Insecticidal Potential of Pongamia pinnata Seed Fractions of Methanol Extract Against Earias vitella (Lepidoptera: Noctuidae)
[Insektizide Potenz von Methanol-Extrakten aus Samen von Pongamia pinnata gegen Earias vitella (Lepidoptera: Noctuidae)]
Singh, R.; R.,
The efficacy of karanj [Pongamia pinnata (Linnaeus 1758) Pierre 1781] seed (both mature as well as immature) fractions (hexane, chloroform and acetone at 0.5, 1.0, 1.5 and 2.0%) in disrupting various behavioural and physiological activities of Earias vittella (Fabricius 1794) w as assessed. Mature seed hexane and chloroform fractions (1.0%) exhibited more than 65% and 75% first instar larval mortality respectively. While, more than 70% third instar larval feeding deterrence was noticed in mature seed hexane at the lowest concentration tested (0.5%). Besides, a pronounced decrease in food consumption and utilization indices viz, CI, GR, ECI, AD and ECD was observed when fourth instar E vittella larvae were allowed to feed on fractions treated okra fruit blocks. Adults when fed on the extract treated sucrose diet (0.1, 0.2, 0.3 and 0.4%) exhibited a marked reduction in egg laying and subsequent egg hatching. Such fractions also deterred the adult ♀♀ from egg laying when applied on to the oviposition substrate (no-choice, choice and without actual contact condition). Hatching inhibition of one-day old eggs on application of fractions was noticed. Among the fractions (hexane, chloroform and acetone) hexane followed by chloroform fraction showed maximum activity. Mature seed fractions gave better results than the immature one.