Biocontrol activity of Streptomyces isolate SDSRO-13 against Colletotrichum spp. causing anthracnose disease of chilli (Capsicum annuum L.)

A total of 18 Streptomyces species were isolated from the rhizospheric soil of maize. Among 18 isolates, SDSRO-13 showed strong inhibition against Colletotrichum spp. of chilli. SDSRO-13 was identified as Streptomyces sp. based on morphological, biochemical and 16S rRNA partial gene sequence analysis. In this study, two strains of Colletotrichum sp. were used for pathogenicity test. For in vivo antifungal activity, spore suspension of the test pathogens were used on the fresh chilli fruit by making a small puncture on the fruit, in completely sterile conditions and incubated for up to 21 days. The chilli fruits treated with SDSRO-13 and test pathogens showed no disease symptoms. The infected fruits were subjected for Koch’s postulate test and they showed the similar morphological features compared to the pure cultures of the pathogens. We conclude that Actinomycetes, especially members of the genus Streptomyces are potential biocontrol agents which offer safer alternative management strategy to control the chilli fungal pathogens.