Isolation of pathogenic Streptomyces spp. and determination of variability among the strains collected from potato

A study was undertaken during 2008-2009, 2009-2010 and 2010-11 cropping seasons to isolate the variability(s) of Streptomyces spp. from lesion common scab affected potato tubers in Northern parts Bangladesh (Rangpur division). There were twelve different pathogenic species isolated, which for colony colour, spore ornamentation, chain morphology, other physiological characteristics (temperature, pH, melanin production, colour secret oatmeal broth medium, carbon utilization growth response NaCl solution) reaction. Overall all collected isolates grow well within temperature range 25°C 30°C. In present investigation, it observed that S2 S11 could at pH 4.50. It found increased as value medium increased. Considering isolates, S5 agreed with description S. scabies having smooth, grey spores borne spiral chains, producing utilizing eight recommended ISP diagnostic sugars raffinose a sole source carbon. Rest eleven not identify.