[Effects of wheat leaf surface waxes on the feeding of two wheat aphid species]

By using GC-MS and bioassay techniques, this paper studied the effects of different wheat varieties (cultivars) leaf surface waxes on the feeding of wheat aphids Sitobion avenae and Rhopalosiphum padi. The results showed that the leaf surface waxes of wheat varieties (cultivars) SN80, SN18 and Zimail2 could stimulate the feeding of test aphids, while SN87 could not. GC-MS analysis showed that the chemical composition of leaf surface waxes differed with wheat varieties (cultivars). The main components were long chain alkanes, and others were 7-tetradecene, 8-pentadecanone, ethyl citrate, tetradecanoic acid ethyl ester, and hexadecanoic acid ethyl ester. The bioassay found that alkanes (> C17), 7-tetradecene and 8-pentadecanone could act as strong stimulants to the feeding of the aphids, while ethyl citrate, tetradecanoic acid ethyl ester and hexadecanoic acid ethyl ester didn't have stimulation to S. avenae, neither tetradecanoic acid ethyl ester and hexadecanoic acid ethyl ester to R. padi.