Vol. 5, Issue 2, Part A (2023)

A field experiment was conducted to test the toxicological bioefficacy of three plant extract namely: Ageratum conyzoides Linn., Argemone mexicana Linn., Arachis hypogea Linn.and one synthetic chemical were worked out against third instar larvae of Eucosma critica Meyrick under field conditions. The observations were taken constantly to record the food plants and other alternate host plants of Eucosma critica Meyrick. It was observed that arhar, Cajanus cajan (L.) Millsp., is the only host plant of Eucosma critica Meyrick. The Ageratum conyzoides Linn. gave the 80.18 per cent larval mortality, which is followed by, Endosulfan (64.62 per cent), Argemone mexicana (42.33 per cent) and Arachis hypogea Linn. (28.51 per cent) were found to be significant, when compared to control. It was obvious from the results that reduction of third instar larvae was very high, when treated with Ageratum conyzoides Linn. Followed by Endosulphan, Argemone mexicana Linn. and Arachis hypogea Linn. were found to be significant, when compared to control and other three selected plant oils and endosulfan.