Insect Pests Control of Okra (Abelmoschus esculentus) by Using Plant Aqueous Extracts in Korhogo Area (Northern Côte d’Ivoire, West Africa)

Abstract

In this study, we monitored for the impact of three aqueous extracts of plants (Azadirachta indica, Hyptis suaveolens and Solanum lycopersicum) on insect pests abundance in okra (Albermochus esculentus L.) crop, compared to a synthetic chemical « SAUVEUR 62 EC », having as active ingredients, acetamiprid 32g/l and Lambda-cyhalothrin 30g/l. Foliar applications by these extracts were done using manual sprayers. After treatment, the insects were caught using two methods (pitfall traps and colored bowls traps). A total of 6505 insects belonging to nine orders were recorded in four plots. The plot 1 (9 orders) was the most diverse, followed by the plot 3 (8 orders), the plot 2 and 4 (7 orders respectively). Coleoptera, Lepidoptera, Diptera, Orthoptera and Hemiptera were the most frequents. The chemical treatment has impacted significantly the number of orders (p < 0.05) but, the insect abundance was impacted significantly by the different biological treatments (p < 0.05). This study showed that the aqueous extract of Solanum lycopercicum was more effective on the abundance of pests belonging to Hemiptera, while the aqueous extracts of Azadirachta indica and Hyptis suaveolens were effectives on the abundance of pests belonging to Coleoptera. The chemical treatment was effective on the pests belonging to both orders.