Bioefficacy of crude extracts of Aglaia species (Meliaceae) and some active fractions against lepidopteran larvae

Abstract

Foliar and twig extracts of three species of Aglaia were screened for larval growth inhibiting and antifeedant effects against the polyphagous lepidopteran larvae of Spodopteru lituru and Helicoverpa armigera. A . elaeagnoidea and A. odorata crude ethanolic extracts were at par in their activity at an initial treatment level of 5 mg/g of dry diet weight, while A . roxburghiana was half as active as the other two species. Detailed investigation of A . elaeagnoidea species revealed the presence of complex limonoid fractions responsible for this activity. The nutritional analyses showed impaired diet consumption and dietary utilization at 200 ppm level of treatment when limonoid fractions Fr,J and Fr,K were provided orally to S. litura larvae, indicating centrally mediated anorexic effect. The isolation of the limonoid complex from A. elueagnoidea should provide useful starting point for the development of a botanical anti-insect preparation.

Bioefficacy of flindersine against Helicoverpa armigera Hübner, Spodoptera litura Fabricius, Anopheles stephensis Liston. and Culex quinquefasciatus Say.

“…Potted cowpea plants were kept for H. armigera, and groundnut plants were provided for S. litura separately inside the adult emergence cages for egg laying. After hatching, the larvae were collected from the respective cages and fed with standard artificial diet as recommended by Koul et al (1997) for H. armigera and castor leaf for S. litura.…”

Screening for antifeedant and larvicidal activity of plant extracts against Helicoverpa armigera (Hübner), Sylepta derogata (F.) and Anopheles stephensi (Liston)

“…Initial nymphs and adults of the gram pod borer, H. armigera (Hübner) were obtained from infested Weld crops and reared in the laboratory on artificial diet prepared in the laboratory (Koul et al 1997). The cultures were maintained at 27±2°C at 16:8 L/D photoperiod.…”

Bioefficacy of Couroupita guianensis (Aubl) against Helicoverpa armigera (Hub.) (Lepidoptera: Noctuidae) larvae

“…Potted cowpea plant was kept inside adult emergence cage for egg laying. After hatching the larvae were collected from the cage and fed with standard artificial diet (Koul et al, 1997). The laboratory reared third instar larvae were used for the present investigation.…”