Antagonistic Streptomyces Selection to Broad Spectrum for Biological Control of Colletotrichum spp., Causal Agent of Anthracnose in Chilli

Antifungal activity on mycelium growth inhibition of Colletotrichum capsici (21 isolates), C. acutatum (37 isolates), C. gloeosporioides (1 isolate) and C. coccodes (1 isolate) tested by dual culture method showed that all antagonistic Streptomyces spp. inhibited the mycelium growth of the fungi, as Streptomyces-PR22 had strongest activity followed by Streptomyces-PR78, PR15, PR13, PR87, PR84 and PR33, respectively. The spore germination of 4 species of Colletotrichum was inhibited by culture filtrate of Streptomyces-PR22 while the other Streptomyces presented good results for some species only: PR33 for C. capsici, C. acutaturn, and C. gloeosporioides, PR87 for C. gloeosporioides and C. coccodes, PR15, PR78 and PR84 for C. coccodes. All isolates of antagonistic Streptomyces produced hydrolytic enzymes such as chitinase, (2)1,3 glucanase. For protease enzymes was produced by Streptomyces-PR78, PR15, PR84 and PR87. In a greenhouse experiment, Streptomyces-PR22 and Streptomyces-PR87 sprayed weekly from-seedling or from- flowering stage until fruit harvesting reduced number of diseased fruits in both chili cultivars var. Prik kheenu and Num Kiew as effective as fungicide benomyl application. The study shows that antagonistic Streptomyces-PR22 or PR87 is powerful alternatives to fungicide for control anthracenose disease of chilli caused by Colletotrichum and increase crop yields.