Sexual differences in flower defense and correlated male‐biased florivory in a plant–florivore system
Sexual differences in flower defense and correlated male‐biased florivory in a plant–florivore system
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DOI：
10.1111/j.1600-0706.2010.18585.x
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发表时间：
2010-11
期刊：
影响因子：
3.4
通讯作者：
K. Tsuji;T. Sota
中科院分区：
文献类型：
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作者：
K. Tsuji;T. Sota
雄性偏向的食花现象是植物与食花动物相互作用中的一个显著现象，并且可能与花的性状和性别表达的进化有关；然而，其适应意义尚未得到很好的理解。我们研究了尺蛾Chloroclystis excisa对一种性别多态的灌木柃木（Eurya japonica）花芽的取食情况，以揭示花的性别与蛾的产卵偏好、蛾幼虫的生长表现以及植物酚类物质组成之间的关系。在野外，Chloroclystis excisa会取食雄株和两性株上的花芽，但从不取食雌株上的花芽。在实验室中，蛾对雄性花芽表现出强烈的产卵偏好，而幼虫在雌性花芽上无法存活。死亡仅仅是因为取食了覆盖雌性花芽的花萼。雌性花萼中总酚类物质和缩合单宁的浓度高于雄性花萼。这些结果表明，在抵御食花行为方面可能已经进化出了显著的性别差异，这与花的性别分化有关，并且食花动物可能已经进化出对防御较弱的花性别的强烈偏好，作为一种反适应。
Male-biased florivory is a prominent phenomenon in the interaction between plants and florivores, and is potentially related to the evolution of flower traits and sex expression; however, its adaptive significance is not well understood. We studied florivory in the geometrid moth Chloroclystis excisa utilizing flower buds of a sexually polymorphic shrub, Eurya japonica, to reveal relationships between flower sex and moth oviposition preference, moth larval performance, and plant phenolics composition. In the field, C. excisa exploited flower buds on male and hermaphrodite trees but never those on female trees. In the laboratory, moths showed a strong oviposition preference for male over female flower buds, and larvae did not survive on female buds. Mortality was caused solely by feeding on the calyx covering the female bud. Female calyces contained higher concentrations of total phenolics and condensed tannins than did male calyces. These results suggest that substantial sexual differences in defense against florivory may have evolved in association with the differentiation of flower sexes and that a strong preference for the weakly defended flower sex may have evolved in florivores as a counter-adaptation.