Comparative Efficacy of Phytopesticides in the Management of Podagrica spp and Mosaic Disease on Okra (Abelmoschus esculentus L.)

Abstract

Aims: To evaluate the effectiveness of different aqueous plant extracts on the management of flea beetles (Podagrica spp) and mosaic disease on okra Study Design: The treatments applied were 10% (w/v) crude extract each of neem leaf, garlic, mahogany bark, chili pepper fruit, pawpaw leaf, bougainvillea leaf and the control (water), laid out in a Randomized Complete Block Design with four replications Place and Duration of Study: School of Agriculture Teaching and Research Farm, University of Cape Coast, Ghana during the 2012 crop season. Methodology: The treatments were applied weekly starting 21 days after sowing. Data was taken on the population of Podagrica species, severity of pest damage, incidence and severity of okra mosaic disease. Data was subjected to analysis of variance and means separated with least significant difference. Results: All the phytopesticides significantly reduced the flea beetle populations and the corresponding pest damage on the okra plants than the control (P=0.05). However, neem leaf and garlic extracts were significantly better than the other phytopesticides in reducing the pest population and the pest damage (P=0.05) resulting in the highest fruit yield. Incidence and severity of the okra mosaic disease were significantly kept under control by the neem, garlic and bougainvillea extracts as compared to the other treatments. Population of the flea beetle was positively and significantly correlated with pest damage (r=0.821; P=0.05), and severity of okra mosaic disease (r=0.786; P=0.05) but negatively correlated with fruit yield (r=-0.750; P=0.05). Fruit yield was also negatively and highly correlated with pest damage (r=-0.857; P=0.05) and the severity of okra mosaic disease (r=-0.821; P=0.05). Conclusion: Neem leaf and garlic extracts were effective in reducing flea beetle infestation and okra mosaic disease infection, resulting in high fruit yield in okra.