GRC2. Urea and DAP adaptive variants of RMP1 and GRC2 was isolated. Adaptive bacterial variants had better growth rates at sub-lethal (Lc50) concentrations of urea and DAP as compared to non-adaptive variants. They also retained plant growth promoting attributes
similar to non adaptive variants. GRC2 and RMP1 did not affect the growth of each other and were chemotactically active for DAP, urea as well as root exudates of
B. juncea. Both the isolates colonized well in the rhizosphere of B. juncea, as their populations were recorded ≈5 log10 cfu g−1 after 120 days. Interestingly, the colonization ability was found even better when both strains were co-inoculated, as their
population was recorded in the range of ≈6 log10 cfu g−1 after 120 days. In field trials, application of RMP1 and GRC2 resulted in significant increase in biomass and yield of B. juncea as compared to control. However, yield was better with application of half dose and full dose of recommended fertilizers.
Interestingly, the biomass as well as yield improved further when both isolates were applied together along with half dose
of recommended fertilizers. |
| |
Keywords: | Sinorhizobium meliloti Pseudomonas aeruginosa Urea Diammonium phosphate |
本文献已被 PubMed SpringerLink 等数据库收录! |
|