Fifty seven Streptomyces isolates were isolated from scabbed tubers and soil of infected potato fields. The isolates were classified based on color of colonies, spores and diffusible melanin production and sporphore morphology. They synthesized pigment when grown on MSSA, YME and OMA-T media and they seemed to have utilized different ISP carbon sources. Twenty two isolates of Streptomyces were selected to use in the further trials. These twenty two isolates differed in their utilization abilities to different ISP carbon sources and the most appropriate chemicals for growth of isolates were glucose followed by raffinose, mannitol and arabinose, respectively. Also, they were Gram positive and had positive infection of roots and shoots of radish seedlings. Variation in aggressiveness was observed among isolates when using mini-tubers assay in pathogenicity. Genetic diversity among thirteen Streptomyces scabies isolates were studied using three primers i.e., 1, 6 (10 mer) and P (15 mer). Primer 1 was the best in revealing the clear similarity and diversity among the tested Streptomyces isolates. |
