Argentine stem weevil adults (ASW, Listronotus bonariensis) feed on the leaves of agricultural grasses and their larvae mine the pseudostem, causing extensive damage that can result in plant death. Plants emit volatiles that serve as signals to host-searching insects and these odours can be altered by both herbivory and fungal endophyte-infection. This study investigated whether ASW adults utilise olfaction to identify their host plants, perennial ryegrass (Lolium perenne), and if conspecific herbivory or the presence of Epichloë festucae var. lolii fungal endophytes (strain wild-type or AR1) influenced such responses. Results from olfactometer bioassays established that ASW adults were able to utilise their olfactory response to orient towards volatiles released by perennial ryegrass and further, the weevils displayed a preference for plants previously damaged by conspecific weevils. However, there was no evidence that weevils had the ability to distinguish between endophyte-infected and endophyte-free plants using olfaction alone. Using a push–pull extraction technique, thirteen volatile compounds were identified in the blend released by perennial ryegrass. Endophyte and herbivory were found to alter these volatile compounds and quantities emitted by this forage grass. This study suggests that despite observing differences in the plant volatile blend, ASW do not perceive endophyte (wild-type and AR1) using olfaction alone and must rely on other cues, e.g. contact chemoreception or post-ingestional malaise, to detect the presence of a bioactive endophyte in an otherwise acceptable host plant.

阿根廷象鼻虫成虫（ASW，Listronotus bonariensis）以农业草的叶子为食，其幼虫挖出假茎，造成广泛的破坏，可能导致植物死亡。植物释放出挥发物，作为寄主搜索昆虫的信号，这些气味可通过食草和真菌内生菌感染而改变。这项研究调查了ASW成虫是否利用嗅觉来鉴定其寄主植物，多年生黑麦草（多年生黑麦草），以及是否为同种草食性或是否存在上蜡f。萝莉真菌内生菌（野生型或AR1菌株）影响了此类反应。嗅觉仪生物测定的结果表明，ASW成虫能够利用其嗅觉反应来应对多年生黑麦草释放的挥发物，此外，象鼻虫对先前被同种象鼻虫破坏的植物表现出了偏爱。然而，没有证据表明象鼻虫有能力单独使用嗅觉来区分被内生菌感染的植物和无内生菌的植物。使用推挽萃取技术，在多年生黑麦草释放的混合物中鉴定出13种挥发性化合物。发现内生植物和草食动物改变了这些草料中的这些挥发性化合物和排放量。这项研究表明，尽管观察到植物挥发性混合物的差异，