The magnitude of insect pest problem in castor is quite high in southern India where castor is grown mainly as rainfed crop, resulting in lower seed yield. The major pest problems in castor include the defoliators, semilooper, Achaea janata L.; tobacco caterpillar, Spodoptera litura Fab.; capsule borer, Conogethes punctiferalis Guenn. and the sucking pests, leafhopper, Empoasca flavescens Fab.; thrips, Retithrips syniacus Mayet and whitefly, Trialeurodes ricini Misra (Lakshminarayana and Raoof, 2005). Yield loss of 19 to 85 per cent has been reported in castor due to semiloopers and capsule borers (Singh et al., 1992).
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