Abstract: 【Aim】To clarify the resistance differences of four wolfberry varieties to Aphis gossypii， so as to ascertain the anti-aphid factor and insect resistance site, and select the aphid-resistant wolfberry varieties. 【Methods】Electrical penetration graph technology (EPG) was used to record the feeding behaviors of A. gossypii adults on four wolfberry varieties (Ningqi No.1, Ningqi No.5, Ningqi No.7 and Ningqi No.10), and the indoor aphid resistance identification combined with cluster analysis was used to comprehensively evaluate the resistance of different wolfberry varieties to A. gossypii adults. 【Results】A. gossypii adults feeding on four wolfberry varieties showed eight kinds of waveforms, including Np, A, G, B, C, Pd, E and F waveforms. During the feeding of A. gossypii adults, the duration of E1 waveform on Ningqi No.1 was the longest, followed by that on Ningqi No.5 and Ningqi No.7, and that on Ningqi No.10 was the shortest. The duration of E2 waveform on Ningqi No.10 was the longest, and that on Ningqi No.1 was the shortest. The duration of F waveform on Ningqi No.1 was the longest, that on Ningqi No.10 was the shortest, and that on Ningqi 5 and Ningqi 7 was that between on Ningqi No.1 and on Ningqi No.10, suggesting that Ningqi No.1 has strong mechanical resistance and Ningqi No.10 has weak mechanical resistance. Through identification of aphid resistance and cluster analysis, four wolfberry varieties were classified into 3 categories: Ningqi No.1 in category Ⅰ was a highly aphid-resistant variety, Ningqi No.5 and Ningqi No.7 in category Ⅱ were aphid-resistant varieties, and Ningqi No.10 in category Ⅲ was a aphid-susceptible variety. 【Conclusion】The feeding behaviors of A. gossypii adults on four wolfberry varieties are different, and there are differences in the insect resistance mechanism and resistance site in the four wolberry varieties. The wolfberry variety Ningqi No.1 shows resistance to A. gossypii adults at the levels of leaf epidermis, mesophyll and phloem, with the strongest aphid resistance, and is a highly aphid-resistant variety. Ningqi No.5 and Ningqi No.7 show resistance to A. gossypii adults at the levels of mesophyll and phloem, with weak aphid resistance, and are aphid-resistant varieties. A. gossypii adults can sting and fed for a long time on Ningqi No.10, which shows the weakest resistance to A. gossypii adults and is a aphid-susceptible variety.

Key words: Aphis gossypii, wolfberry, feeding behavior, cultivar selection, aphid resistance, electrical penetration graph