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The present investigation reports on larvicidal efficacy of plant extracts of Nux-vomica, Strychnus nuxvomica against Diamond back moth (DBM). In this investigation shade dried and powdered nux-vomica plant samples (leaves, root bark, stem bark, seed and fruit rind) were extracted with organic solvents ethanol, methanol, acetone, hexane and chloroform and also formulated as Emulsifiable Concentrates (EC) using surfactant and solvents. This formulated plant extracts were tested against third instar larvae of DBM for larvicidal efficacy using leaf disc bioassay method under laboratory condition. Among the five solvent extracts tested, hexane extracts of root bark 11.11 EC @ 2 % showed highest larval mortality of 76.66 % followed by seed 14.25 EC, leaf 16.66 EC, stem bark 12.50 EC and fruit rind 12.50 EC extracts exhibited maximum mortality @ 2 % concentration recording 66.66, 63.33, 56.66 and 40.00 per cent mortality respectively. Positive and negative control such as respective solvent and water showed 10.00 and 3.33 % larval mortality respectively. The results of these experiment clearly indicate that nuxvomica plant possess promising larvicidal action against diamond back moth. [ABSTRACT FROM AUTHOR]

Survey, monitoring and documentation of entomofauna of cocoa was carried out in three cocoa growing states viz., Tamil Nadu, Kerala and Andhra Pradesh during 2014-2015. Results revealed that a total number of 23 species of insect pests and 13 species of natural enemies were documented and identified. Among the insect pests, 14, 2 and 7 species were sucking pests, borers and defoliators, respectively. Among the natural enemies, 7 species of predators and 6 species of parasitoids were documented and identified on different insect pests of cocoa. Among the insect pests, sucking pests were found to be predominant and maximum number of entomofauna were recorded in major coco growing areas of Tamil Nadu. From the results it was concluded that the list of entomofauna documented can enhance the knowledge on diversity of the entomofauna associated with cocoa in three different cocoa growing states. Sucking pests were found to be predominant and caused huge yield loss in Tamil Nadu and Kerala. While in Andhra Pradesh pod borer and bark eating caterpillar were found to be predominant causing severe yield loss. This information provides a base for development of location specific Integrated Pest Management module. [ABSTRACT FROM AUTHOR]