Lubanga Umar K, Drijfhout Falko P, Farnier Kevin, Steinbauer Martin J
Department of Ecology, Environment & Evolution, La Trobe University, Melbourne, Victoria, 3086, Australia.
Chemical Ecology Group, Keele University, Keele, UK.
J Chem Ecol. 2016 Feb;42(2):163-72. doi: 10.1007/s10886-016-0674-2. Epub 2016 Feb 27.
Mating is preceded by a series of interdependent events that can be broadly categorized into searching and courtship. Long-range signals convey species- and sex-specific information during searching, while short-range signals provide information specific to individuals during courtship. Studies have shown that cuticular hydrocarbons (CHCs) can be used for mate recognition in addition to protecting insects from desiccation. In Psylloidea, four species rely on semiochemicals for long-range mate attraction. Psyllid mating research has focused on long-range mate attraction and has largely ignored the potential use of cuticular hydrocarbons (CHCs) as mate recognition cues. This study investigated whether CHCs of Aacanthocnema dobsoni have semiochemical activity for long- and short-range communication prior to mating. Using a solid sampler for solvent-less injection of whole psyllids into coupled gas chromatography/mass spectrometry, we found quantitative, sex- and age-related differences in CHC profiles. Males had higher proportions of 2-MeC28, 11,15-diMeC29, and n-C33 alkanes, while females had higher proportions of 5-MeC27, 3-MeC27, 5,15-diMeC27, n-C29 and n-C30 alkanes. In males and females, 84 and 68 % of CHCs varied with age, respectively. Y-tube olfactometer bioassays provided no evidence that males or females responded to odors emanating from groups of conspecifics of the opposite sex. Tests of male and female psyllids for attraction to branchlets previously occupied by conspecifics showed no evidence of attraction to possible semiochemical residues. Our short-range chemoreception bioassay showed that males were as indifferent to freshly killed individuals of either sex with intact CHC profiles as to those treated with hexane (to remove CHCs). Aacanthocnema dobsoni utilizes substrate-borne vibrations (SBVs) for communication. Therefore, our results indicate that SBVs are probably more important than semiochemicals for long-range mate attraction. Furthermore, CHCs are unlikely to mediate short-range mate recognition or provide mate assessment cues.
交配之前会发生一系列相互依存的事件，这些事件大致可分为搜索和求偶。在搜索过程中，远距离信号传达物种和性别特异性信息，而近距离信号在求偶过程中提供个体特异性信息。研究表明，表皮碳氢化合物（CHCs）除了能保护昆虫免受干燥影响外，还可用于配偶识别。在木虱总科中，有四个物种依靠信息化学物质进行远距离配偶吸引。木虱交配研究主要集中在远距离配偶吸引上，很大程度上忽略了表皮碳氢化合物（CHCs）作为配偶识别线索的潜在用途。本研究调查了多氏棘木虱的CHCs在交配前的远距离和近距离通讯中是否具有信息化学活性。使用固体采样器将整个木虱无溶剂注入气相色谱/质谱联用仪，我们发现CHC谱存在数量、性别和年龄相关差异。雄性中2-甲基二十八烷、11,15-二甲基二十九烷和正三十三烷的比例较高，而雌性中5-甲基二十七烷、3-甲基二十七烷、5,15-二甲基二十七烷、正二十九烷和正三十烷的比例较高。在雄性和雌性中，分别有84%和68%的CHCs随年龄变化。Y型管嗅觉仪生物测定未提供证据表明雄性或雌性对来自异性同种群体散发的气味有反应。对雄性和雌性木虱对先前被同种个体占据的小枝的吸引力测试未显示对可能的信息化学残留有吸引力的证据。我们的近距离化学感受生物测定表明，雄性对具有完整CHC谱的新鲜杀死的两性个体与用己烷处理过的个体（去除CHCs）同样无动于衷。多氏棘木虱利用底物传播振动（SBVs）进行通讯。因此，我们的结果表明，对于远距离配偶吸引，SBVs可能比信息化学物质更重要。此外，CHCs不太可能介导近距离配偶识别或提供配偶评估线索。
