Toxicity, Repellency and Antifeedant effects of Inula racemosa Hook.f. (Asteraceae) against Thholium castaneum Herbst (Coleoptera: Tenebrionidae)

摘要

The insecticidal, antifeedant and repellent effects of chloroform extract of root of Pushkarmoola, Inula racemosa Hook. f. (Asteraceae) and its non-polar and polar fractions are reported against the adults of Tribolium castaneum Herbst. The bioassays were conducted using broken wheat grains. Cent per cent mortality was observed on 11,15 and 19~(th) day of exposure at 15mg g~(-1) to non-polar, polar fractions and root extract, respectively. The order of toxicity was petroleum ether fraction (non-polar)> acetonitrile fraction (polar)> chloroform root extract. Insecticidal bioassay was concentration and time dependent whereas repellent assay was independent of duration but varied with concentration. The maximum repellency was observed after 5 h at 15mg g~(-1) concentration of root extract. In antifeedant study, weight loss in treated grains (0.27%) was non-significant but less as compared to control (0.36%) after 21 days of treatment showing no antifeedant effect. This study suggested that non-polar fraction of I. racemosa was most toxic among the tested fractions and also possessed repellent effect.