Effect of Neem Seed Kernel Extracts in the Management of Rice Stem Borers in the Field in Nigeria

Abstract

Stem borers are economic pests of rice and its management through conventional methods has not given the desired results. Hence in this study field experiments were conducted to determine the comparative efficacy of neem seed kernel extracts (Azadirachta indica; (Neem) and synthetic insecticide (Carbofuradan) against rice stem borers in Nigeria during 2006/07 farming season. The effect of these sprayings was also recorded on natural enemies and yield attributes. Results showed that the two pesticides significantly (p < 0.01) reduced stem borers damage (number of dead hearts, white heads) compared to untreated check, and also significantly (p < 0.05) increased number of productive tillers with resultant increase in grain yield than the control plots. Maximum numbers of different natural enemies were found in neem extract treated plots against the carbofuran treated plots. It is suggested that on the basis of infestation of borer, high yield and conservation of natural enemies, neem seed extract can be regarded as suitable alternative to synthetic insecticides for the management of rice stem borers in the field.

Keywords: Botanical/insecticide, stem borer control

Nig J. Biotech. Vol. 23 (2011) 13- 21