BIOLOGICAL AND CONTROL STUDIES ON RHOPALOSIPHUM PADI INFESTING WHEAT PLANTS, TRITICUM AESTIVUM AT MENOUFIA GOVERNORATE, EGYPT

Seasonal fluctuations of wheat aphid, Rhopalosiphum padi L., infesting five wheat varieties, were investigated under field conditions along 2020/2021 season at Menoufia governorate, as well as, biological and biocontrol studies on this pest were conducted, moreover, residual of pesticides were determined in seeds, straw and soil of treated wheat plants. As for the population density of R. padi, the highest numbers were recorded in March 2021 on Gemiza 11 variety. The life cycle of R. padi lasts 10.6 days ± 0.5 , the adult viviparous female lived 12.2 ± 0.4 days spends two days without putting larvae, put 28.4 ± 1.3 individuals during the reproductive period (10.2± 0.4) days, the life span lasts 20.8 ± 0.8 days. Abamectin 3.6 % EC (double dose) and Congest 15% SC were effective in reducing the number of aphids per leaf, recording 46.67100% reduction and recording residues in wheat straw and wheat seeds less than the maximum residues limits. The tested treatments did not affect the germination process. The tested bio agents as nonconventional insecticide could be considered suitable for aphid control and safe for human and environment. It could be recommended the use of Abamectin and Imidacloprid in integrated aphid management programs.