Srinivasa Rao Vattikonda, Nageswara Rao Amanchi and Sabita Raja S.
The anxiety to control pests has resulted in indiscriminate use of pesticides in the field causing environmental pollution and posing threat to human safety and public health. Amongst the alternatives, uses of bio pesticides have been found effective, eco friendly and could possibly provide a viable option. In the present study Forskolin was used to assess feeding intensity of Papilio demoleus larvae against citrus leaves for its antifeedant activity. Papilio demoleus is commonly known as citrus swallowtail. The caterpillars feed on leaves, prefer blossoms and young ones. Attack by larvae on young trees result in a great loss of foliage causing general weakness and sometimes death also. Forskolin is a plant extract, which was isolated from the Coleus forskohlii. A large leaf disc 36.5 sq.cm of lemon was used after spraying with different concentrations such as 50, 100, 150, 200ppm uniformly on either side by using an atomizer and placed in a petridish. Single Papilio demoleus fourth instar larva was introduced into each petridish and observations were noted at 24hrs and 48hrs duration. Mean average of the 10 sets were taken for the activity and the consumed area was measured graphically. The % of leaf area protection was calculated and control sets were maintained simultaneously. A significant antifeedant activity was observed against fourth instar larvae of Papilio demoleus at 200ppm.