不同专化型棉蚜对寄主的选择及其机制初探

【目的】研究棉花型棉蚜和黄瓜型棉蚜依靠味觉的寄主选择行为及其机制。【方法】采用培养皿选择法探究2种专化型棉蚜的寄主选择行为;采用气相色谱-飞行时间质谱联用仪(GC-TOFMS)对棉花、黄瓜及西葫芦苗期叶片的次生化合物组分进行测定,并筛选其差异次生化合物。【结果】行为选择结果显示:棉花型棉蚜和黄瓜型棉蚜显著性地选择其原生寄主棉花和黄瓜,2种专化型棉蚜对西葫芦的选择无显著差异。次生化合物测定结果显示:棉花、黄瓜及西葫芦苗期叶片中次生化合物种类及含量存在较大差异。其中,棉花叶片中的琥珀酸和腐胺的相对含量分别为0.8006和0.1960,黄瓜叶片中对应的含量分别为0.2409和0.4401。【结论】棉蚜对寄主的选择经历了初始的嗅觉选择,完成了味觉的识别,能够反映出寄主次生化合物对棉蚜寄主选择的影响,推测次生化合物种类及含量的差异可能影响不同专化型棉蚜的寄主选择。

Host Choice of Different Host Biotypes of Cotton Aphid and Preliminary Analysis of the Mechanism

Objective] The objective of this research is to study the host choice behavior of cotton and cucumber biotype aphid depending on taste and the choice mechanism.Method] Host choice experiments of the two host biotypes were conducted by the method of Petri dish.The metabolites of cotton,cucumber and zucchini leaf in the seedling stage were measured using gas chromatography/time-of-flight mass spectrometry (GC-TOFMS) and the differential secondary compounds were selected.Result] The experiments of behavior choice showed that the two host biotypes had a significantly higher choice to their native host,respectively,and there was no significant difference to zucchini host.There was a big difference in the content of secondary compounds among cotton,cucumber and zucchini.The relative contents of succinic acid and putrescine were 0.8006 and 0.2409 in the leaves of cotton,and 0.1960 and 0.4401 in cucumber,respectively.Conclusion] The host choice of cotton aphid experienced the initial olfactory response and completed the recognition of taste,which could reflect the influence of secondary compounds to the host choice of cotton aphid.It is speculated that differential secondary compounds may influence the host choice of different host biotype aphid.