Insecticidal Activity of Extracts, Fractions, and Pure Molecules of Linnaeus against Aphid, Koch.

Koch is a polyphagous and major pest of leguminous crops causing significant damage by reducing the yield. Repeated application of synthetic insecticides for the control of aphids has led to development of resistance. Therefore, the present study aimed to screen the insecticidal activity of root/stem extracts/fractions, and pure molecules from Linnaeus against for identification of lead(s). Among root extract/fractions, the -hexane fraction was found most effective (LC = 1828.19 mg/L) against , followed by parent extract (LC = 2211.54 mg/L). Among stem extract/fractions, the -hexane fraction (LC = 1246.92 mg/L) was more effective than the water and -butanol fractions. Based on GC and GC-MS analysis, among different compounds identified in the -hexane fraction of root and stem, ethyl palmitate (known to possess insecticidal activity) was present in the highest concentration (24.94 to 52.95%) in both the fractions. Among pure molecules, pareirarineformate was found most effective (LC = 1491.93 mg/L) against , followed by cissamine (LC = 1556.31 mg/L). Parent extract and fractions of possess promising activity against aphid. Further, field bio-efficacy studies are necessary to validate the current findings for the development of botanical formulation.