Effects of Karanj (Pongamia pinnataVent) Methanolic Seed Extracts and Fractions on Growth and Development ofPlutella xylostellaL. (Lep., Yponomeutidae)

The effects of larval feeding for 48 h on cabbage leaves treated with different concentrations of karanj (Pongamia pinnata Vent) seed methanolic extracts and their fractions were investigated against the biology and food consumption-utilization indices of Plutella xylostella under laboratory conditions. The treatments included 2.5, 5.0, 7.5 and 10.0% of methanol extracts of mature and immature seeds and 0.5, 1.0, 1.5 and 2.0% concentrations of fractions (acetone, chloroform and hexane) to compare with karanj oil (1.0%), acetone and water as controls. The experiments revealed that all the treatments with extracts and fractions of mature and immature seeds and karanj oil (1.0%) adversely affected biological parameters of the pest. At similar concentrations, mature seed extracts and fractions proved better than immature seed and at higher concentrations effects were more pronounced against first than against third instar larvae. Consumption-utilization indices were also adversely affected by all the treatments particularly at higher concentrations.