Data from: Influence of asymmetrical mating patterns and male reproductive success on the maintenance of sexual polymorphism in Acer pictum subsp. mono (Aceraceae)

Populations of Acer species often contain more than three sexual phenotypes with very complex sexual polymorphism such as duodichogamy, protandry, and protogyny. We investigated whether mating patterns and male reproductive success are important factors that maintain sexual polymorphism in Acer. Paternity analyses were used to estimate rates of outcrossing and disassortative mating, as well as male reproductive success, in Acer pictum subsp. mono. A pollen-transfer model was modified to investigate whether the unequal ratios of sexual phenotypes were associated with observed mating patterns. The mating pattern of Acer pictum subsp. mono was mainly outcrossing and disassortative among the sexual phenotypes. Although the duodichogamous phenotype showed a significant amount of intraphenotypic mating, the frequency did not exceed that of disassortative mating. No significant differences in male reproductive success were observed among sexual phenotypes. The pollen-transfer model demonstrated that sexual phenotype ratios could be maintained by the observed mating pattern in the population. The results indicated that disassortative mating among the sexual phenotypes can maintain sexual polymorphism in A. pictum subsp. mono, and ratios biased towards duodichogamy can result from frequent intraphenotypic mating in this phenotype.槭属（Acer）植物的种群通常包含三种以上的性表型，且具有极为复杂的性多态现象，例如两期雌雄异熟（duodichogamy）、雄先型雌雄异熟（protandry）与雌先型雌雄异熟（protogyny）。本研究旨在探究交配模式与雄性繁殖成功率是否为维持槭属植物性多态的关键因素。我们以元宝槭（Acer pictum subsp. mono）为研究对象，通过父本分析估算其异交率、异型交配率以及雄性繁殖成功率，并改良花粉转移模型，以探究性表型的不均衡比例是否与观测到的交配模式相关联。元宝槭的交配模式以异交为主，且在不同性表型间以异型交配为主；尽管两期雌雄异熟型性表型存在较高比例的表型内交配，但其发生频率并未超过异型交配的频率。不同性表型间的雄性繁殖成功率并无显著差异。花粉转移模型结果显示，种群中观测到的交配模式足以维持其性表型比例。本研究结果表明，性表型间的异型交配可维持元宝槭的性多态现象，而偏向两期雌雄异熟型的性表型比例，可由该表型内部高频发生的表型内交配所导致。