Comparative Efficacy of Neem Seed Extract with Carbofuran in the Management of African Rice Gall Midge, Orseolia oryzivora Harris and Gagne (Diptera: Cecidomyppdae)

Abstract

African rice gall midge (AfRGM) Orseolia oryzivora Harris and Gagné is one of the major insect pests of rice in Africa. The dominant pest control strategy in the tropical rice over the past few decades has been in the use of synthetic insecticide. Unfortunately synthetic insecticides have not given the desired results in the management of African rice gall midge, in addition to the side effects of synthetic insecticides on the environment. In order to alleviate the growing public concerns regarding the effects of synthetic pesticides on human health and environmental impact, much attention has been given to botanicals pesticides in the recent decades. Consequently, this study was conducted to determine the efficacy of neem seed extracts in the management of AfRGM compare to carbofuran during 2006/ 2007 farming seasons at two eco-sites in Nigeria. Moreover the effect of the treatments on grain yields was carried out to determine its efficiency. Results showed that the plots treated with neem seed kernel extracts significantly (P < 0.001) reduced AfRGM damage compared to untreated check, and was not statistically different from those plots treated with synthetic pesticide across the levels and seasons. The highest infestation was recorded in the untreated control plots throughout the experimental periods. There was also significant (P < 0.05) increase in number of productive tillers in the treated plots, which significantly increased rice grain yield than in the control plots. The results therefore suggest that the application of neem seed extracts could serve as a suitable alternative to synthetic insecticides in the management of AfRGM. More so the extract has the potential to increase rice grain yield without the disruption of the agro-ecosystem.

Keyword: Plant extract, Carbofuran, Orseolia oryzivora control, grain yields