Effect of Pgant Extracts on Fecundity of

摘要

The tobacco caterpillar, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is a cosmopolitan and polyphagous pest affecting several crops like cotton, pulses, oilseeds, vegetables, etc. all over the world and causing loss of agricultural production. The larvae are mostly active at night, cause extensive damage, particularly in tobacco nurseries (Atwal and Dhaliwal, 2005). The management of this pest using synthetic chemicals has failed due to insecticidal resistance (Mehrotra, 1993). A number ofplant species like Azadirachta indica A. Juss, Melia azedarach Linn., Lantana camara L. Moldenke., Cannabis saliva Linn., Nerium indicum Mill., Eucalyptus sp., Ricinus communis Linn., Solarium nigrum Linn, etc are known to possess insecticidal properties, although only a few of these have been exploited commercially. Earlier workers studied the Antifeedent and toxic effects of different plant extracts on the larval mortality of Spodoptera frugiperda and S. litura (Hernandez and Vendramin, 1997 and Singh et al.,2006). An effort was made in the present investigation to assess the effect of seven plant species on the egg laying of tobacco caterpillar, a cosmopolitan and polyphagous pest affecting several crops.