Abstract
Plant growth and development requires nitrogen as essential elements, which supplied by symbiotic bacteria rhizobia in association with leguminous plants. Plant growth promoting Rhizobacteria are capable of promoting plant growth by colonizing the plants root and enhances symbiotic and associative nitrogen fixation. This work aimed isolation, characterization and PGPR activity of the bacteria from cultivated and non-cultivated leguminous plants. Seven strains of Rhizobium species were isolated from six non-cultivated wild leguminous plants and three Rhizobium strains were isolated from cultivated leguminous plants. Plant root´s nodule collected from different regions of Ranchi, Jharkhand. Bacteria were isolated for its characterization and PGPR activities, such as IAA production, Phosphate solublization, HCN production, Ammonia production. During this work six non-cultivated leguminous plants were identified namely Tephrosia (Tephrosia purpurea), Tick clover (Desmodium tortuosum), Karanj (Pongamia pinnata), Shisham (Dalbergia sissoo), Lupin (Lupinus albus), Gulmohar (Delonix regia). From these plants seven Rhizobium species were isolated (RC1, RC2, RC3, RC4, RC5, RC6, RC7) and characterized. Three isolates (RC8, RC9, RC10) were also characterized from cultivated leguminous plants namely Dolichos bean (Lablab purpureus), Arhar (Cajanus arietinum), Gram (Cicer arietinum). These ten isolates showed PGPR activities, which confirmed through IAA, HCN and ammonia production tests. The aim of this study is to isolate Rhizobacteria from wild and cultivated leguminous plants, which have PGPR activity. Inoculum of all these Rhizobium species isolated from non-cultivated wild leguminous plants can exploited in plant growth promotion.