Development of promiscuous and effective rhizobia nodulating kharif legumes
| dc.contributor.advisor | Gera, Rajesh | |
| dc.contributor.author | Subha | |
| dc.date.accessioned | 2018-10-29T06:32:58Z | |
| dc.date.available | 2018-10-29T06:32:58Z | |
| dc.date.issued | 2018 | |
| dc.description.abstract | Clusterbean, cowpea, mothbean, mungbean, pigeonpea and urdbean are the commonly grown kharif legumes of arid and hyper-arid zones. Inoculation of effective and promiscuous rhizobia improves the nitrogen fixation as well as plant biomass yield of legumes. So, the present investigation has been undertaken for development of promiscuous and effective rhizobia nodulating kharif legumes. A total 209 rhizobial isolates were isolated from 31 soil samples collected from different districts of South-West Haryana and Rajasthan. All rhizobial isolates were checked for their nodulation ability and efficiency in six different kharif legumes. Three rhizobial isolates (PKR177, PKR188 and PKR194) have ability to nodulate all these six crops but with poor nodulation efficiency. So, these three rhizobial isolates were mutagenised by EMS (0.15%) for enhancing nodulation efficiency in all six legumes and it was found that, out of 300, only 4 rhizobial mutants (PKR177m30, PKR188m85, PKR194m24 and PKR194m93) exhibited increase in nodulation efficiency in all the legumes. Rhizobial mutant PKR188m85 was tagged with gfp gene to check its nodulation occupancy in all the legumes. Twenty five native rhizobial isolates, 4 mutants and one GFP marked strain having capability of nodulating more than three crops were evaluated for different traits. Most of the native and mutant rhizobia were able to grow up to 40oC, 4% salt and 30% PEG concentration. All rhizobia were able to produce IAA and ammonia, however, 47 and 63% rhizobia had the ability of bacteriocin production and phosphate solubilization, respectively, whereas, 83% of rhizobia were able to utilize ACC. Most of rhizobia were found to have intrinsic resistance to ampicillin, chloramphenicol, nalidixic acid and streptomycin upto concentration of 100 μg/ml. All the rhizobia showed the presence of nodC gene, however, nifH gene amplification was observed in 26 rhizobia. ARDRA results showed that all the isolates were distributed in to two major groups with sub and sub groups and divergence among these started at 63 percent similarity with restriction enzymes, MspΙ and HaeΙΙΙ. Rhizobial mutants PKR177m30 and PKR188m85 showed better nodulation efficiency and plant growth parameters than control in chillum jar and pots under both sterilized as well as unsterilized conditions. It was observed that promiscuous GFP marked strain showed more than 80% nodule occupancy under unsterilized conditions.The promising promiscuous rhizobial mutants were identified as Rhizobium sp. on the basis of ribo-typing of partial 16S rRNA gene. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810082441 | |
| dc.keywords | Legume, Rhizobia, GFP marked strain, Traits, Mutants, Promiscuous | en_US |
| dc.language.iso | en | en_US |
| dc.publisher | CCSHAU | en_US |
| dc.sub | Microbiology | en_US |
| dc.subject | null | en_US |
| dc.theme | Development of promiscuous and effective rhizobia nodulating kharif legumes | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | Development of promiscuous and effective rhizobia nodulating kharif legumes | en_US |
| dc.type | Thesis | en_US |