UJI AKTIVITAS INSEKTISIDA EKSTRAK DAUN SERAI TERHADAP ULAT DAUN KUBIS (Plutella xylostella L.) DI LABORATORIUM

Abstract

The study was conducted to evaluate effects of varied concentrations of methanol extract of lemongrass, Andropogon nardus L. (10.5%, 9.5%, 8.5%, 7,5%, 6.5%, and 0% as control) on mortality andfeeding activity of the third-instars of P.xylostella larvae. It was used a randomized complete designwith three replicates. The results showed that the leaf extract of Andropogon nardus at 8.5 % wasthe best treatment as it could caused high mortality of P. xylostella (66.67 %) and it was able todeter the feeding activity up to 82.66 %. The data suggested that extracts of Andropogon narduscontains toxic oil and feeding activity repellant.

Key words: Diamondback moth, insecticidal activity, lemon grass.