有花植物两性功能展示的花柱类型具有极大的多样性，比如：同型花柱、花柱二态、异型花柱等，这种花柱多态性为研究植物异型花柱的起源和演化提供了很好的研究模式。虽然植物学家们普遍接受的“花粉转移模型”和 “避免自交模型”从不同的角度推测了异型花柱的起源与演化关系，但是大部分研究类群缺失了两个模型的中间过渡状态-花柱二态，因此，几种花柱类型之间的演化途径和演化转变并没有得到准确的结论。本项目在前期研究的基础上，拟选取花柱二态的独花报春属及其近缘属为研究对象，包括系统发育的关键类群以及演化模型涉及的同型花柱、花柱二态、二型花柱的代表类群，通过异型花柱的形态特征和繁育系统研究，确定各个研究物种的花柱类型和自交不亲和系统，并在系统树构建的基础上进行性状演化分析，推断花柱类型的祖征以及几种花柱类型的演化转变，揭示独花报春属及其近缘属异型花柱的演化途径，为被子植物繁育系统的演化提供新的证据。

The stylar model of sexual system presents great diversity in flowering plants, such as homostyly, stylar dimorphism, and heterostyly. The style polymorphism provides a research model and system for the origin and evolution of heterostyly of plants. Although both “pollen transfer model” and ”Selfing avoidance model” made precise predictions of origin and evolution of heterstyly, the evolutionary transition and pathway of monomorphism, style dimorphism and distyly were not resolved because of the absent of style dimorphism in most genus. To address these questions, we will choose Omphalogramma with style dimorphism and its closely relatives with stylar polymorphism as research samples, considering wide range of polymorphism variation and phylogenetic key taxon. Characterization of style polymorphism and incompatibility system will be determined by floral measurement and breeding system study in wild populations. Furthermore, we will mark the heterostyly types and incompatibility system on the phylogenetic tree to infer the most recent common ancestor of style polymorphism and evolutionary transition of heterostyly in Omphalogramma and relative genus. These expected experimental results permit us to reveal the origin and evolutionary pathway of style polymorphism in Omphalogramma and relative genus. This project will provide a new evidence for the evolution of breeding system in angiosperm.