Antennal olfactory receptor neurons (ORNs) for pheromone-related and plant volatile compounds were identified and characterized in the lucerne weevil, Sitona discoideus (Gyllenhal), using the single sensillum recording technique. Our study using five pheromone-related compounds and 42 plant volatile compounds indicates that S. discoideus have highly specialized ORNs for pheromone and plant volatile compounds. Different groups of ORNs present in both males and females of S. discoideus were highly sensitive to 4-methylheptane-3,5-dione (diketone) and four isomers (RR, RS, SR and SS) of 5-hydroxy-4-methylheptan-3-one, respectively. Our results also indicate that male S. discoideus, using the sensory input from antennal ORNs, can distinguish both diketone and the RR-isomer from others, and RS- and SS-isomers from others, although it was unclear if they can distinguish between RS-isomer and SS-isomer, or between diketone and the SR-isomer. It also appeared that female S. discoideus could distinguish between RS-isomer and SS-isomers. The antennae of S. discoideus thus contain sex-specific sets of ORNs for host- and non-host plant volatile compounds. Both sexes of S. discoideus have highly sensitive and selective ORNs for some green-leaf volatiles, such as (Z)-3-hexenol and (E)-2-hexenal. In contrast, male antennae of S. discoideus house three distinct groups of ORNs specialized for myrcene and (E)-β-ocimene, 2-phenylethanol, and phenylacetaldehyde, respectively, whereas female antennae contain three groups of ORNs specialized for (±)-linalool and (±)-α-terpineol, myrcene and (E)-β-ocimene, (±)-1-octen-3-ol, and 3-octanone. Our results suggest that S. discoideus use a multi-component pheromone communication system, and a sex-specific set of ORNs with a narrow range of response spectra for host-plant location.

中文翻译：

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嗅觉受体神经元的植物挥发物和信息素化合物在卢塞恩象鼻虫，Sitona discoideus。

使用单sensillum记录技术，在卢塞恩象鼻虫（Sitona discoideus）（Gyllenhal）中鉴定并鉴定了信息素相关和植物挥发性化合物的嗅觉嗅觉神经元（ORN）。使用五个信息素有关的化合物和42个植物挥发性化合物，我们的研究表明，S. discoideus已经高度专业化的信息素和植物挥发物ORNs。ORNs存在于男性和女性的不同组S. discoideus分别以4-甲基庚烷-3,5-二酮（二酮）和四种异构体（高度敏感的RR，RS，SR和SS）分别为5-羟基-4-甲基庚基-3-一）。我们的研究结果还表明，男性S. discoideus，利用触角ORNs感官输入，可以区分两者二酮和RR从其他异构体，以及RS -和SS从别人-异构体，虽然目前还不清楚他们是否可以区分RS -异构体和SS-异构体之间，或在二酮和SR-异构体之间。还似乎雌性盘状链球菌可以区分RS-异构体和SS-异构体。盘状链球菌的触角因此含有针对宿主和非宿主植物挥发性化合物的性别特定的ORN集。的两性S. discoideus有一些绿叶挥发物高灵敏度和选择性ORNs，如（ż）-3-己烯醇和（Ë）-2-己烯醛。与此相反，雄性触角S. discoideus房子ORNs的三个不同的组专用于月桂烯和（Ë分别）-β-罗勒烯，2-苯基乙醇，苯乙醛和，而雌性触角包含三组专用于（±）ORNs的-芳樟醇和（±）-α-松油醇，月桂烯和（E）-β-烯丙基，（±）-1-辛烯-3-醇和3-辛酮。我们的结果表明，盘状链球菌 使用多成分信息素通讯系统和一组针对性别的ORN，这些ORN的响应光谱范围狭窄，可用于寄主植物的定位。