Assessment of fungicides, botanicals and bio-control agents for integrated management of Alternariaster leaf blight of sunflower.

Abstract

Ten botanicals were evaluated against Alternaria leaf blight by in vitro technique, spore germination was less in extracts of Garlic and Neem at all concentrations. In pot culture studies, low leaf blight was observed in plants sprayed with extracts of Garlic and Neem, while 83% disease observed in pathogen check.Among bioagents , Tv 3, Tv 4, Ts 3, Ts 10, T 6, Th 7, Tv 7, Th 10, Tv 2, B. megaterium, B. circulans and P. fluorescens recorded low leaf blight intensity. 25 biocontrol agents, ten botanicals and seven new fungicides were evaluated under glass house condition. Among twenty five biocontrol agents, Th 7 recorded low leaf blight severity and out of ten botanicals, Garlic extracts showed low disease severity. Among screened seven fungicides, SAAF recorded low leaf blight severity. From the above studies, efficient botanical, potent biocontrol agent and effective fungicides were used for the integrated management of Alternaria leaf blight under glass house and field conditions. Under glass house conditions, among the various combinations seed treatment with the iprodione+carbendazim (Quintal) combination followed by spraying of propiconazole - 0.1% showed 74% disease reduction as compared to pathogen check. Spraying of Garlic (0.5%) and Trichoderma (0.2%) reduced disease severity by 69.9%. Seed treatment with carbendazim + mancozeb (SAAF) along with the spraying of 0.1% concentration of the same fungicide exhibited reduction of 67%, While 82.6% disease was recorded in pathogen check.Under field conditions, among the various combinations seed treatment with iprodione + carbendazim (Quintal) combination followed by spraying of Propiconazole (0.1%), Garlic (0.5%) and Trichoderma (0.2%) recorded 31.4% disease followed by 33.4% disease in treatment where seed treatment with the iprodione + carbendazim (Quintal) + spraying of propiconazole-0.1% during 2010-2011. During 2011-2012, out of various combinations seed treatment with iprodione + carbendazim (Quintal) combination followed by spraying of propiconazole (0.1%), Garlic (0.5%) and Trichoderma (0.2%) resulted 24.4% disease with disease reduction of 64.8% over pathogen check followed by Trichoderma (0.2%) which recorded 32.5% disease .