EFFICACY OF FUNGICIDES AND BIO AGENTS IN MANAGING THE BLACK LEAF SPOT DISEASE OF PAPAYA INCITED BY ASPERISPORIUM CARICAE (SPEG.) MAUBLS. Shreedevasena, S.K. Manoranjitham, L. Rajendran and R. ParimaladeviAbstract Black leaf spot of papaya caused by Asperisporium caricae is one of the new emerging destructive disease of papaya that cause considerable yield loss of 5 to 29 per cent. Hence, experiments were conducted to determine the efficacy of both bio agents and fungicides in in vitro and in-vivo against Asperisporium caricae causing black leaf spot of papaya. In vitro studies of fungicides were carried out by using poisoned food technique and dual culture technique for bio agents carried out at aseptic conditions. Results revealed that the fungicide trifloxystrobin 25% + tebuconazole 50% WG, propiconazole 25% EC and zineb 68% + hexaconazole 4% WP were most effective which inhibited growth of the pathogen at all concentrations. Among the biocontrol agents tested, T. asperellum and B. subtilis PG 12 was found to be most effective showing 84.07 and 78.88 per cent per cent reduction. The compatibility study revealed that the B. subtilis PG 12 were compatible with effective fungicides trifloxystrobin 25% + tebuconazole 50% WG and propiconazole 25% EC under in vitro conditions, whereas the fungal bio agents T. asperellum doesnât show any compatibility with the any of the fungicides tested. The treatments which were found effective under laboratory conditions were evaluated at glass and field conditions. The results revealed that the treatment with B. subtilis PG 12 (seed treatment @ 10 g/kg + soil application @ 20 g/plant Ist DAP) + foliar spray of trifloxystrobin 25 % + tebuconazole 50% WG @ 0.45 g/l recorded the least disease incidence under glass and field conditions. |