Fateme Najafi - MSc study of agricultural entomology, university of Mohaghegh Ardabili
Jabraeil Razmjou - Assoc. Prof. of plant protection, collage of agriculture, university of Mohaghegh Ardabili.
Mahdi Hassanpour - Assistant professor of plant protection department, University of Mohaghegh Ardabili, Ardabil.
Ali Golizadeh - Assistant professor of plant protection department, University of Mohaghegh Ardabili, Ardabil

The green aphid Schizaphis graminum Rondani is one of the main pests of cereal in different areas ofworld that causes decrease crop by sucking juice wheat and transmitting viruses such as barley dwarfyellow mosaic, cane mosaic and maize dwarf mosaic. This study was carried out in order to searching forthe effect of some wheat lines on biological characteristics of green aphid and recognize some resistantlines. First, the screening test was conducted and forty lines of wheat infected by the aphids were obtainedfrom agricultural faculty of Tarbiat Modarres University. Fourteen days after initial infection, all ofproduced aphids on each seedling were counted and registered and then ten wheat lines as relativelyresistant, partially resistant and susceptible lines were selected for further evaluations. Also, Aphidbiological characteristics on selected lines were studied. The results showed that the percentage survivalof nymphs from 48 to 92 percent on Sarasari 88-19 and Sarasari 88-14 lines, respectively, is variable. Thehighest and lowest immature time of aphid were observed on lines of Sarasari 87-9 (7 day) and Sarasari88-7 (6 day). The highest and lowest mean number of nymphs produced by each mature was on lines ofSarasari 88-8 (60.36) and Sarasari 87-8 (34.68). The highest and lowest longevity and reproduction periodof matures were on lines of Sarasari 88-3 and Sarasari 88-19.The results of this study indicate that twowheat lines (Sarasari 88-19 and Sarasari 87-8) are relatively resistant against this pest and these can beused in integrated pest control programs.

green aphid, lines of wheat, biological characteristics