Abstract: Using the two cultivars(Kexin No. 1 and Feiwuruita)of potato,as the experimental material,the interaction between peach aphid and potato was studied under applying potassium condition.The tendency of peach aphid to potassium application and control plants was determined by using the Y-type olfactometer.The results showed that the trend rate of aphid to Feiwuruita was 26% for potassium application and 71% for control plants and that of Kexin No. 1 was 30% and 64%,respectively.Based on the study above,the main volatile content of two potato cultivars was studied by TCT-GC-MS technique under different potassium application conditions. The results indicated that there were four main compounds including in 3-arene,benzaldehyde,limonene and 1,3-cyclohexadiene varying greatly in the two potato cultivars.The four kinds of volatiles contents were significantly higher than those of the control at the dose of 6 g/plant potassium sulphate in the leaves of Kexin No.1,and limonene content was the highest,reaching 2.5 times of the control. However,only benzaldehyde content in Feiwuruita plants was significantly higher than that in the control.The content of jasmonic acid and activity of lipoxygenase(LOX) in potato were determined by liquid-mass technique and colorimetry respectively.It was found that the jasmonic acid content of Kexin No.1 leaves was 0.93 times higher than the control,and LOX enzyme activity was 0.4 times higher after 6 g/plant potassium application.iTRAQ further demonstrated that 6 g/plant potassium application increased the protein expression of LOX.Overall,6 g/plant application of potassium is the optimal amount of potassium fertilizer for the aphid resistance of potato.

Key words: Potassium fertilizer, Solanum tuberosum, Peach aphid, Trend rate, Jasmonic acid, Volatile substance

摘要： 为了解施钾条件下桃蚜—马铃薯相互作用关系，以马铃薯克新1号和费乌瑞它为试验材料，通过“Y”型嗅觉仪测定桃蚜对施钾后2个马铃薯品种的趋性行为。结果表明，桃蚜对克新1号对照（未施钾）和施钾植株的趋向率分别为64%、30%，对费乌瑞它对照和施钾植株趋向率分别为71%、26%。采用TCT-GC-MS（热脱附-气相色谱-质谱）测定不同施钾量2个马铃薯品种中主要挥发物含量的结果表明，主要挥发物有4种：3-蒈烯、苯甲醛、柠檬烯和1，3-环己二烯。其中，6 g/株施钾量使克新1号叶片中上述4种挥发物含量显著高于对照，柠檬烯含量达到最高，是对照的2.5倍；而费乌瑞它叶片中只有苯甲醛含量显著高于对照。用液质联用技术和比色法分别测定马铃薯克新1号叶片中茉莉酸含量和脂氧合酶（LOX）活性的结果表明，6 g/株施钾量使马铃薯克新1号叶片中茉莉酸含量比对照提高0.93倍，LOX活性提高0.40倍。iTRAQ技术（同位素相对标记与绝对定量技术）进一步证明，6 g/株施钾量上调了克新1号叶片LOX蛋白表达量。综上，马铃薯抗桃蚜的最佳施钾量为6 g/株。

关键词: 钾肥, 马铃薯, 桃蚜, 趋向率, 茉莉酸, 挥发物