Department of Entomology, CCS Haryana Agricultural University, Hisar, India, 125 004
Online published on 15 October, 2011.
Studies on the insecticidal properties of ginger, Zingiber officinale roots against Earias vittela were conducted in CCS Haryana Agricultural University, Hisar, India under laboratory conditions. First instar larvae were allowed to feed on okra fruits treated with methanolic extract and its fractions for 48 h and then restored to normal food. Different parameters like larval period (10.7–17.3 days), larval weight (28.5–65.8 mg), pupation (14.4–83.3%), pupal period (8.3–17.0 days), adult emergence (7.8–77.8%) were adversely effected and increased larval mortality (12.2–78.9%). In consumption and utilization studies, consumption index ranged from 3.40 in 2.0% benzene to 8.64 in 2.5% methanol. Similarly growth rate (0.11–0.41 mg per day), efficiency of conversion on ingested food (1.5–7.7%), approximate digestibility/assimilation efficiency (61.0,92.4%) and efficiency of conversion of digested food (1.6–9.2%) also differed significantly. Food deterrence affects were also studied by using fourth instar larvae on weight basis. The antifeedancy ranged from 9.4% in 0.5% hexane to 46.3% in 2.0% chloroform fraction.
Extract, fractions, Earias vittella, okra fruits