黄瓜叶信息化学物质鉴定及其对西花蓟马的行为调控

Identification of semiochemicals in cucumber leaves and their behavioral regulations on Western flower thrips Frankliniella occidentalis

[目的]本文旨在筛选对西花蓟马行为具有调控作用的黄瓜叶信息化学物质,为明确黄瓜叶片信息化学物质在西花蓟马寄主定向行为中所发挥的作用、确定该虫寄主选择的关键环境因子、筛选出专一性强的天然植物源引诱剂或趋避剂提供科学依据。[方法]利用顶空固相微萃取法提取信息化学物质,采用气相色谱-质谱联用技术,分析鉴定了黄瓜叶信息化学物质成分,应用“Y”嗅觉仪测定了西花蓟马对5种信息化学物质单体在不同浓度下的行为反应。[结果]黄瓜叶片中鉴定出的信息化学物质共有56种,可归为醛类、酮类、烷烃、酯类等13大类,包括2‐已烯醛(34.55%)、正己醛(12.73%)、顺‐3‐己烯‐1‐醇(31.64%)和苯甲醛(2.99%)等。西花蓟马对10^(-5)~10^(-1)苯甲醛、10^(-4)4‐乙基苯甲醛和10^(-2)、10^(-5)1‐戊烯‐3‐醇具有明显的正趋向反应;对10^(-5)~10^(-1)1‐己烯、10^(-2)和10^(-4)苯乙醛、10^(-1)1‐戊烯‐3‐醇和4‐乙基苯甲醛具有一定的驱避反应;对浓度为10^(-1)、10^(-3)苯乙醛和浓度为10^(-4)的1‐戊烯‐3‐醇均没有明显的趋性反应。[结论]本研究有助于阐明西花蓟马寄主选择机制,为利用天然植物源活性物质防治该害虫提供新的策略与技术途径,为实现西花蓟马高效的生物防治或生态防控奠定基础。

[Objective]The aims of this study were to screen the semiochemicals in cucumber leaves that have a regulatory effect on the behavior of Frankliniella occidentalis,to clarify the role of leaf semiochemicals in host orientation of thrips,to determine the key environmental factors of host selection,and to develop highly specific natural plant-derived attractants or repellents.[Methods]Headspace solid phase microextraction(HS-SPME)was used to extract the semiochemicals from cucumber leaves,and the semiochemicals were analyzed and identified by gas chromatography-mass spectrometry(GC-MS).The behavioral responses of thrips to five kinds of semiochemicals were determined using"Y"olfactometer.[Results]A total of 56 semiochemicals were identified in cucumber leaves,and could be classified into 13 categories,including aldehydes,ketones,alkanes and esters,etc.The major four compounds were 2-hexenal(34.55%),n-hexanal(12.73%),cis-3-hexen-1-ol(31.64%)and benzaldehyde(2.99%).Thrips showed obviously positive preference to benzaldehyde(10^(-5)~10^(-1)),4-ethylbenzaldehyde(10^(-4))and 1-penten-3-ol(10^(-2) and 10^(-5)).The repellent function was detected with 1-hexene(10^(-5)~10^(-1)),phenylacetaldehyde(10^(-2) and 10^(-4)),1-penten-3-ol(10^(-1))and 4-ethylbenzaldehyde(10^(-1)),and no obviously behavioural reaction was observed with phenylacetaldehyde(10^(-1) and 10^(-3))and 1-penten-3-ol(10^(-4)).[Conclusion]The results provided scientific support for clarifying the host-plants selection mechanism of Western flower thrips,and provided a potential thrip control strategy and technical approach using plant secondary metabolites.The study laid a foundation for the biological or ecological control against thrips efficiently.