Effect of organic sources of nutrients on defoliator, Catopsilia pyranthe (L.) (Lepidoptera: Pieriidae) of senna

A field experiment was conducted at Agricultural College and Research Institute, Madurai during March - September 2007 to evaluate the influence of various organic sources ofnutrients on defoliator, Catopsilia pyranthe (L) of senna. It was found that senna plots applied with vermicompost (2t/ha) + neem cake (250 kg/ha) + bio-fertilizers (2kg/ha) + NPK (40:40:40 kg/ha) had significantly less incidence of defoliator, recording the overall mean leaflet damage of 3.5% in main crop and 2.1% in ratoon crop. Leaf samples obtained from senna plots applied with vermicompost + neem cake + bio-fertilizers + NPK recorded higher phenol, ash and sennoside contents and the same treatment enriched the population of beneficial micro-flora like consortia of bacteria, fungi and actinomycetes in soil. Yield in the effective treatment was the highest of 1544.0 kg dry leaves/ha and 546.7 kg pods/ha with cost benefit ratio of 1: 1.28.