Narayan MogerGayatree Mohapatra2016-11-122016-11-122011http://krishikosh.egranth.ac.in/handle/1/85247Microbial metabolic repertoire represents the primary resources from which new biomolecules are derived. Recently, the rise of resistance in pathogens renewed the interest on actinobacteria. In the present study, a total of 248 actinomycetes colonies were recovered from rhizosphere, endorhizosphere of 27 medicinal plants, an aquatic weed and road side run off soil. Randomly 114 actinobacteria isolates were picked for functional characterization against Rhizoctonia solani, Sclerotium rolfsii, Colletotrichum capsici, Ralstonia solanacearum and 40 actinobacteria against an insect Plutella xylostella. Out of which, 25, 85.5, 16 and 10 per cent of total isolates displayed an antagonism of (90-100) per cent against Rhizoctonia solani, Sclerotium rolfsii, Colletotrichum capsici, Ralstonia solanacearum respectively, and 20 isolates displayed more than 50 per cent mortality against Plutella xylostella. 26 isolates were selected for identification due to its functional significance through ARDRA. They were found to be members of Streptomyces, Microbispora, Nonomuraea and Amycolatopsis genera. Similarly, 16S rDNA sequence analysis of 11 extra potent isolates out of 26 isolates clustered them into Streptomyces genera. The REP PCR fingerprinting of whole genome of all these 26 isolates displayed 75 per cent identity among themselves. Supplementing to functional capability of these isolates 76 and 52 per cent total isolates were positive for NRPS and PKS I genes respectively. Cloning of partial sequence of PKS I gene of AUDT 248 exhibited an identity to the antibiotics, stambomycin gene cluster which was further supplemented with LC-MS analysis. Similarly, partial PKS I gene of AUDT 217 showed homology to the modular PKS of unknown biosynthetic identity.Plant BiotechnologyThesis