Abstract: The behavior of Sitobion miscanthi (Takahashi) on 15 different tolerant varieties was observed and the antixenosis and antibiosis of these wheat varieties in seedling were tested by using aphids confinement test. Selected five characteristic varieties, we recorded the fecundity of aphids in field during anthesis, assayed the content of quercetin and tannin in flag leave and ear, and detected the activity of carboxylesterase (CarE) and glutathione S transferase (GST) of the aphids on these varieties. The results indicated the effects of the five selected wheat varieties in seedling and anthesis on the fecundity of aphids were significantly positively correlated (r= 0.956*). The correlation between quercetin in ear of wheat and the fecundity of aphids on different wheat varieties was significantly negative (r=-0.941*). The tannin contents of different wheat varieties were significantly different, but showed no significant correlation with the fecundity of aphids. The contents of carboxylesterase (CarE) and glutathione S-transferase (GST) of aphids feeding on different wheat varieties were significantly different. We concluded that different varieties had strong inhibiting effects on the fecundity of S. miscanthi, especially with the effects of Zhong 4 wumang and Jibao No.1 stronger.

Key words: Sitobion miscanthi, wheat variety, antibiosis, allelochemicals, carboxylesterase glutathione S-transferase