香蕉假茎象甲对不同生理状态香蕉假茎挥发物的行为反应

采用固相微萃取技术提取新鲜假茎、腐烂未虫蛀假茎、虫蛀且腐烂假茎以及虫蛀未腐烂假茎4种生理状态的香蕉假茎挥发物,进行气质联用仪分析鉴定。结果表明:从香蕉新鲜假茎与虫蛀且腐烂假茎中分别鉴定出10种挥发性物质;腐烂未虫蛀假茎与虫蛀未腐烂假茎分别鉴定出11种挥发性物质;这些挥发物包括烃类、酯类、酮类、杂环类等,在不同生理状态的香蕉假茎中的相对含量各不相同。4种生理状态的香蕉假茎挥发性成分种类数及相对含量的变化与香蕉假茎象甲Odoiporus longicollis Olivier的为害有着密切关系,遭受香蕉徦茎象甲为害的香蕉假茎,其共同成分2,6-二甲基-2,4,6-辛三烯相对含量对应地减少。利用双重陷阱嗅觉仪测定了香蕉假茎象甲对香蕉假茎挥发物的行为反应,结果表明:4种生理状态的香蕉假茎挥发物均对香蕉假茎象甲有引诱作用,与新鲜假茎相比,香蕉假茎的虫蛀且腐烂状态可增强其对香蕉假茎象甲雌、雄虫的引诱作用。

Study of the behavioral responses of Odoiporus longicollis to volatiles from banana pseudostems with different physiological status

Solid phase microextraction （SPME） was used to extract volatiles from banana pseudostems in the following four physiological states：fresh, rotten but not fed on by beetles, rotten and fed on by beetles, and fresh and fed on by beetles. The extracted volatiles were analyzed by gas chromatography-mass spectrometry （GC-MS）. A total of 10 components were identified from volatiles extracted from fresh and rotten pseudostems that had been fed on by beetles, whereas a total of 11 components were identified from extracts from rotten pseudostems and fresh pseudostems that had been fed on by beetles. The extracted volatiles included hydrocarbon, esters, ketone and heterocyclic compounds, the relative abundance of which differed with pseudostems＇ physiological state. The species and relative abundance of extracted volatiles were closely related to damage inflicted by the banana pseudostem weevil. There was a corresponding reduction in the relative content of the common component allo-ocimene after Odoiporus longicollis Olivier infestation. The behavioral responses of male and female O. longicollis to extracted volatiles from banana pseudostems in each of the four physiological states were observed with a double pitfall olfactometer. Both male and female O. longicollis were attracted to the volatiles from banana pseudostems in different physiological states. Compared to fresh pseudostems, beetle feeding activity and rottenness enhanced the attractiveness of the extracted volatiles from banana pseudostems to male and female O. longicollis.