Role of Nozzle Types and Certain Adjuvants in Reducing Application Rates of Imidacloprid; Spirotetramat Against Whitefly, Bemisia tabaci (Gennadius) on Zucchini Plant

In Egypt, zucchini squash, Cucurbita pepo L., is an important vegetable. Whitefly, Bemisia tabaci (Gennadius), has massively infested them. The insect has causes damage by sucking sap or spreading viruses, and it can considerably reduce yield. The widespread usage of traditional insecticides has resulted in a comeback of insecticide resistance. The current study examined the role of the nozzle type (cone nozzle Tx-6, flat fan Ss083), with two adjuvants (Argal (Silwet 408), and Techno oil) in the effectiveness of imidacloprid, and spirotetramat insecticides. Therefore, the recommended dose of these insecticides alone was compared to the recommended dose + adjuvants, 3/4 recommended dose + adjuvants, and half recommended dose + adjuvants. The obtained data showed that imidacloprid was superior to spirotetramat. On the other hand, there was no significant difference between the nozzles used. In addition, adjuvants played an essential role in increasing the insecticides' effectiveness. Compared to insecticide alone, the adjuvant increased the efficacy of the insecticides when added to the recommended dose, and the 3/4 recommended dose of the insecticide. Additionally, adding Argal to the spray tank mixtures was more productive than adding Techno oil. The recommended dose of the target insecticides could be reduced, and the same effect is maintained through the optimal application method, with using adjuvants.