Data for: Nectar-dwelling microbes of common tansy are attractive to its mosquito pollinator, Culex pipiens

AbstractThere is widespread interkingdom signalling between insects and microbes. For example, microbes found in floral nectar may modify its nutritional composition and produce odorants that alter the floral odor bouquet which may attract insect pollinators. Mosquitoes consume nectar and can pollinate flowers. We identified microbes isolated from nectar of common tansy, Tanacetum vulgare , identified the microbial odorants, and tested their effect on attracting the common house mosquito, Culex pipiens . Results We collected 19 microbial isolates from T. vulgare nectar, representing at least 12 different taxa which we identified with 16S or 26S rDNA sequencing as well as by biochemical and physiological tests. Three microorganisms, Lachancea thermotolerans, Micrococcus lactis , Micrococcus luteus , were grown on culture medium and tested in bioassays. L. thermotolerans grown on nectar, malt extract agar, or in synthetic nectar broth significantly attracted C. pipiens females. The odorant profile produced by L. thermotolerans varied depending on the composition of the culture medium used. Surprisingly, all three microbes grown separately, but presented concurrently, attracted fewer C. pipiens females than L. thermotolerans by itself. Conclusions Floral nectar of T. vulgare contains various microbes whose odorants contribute to the odor profile of inflorescences. In addition, one of the microbes, the yeast L. thermotolerans, produced odorants that attract Cx. pipiens females. As the odor profile of L. thermotolerans varied with the composition of the culture medium, we hypothesize that microbe odorants inform nectar-foraging mosquitoes about the availability of certain macronutrients which, in turn, affect foraging decisions by mosquitoes.

摘要
昆虫与微生物之间存在广泛的跨界信号交流。例如，花蜜中的微生物可改变其营养组成，并产生气味分子以修饰花的气味谱，进而吸引昆虫传粉者。蚊虫可取食花蜜并参与植物传粉。本研究从菊蒿（Tanacetum vulgare）的花蜜中分离得到微生物菌株，鉴定了其产生的气味物质，并测试了这些物质对尖音库蚊（Culex pipiens）的引诱效果。

结果
本研究从菊蒿花蜜中分离得到19株微生物，通过16S或26S核糖体DNA（rDNA）测序、生化及生理试验，鉴定出至少12个不同类群。选取耐热拉克酵母（Lachancea thermotolerans）、乳酸微球菌（Micrococcus lactis）和藤黄微球菌（Micrococcus luteus）3株微生物在培养基上培养后开展生物测定。在花蜜、麦芽提取物琼脂或合成花蜜培养液中培养的耐热拉克酵母，可显著引诱尖音库蚊雌蚊。耐热拉克酵母产生的气味谱会因所用培养基的组成不同而发生变化。令人意外的是，3株分别培养的微生物同时施用时，其引诱的尖音库蚊雌蚊数量显著低于单独使用耐热拉克酵母的组别。

结论
菊蒿的花蜜中含有多种微生物，其产生的气味物质可参与花序气味特征的构成。其中，耐热拉克酵母产生的气味物质可引诱尖音库蚊雌蚊。由于耐热拉克酵母的气味谱会随培养基组成发生变化，我们推测微生物产生的气味物质可向花蜜觅食的蚊虫传递特定大量营养素的可获得性信息，进而影响蚊虫的觅食决策。