Abstract

Efficacy of acetone extraction (1%) of various parts of bajra plant was tested on parasitization by Trichogramma chilonis Ishii and predation by Chrysoperla zastrowi sillemi (Esben-Peterson). Laboratory bioassay with acetone extracts of young leaves, old leaves, flowers and stems of bajra plant with T. chilonis and C. zastrowi sillemi revealed their kairomonal activities under in vitro condition. Treating irradiated eggs of Spodoptera litura (Fab.) with acetone extract of flowers of bajra recorded the parasitization of 16.54 per cent by T. chilonis on third day after inoculation which increased from 52.31 to 70.12 per cent on fifth and seventh day after inoculation and they were 7.31, 18.46 and 26.12 per cent when the eggs were treated with acetone alone on third, fifth and seventh days after inoculation, respectively. Maximum emergence (69.21%) was observed with acetone extract of flowers followed by acetone extract of young leaves (53.23%). The highest predation by C. zastrowi sillemi on acetone extract of flowers treated eggs of S. litura was recorded (70.18%) whereas it was 29.87 per cent in acetone treated eggs.

Keywords: Chrysoperla zastrowi sillemi, Corcyra cephalonica, Kairomone, Pennisetum glaucum, Spodoptera litura, Trichogramma chilonis