中文摘要：

【目的】研究不同抗性水平的小麦品种苗期对麦长管蚜的抗蚜机制。【方法】用EPG技术对麦长管蚜在3个小麦品种苗期的取食行为进行检测。【结果】麦长管蚜在品种Ww2730上口针开始接触叶面时间显著晚于小偃22和Batis,第1次持续刺探前的刺探次数显著多于小偃22和Batis,开始刺入叶面后第1次刺探的持续时间极显著短于小偃22和Batis;在Ww2730和小偃22上的PdⅡ-1的平均时间显著长于Batis;Ww2730上C波阶段2个Pd波间的间隔平均时间显著大于另外2个品种;在Ww2730木质部取食（G波）的次数和时间显著大于其它2个品种;Batis上的点G波的次数极显著地高于Ww2730,而平均持续时间极显著短于小偃22和Ww2730;在Batis和小偃22上E1波的总时间,E1波的最大值、跟随E2波的E1波的平均时间均显著大于Ww2730;3个品种间第1次E1波持续的时间差异不显著,但Ww2730和小偃22上其它E1波持续的时间极显著少于Batis;3个品种上其它波形参数,包括F波的次数和总时间、E2波的次数和总时间没有差异。【结论】Ww2730抗麦长管蚜机制可能在于表皮有取食抑制因子,叶肉细胞壁较厚,韧皮部存在次生物质和（或）营养不平衡。小偃22苗期的抗蚜机制为叶肉部细胞壁较厚,细胞密度大。麦长管蚜适应Ww2730抗性的策略可能是在第2次取食时采取了减少在有毒次生物中的暴露时间。

英文摘要：

[ Objective ] The objective of the study was to study the potential resistance mechanism of three different wheat varieties at seedling stage to S. avenae. [ Method] Aphid feeding behaviors had been ascertained using EPG technique. [Result.] When the aphids were feeding on Ww2730 seedlings, the time to 1 st probing was delayed compared to those on Xiaoyan22 and Batis, searching was interrupted before 1 st probing, and 1 st probing was shorter than that on Xiaoyan22 and Batis significantly. Duration of pd Ⅱ-1 on Ww2730 and Xiaoyan22 was much longer than that on Batis. Duration of pd in C waveforms on Ww2730 was ionger than that on Xiaoyan22 and Batis remarkedly. Times and duration of G waveform （ingestion in xylem） on Ww2730 were more and longer. Times of spot G waveform on Batis were more than on Ww2730 significantly, but the duration was shorter than those on Xiaoyan22 and Ww2730. Total time of E1 waveform, max longest duration of E1 fractions and mean duration time of E1 fractions following E2 wavefrom on Xiaoyan22 and Batis were all longer than on Ww2730 statistically. There were no differenences among mean durations of 1 st E 1 wavefrom on three varieties, but mean durations of other E 1 waveforms on Ww2730 and Xiaoyan22 were shorter than those on Batis. The other waveform parameters, include times and durations of F and E2 were all not different on three wheat varieties. [ Conclusion ] It is suggested that the resistance mechanism of wheat variety Ww2730 to S. avenae is a restriction factor of aphid feeding in epidermis, thicker cell wall in mesophyll and secondary metabolites or nutrition unbalance in phloem in seedling phase of the wheat. Resistance mechanism of Xiaoyan22 is thicker cell wall and more cell layer in mesophyll in seedling phase. The feeding strategy of S. avenae against the resistance of Ww2730 was shortening the second duration of secreting watery salivation to xylem compared to the first.