Assessment of Status of Sugarcane Coccids in Cauvery Delta Region

Studies were carried to assess the current status of sugarcane coccids occurring in Cauvery delta region. The coccid fauna surveyed in five sugarcane factory areas revealed the occurrence of scale insects, viz., Melanaspis glomerata (Green), Marsipococcus marsupiale, Aulacaspis madiunensis (Zehntner), and Aclerda japonica. Among the four coccids, M. glomerata was found to occur widely and intensively in all the sugar factory areas surveyed. The occurrence of M. marsupiale and A. japonica was very stray in the sugar factory areas except in Cauvery sugars where it was comparatively higher. A. madiunensis was found to occur commonly in alternate hosts like Erianthus sp. and Saccharum spontaneum types in Kothari sugars area but its incidence on sugarcane hybrids was very stray.. The occurrence of A. japonica was found to be in low levels in all the five sugarcane factory areas surveyed and nil incidence of A. madiunensis was recorded in Arignar Anna sugars. The occurrence of M. marsupiale was recorded only at nine months after planting and harvest while A. madiunensis and A. japonica were recorded only during harvest. M. glomerata was more or less equally abundant both in plant and ratoon crops in the sugarcane varieties commonly cultivated in the Cauvery delta region. Infestation of all the four coccids was at their highest during harvest in all the five sugar factory areas indicating their proliferation on the standing crops till harvest.