The oviposition behavior of mosquitoes is mediated by chemical cues. In the malaria mosquito Anopheles gambiae, conspecific larvae produce infochemicals that affect this behavior. Emanations from first instar larvae proved strongly attractive to gravid females, while those from fourth instars caused oviposition deterrence, suggesting that larval developmental stage affected the oviposition choice of the female mosquito.We examined the nature of these chemicals by headspace collection of emanations of water in which larvae of different stages were developing. Four chemicals with putative effects on oviposition behavior were identified: dimethyldisulfide (DMDS) and dimethyltrisulfide (DMTS) were identified in emanations from water containing fourth instars; nonane and 2,4-pentanedione (2,4-PD) were identified in emanations from water containing both first and fourth instars. Dual-choice oviposition studies with these compounds were done in the laboratory and in semi-field experiments in Tanzania.In the laboratory, DMDS and DMTS were associated with oviposition-deterrent effects, while results with nonane and 2,4-PD were inconclusive. In further studies DMDS and DMTS evoked egg retention, while with nonane and 2,4-PD 88% and 100% of female mosquitoes, respectively, laid eggs. In dual-choice semi-field trials DMDS and DMTS caused oviposition deterrence, while nonane and 2,4-PD evoked attraction, inducing females to lay more eggs in bowls containing these compounds compared to the controls. We conclude that oviposition of An. gambiae is mediated by these four infochemicals associated with conspecific larvae, eliciting either attraction or deterrence. High levels of egg retention occurred when females were exposed to chemicals associated with fourth instar larvae.

中文翻译：

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蚊按蚊的化学介导：由与幼虫期相关的挥发物驱动的推挽系统。

蚊子的产卵行为是由化学信号介导的。在疟疾蚊子冈比亚按蚊，特定的幼虫会产生影响这种行为的信息化学物质。刚孵出的幼虫幼虫的排泄物对受孕的雌性表现出强烈的吸引力，而刚孵出的四龄幼虫的排泄物引起产卵威慑作用，这表明幼虫的发育阶段影响了雌性蚊子的产卵选择。哪个阶段的幼虫正在发育。鉴定出四种对产卵行为具有推定作用的化学物质：从含有第四龄幼虫的水中鉴定出二甲基二硫化物（DMDS）和二甲基三硫化物（DMTS）；从含有第一龄和第四龄的水体中鉴定出壬烷和2,4-戊二酮（2,4-PD）。在坦桑尼亚的实验室和半田间实验中对这些化合物进行了双选择产卵研究，在实验室中，DMDS和DMTS与产卵抑制作用相关，而壬烷和2,4-PD的结果尚无定论。在进一步的研究中，DMDS和DMTS引起卵存留，而壬烷和2,4-PD分别引起88％和100％的雌性蚊子产卵。在双选择半田试验中，DMDS和DMTS引起了产卵抑制，而壬烷和2,4-PD引起了吸引力，与对照相比，诱使雌性在含有这些化合物的碗中产卵更多。我们得出结论，在进一步的研究中，DMDS和DMTS引起卵存留，而壬烷和2,4-PD分别引起88％和100％的雌性蚊子产卵。在双选择半田试验中，DMDS和DMTS引起了产卵威慑，而壬烷和2,4-PD引起了吸引力，与对照相比，诱使雌性在含有这些化合物的碗中产卵更多。我们得出结论，在进一步的研究中，DMDS和DMTS引起卵存留，而壬烷和2,4-PD分别引起88％和100％的雌性蚊子产卵。在双选择半田试验中，DMDS和DMTS引起了产卵抑制，而壬烷和2,4-PD引起了吸引力，与对照相比，诱使雌性在含有这些化合物的碗中产卵更多。我们得出结论，一个。冈比亚是由与特定幼虫相关的这四种信息化学物质介导的，可引起吸引力或威慑作用。当雌性接触与第四龄幼虫有关的化学物质时，卵子的保留率很高。