Abstract: Accumulated evidence shows that penetration insect attack may induce changes in host plant quality, and this will affect the normal growth and development of crops. With the change of crops resistance and insect variety, in turn, crops will cause positive or negative impact on insects. However, few studies have investigated the consequences of induced plant response due to previous insect attack on phloem-feeding insects. Herein we address whether the feeding behaviour and growth of a phloem-feeding insect are affected by host plant changes with scientific research methods using three varieties resistant wheat 98-10-30, Amigo and Batis, which are from three different countries. We measured respectively the development duration (DD), weight difference (dW) and mean relative gowth rate (MRGR) of Sitobion avenae Fab. and Schizaphis graminum (Rondani). The results showed that the aphids were either restrained or promoted when they fed on different treatment crops, compared with the control not fed by aphids and the corresponding treatment previously fed by different aphid species. S.avenae restrained the growth of S.graminum (MRGR=0.0974±0.0071) on 98-10-30, but S. graminum promoted the growth of S.avenae (MRGR=0.1614±0.0048) on 98-10-30. Penetrations of aphids promoted the growth of S. avenae on Amigo, while promoted growth of S. graminum on Batis. In addition this study suggested that the wheat variety 98-10-30 and Batis had the same resistance when no aphids fed on them. However, the variety 98-10-30 had better resistance for S. graminum, and the variety Batis had better resistance for S. avenae when they were fed by aphids. The variety Amigo had better resistance for S. graminum under all situations.

Key words: Sitobion avenae, Schizaphis graminum, induce, resistance variety, developmental duration, mean relative growth rate