Effect of Weather Change and Plant Age on the Whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) on Tomato Plants and its Control in Dakhlia Region, Egypt

This experiment was carried out in two consecutive seasons (2022/2023 and 2023/2024) at Mansoura district of the Dakhlia Governorate, Egypt, to investigate population of the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) on tomato plants (Fiona cultivar) and its relation to certain climate parameters. Data showed that 30 days from planting, or from the first week of October to the fourth week of January in both seasons, B. tabaci was found on tomato plants. Between the two seasons, the total counts of B. tabaci were 138.15 and 154.08 individuals per season, respectively. Over the course of the two seasons, the average number of B. tabaci per leaf was 8.63 and 9.63 individuals, respectivelyStatistically, the multiple linear regression method exhibited that the pooled impact of all climate parameters and plant age, reached 95.45% in 2022/2023 and 93.05 % in 2023/2024 on the variation in B. tabaci populations. However, these effects reached 97.77% in 2022/2023 and 94.39% in 2023/2024 on the percentage of damaged leaves.The activities of the tested insecticides varied, as it was exhibit that Cyantraniliprole was take place to be the most susceptible insecticide than the other tested pesticides on B. tabaci nymphs and adult females after 72 hours. While Azadirachtin pesticide was less toxic. Using the results of this study, whitefly populations on tomato plants can be effectively managed and the damage they cause can be reduced.