椰心叶甲对植物挥发化合物的触角电位与行为反应

Electrophysiological and behavioral responses of Brontispa longissima to plant volatile compounds

椰心叶甲[Brontispa longissima (Gestro)]聚集潜藏于寄主未展开的心叶中取食危害,药剂难于接触虫体成为该害虫防治的重要瓶颈。为了应用有刺激气味的植物挥发化合物,胁迫椰心叶甲逃出心叶而暴露,以触角电位技术和行为生测,筛选出对椰心叶甲有较强胁迫驱避作用的化合物。结果表明:9种植物挥发化合物中,椰心叶甲雌、雄成虫触角对肉桂醛电位反应最强,触角电位相对反应值分别达到了128.17±0.44和103.87±2.54;芳樟醇、α-蒎烯、薄荷脑电位反应较弱,触角电位相对反应值分别为33.28±1.18和15.95±0.91、31.90±0.69和16.86±0.33、32.90±1.60和14.55±0.51。除了松节油和1-庚醛,其余化合物刺激雌虫触角产生的电位相对反应值均显著大于雄虫。椰心叶甲雌、雄成虫触角电位相对反应值与肉桂醛的浓度呈正相关。行为生测发现,稀释5×104倍液以下的肉桂醛对椰心叶甲雌、雄成虫均有显著的驱避作用,且浓度越高,椰心叶甲定向反应率越高。在稀释1×102倍液时,驱避率分别达到了72.41%±3.16%和70.22%±3.22%,可见,肉桂醛对椰心叶甲成虫有较强刺激和胁迫作用。

Brontispa longissima(Gestro)congregates in the unfolded heart leaves of palm plants;therefore,it is difficult to control the pest because the pesticide cannot enter and contact the pest.In this paper,antennal potential technology and behavioral bioassays were used to screen compounds that exert strong stress on B.longissima,thereby forcing B.longissima to leave the heart leaves and expose them to the stimulating volatile plant compound odors.The results showed that the adult antennae had the strongest response to cinnamaldehyde among the 9 volatile compounds tested,with the relative reaction values of the electroantennogram reaching 128.17±0.44 and 103.87±2.54.The lowest potential occurred for linalool,α-pinene,and menthol with relative reaction values of the electroantennogram reaching 33.28±1.18 and 15.95±0.91,31.90±0.69 and 16.86±0.33,and 32.90±1.60 and 14.55±0.51,respectively.Except for turpentine and 1-heptenal,the relative reaction values of the electroantennogram produced by the rest of the compounds with the antennae of females were significantly greater than those of males.There was a positive correlation between the relative reaction values of the electroantennogram and the concentration of cinnamaldehyde for adult B.longissima.The behavioral bioassay showed that cinnamaldehyde that was diluted less than 5×104 times significantly repelled adult B.longissima,and the higher concentration corresponded with a higher rate of the targeted response.When diluted 1×102 times,the repellent rate reached 72.41%±3.16%and 70.22%±3.22%.Thus,it can be seen that cinnamaldehyde had the strongest stimulatory and stress effects on adult B.longissima of the 9 compounds tested.