Evaluation of Certain Botanical Extracts and Synthetic Insecticides against Whitefly, Bemisia tabaci (Gennadius) and Cotton Aphid, Aphis gossypii L. on Cucumber (Cucumis sativus L.) under Field Condition

Abstract

Screening extracts of wild plant species for insecticidal properties might lead to the discovery of new agents of pests management. The aim of this study was to evaluate insecticidal efficiency of five plant extracts in comparing with three synthetic insecticides against white fly, Bemisia tabaci and cotton aphid, Aphis gossypii infesting cucumber plants. The study was conducted at Nobaria district, Beheira Governorate, Egypt during two successive summer seasons of 2020 and 2021 under the open field conditions. The tested botanical extracts included aloe, Aloe barbadensis; oleander, Nerium oleander; ginger, Zingiber officinale; garlic, Allium sativum and chinaberry, Melia azedarach. The results showed that these extracts had potential effects in reducing the population density of B. tabaci and A. gossypii on cucumber plants. The descending order of plant extracts efficacy against B.tabaci nymphs treated with 10 % (w/v) was chinaberry followed by oleander, garlic, aloe and ginger. On the other hand, the efficiency of the tested plant extracts on the cotton aphids could be arranged according to their percentages of reduction in infestation as following: chinaberry, oleander, aloe, garlic and Ginger. According the provided data we can conclude that the tested aqueous extracts have an insecticidal effect against B. tabaci and A. gossypii and can be integrated into their management strategies. However, this inference needs thorough testing before generalization.