番荔枝科几种植物花部特征的繁殖与传粉适应意义

番荔枝科花部结构变异十分丰富，花瓣形成独特的传粉室，退化雄蕊与繁殖和传粉过程密切相关，具有雌蕊外花粉管生长，是探讨花部结构进化与传粉适应的极好材料。过去的研究由于缺少花部解剖学和器官发生的证据，还停留在观察的、静态的描述传粉现象的阶段，与繁殖和传粉过程相关的诸多特征还未被发现；对于花部特征的认识是孤立的，缺乏对特征之间相关性的研究和分析。本项目选择国内分布的番荔枝科8属8种植物，分别处于不同的系统分支，具有独特的花部特征，代表不同的传粉室类型。综合运用扫描、切片、免疫细胞化学等多种实验手段对与繁殖和传粉过程相关的花部性状进行形态学、解剖学和发育式样的系统研究，正确认识花各部形态特征的多样性、花部结构的同源性及形态变异的本质，在类群系统演化的框架下，综合分析特征之间的相关性以及花部特征与生殖系统和传粉适应之间的关系和作用，探讨花部特征的进化适应意义，为番荔枝科系统分类研究提供更多的实验证据。

The Annonaceae are a natural pantropical family of approximately 120-200 genera with over 2,000 species. It is the largest family within Magnoliids, as formalized by the Angiosperm Phylogeny Group, in which they remain one of the most important lineages in the early radiation of basal angiosperms. The family has the greatest diversity at the macromorphological level and pollination system as well. There are some specific floral traits like pollination chamber, different type of staminodes, and extra-gynoecial pollen-tube growth, which are suitable materials for investigating the floral evolution and pollination adaptation. However, most of the flower characters have not been correctly recognized, and the interdependency among them still remains unclear. The applicant and the team members have described the floral traits, pollination biology and breeding systems for eleven species from nine genera. In this project, the applicant is going to conduct extensive researches on the morphology, structure and ontogeny of floral synchrony, together with field investigations and behavior experiments in laboratory, by using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and immunocytochemistry, mainly focused on 8 species from 8 genera, representing four lineages (subfamilies), different type of pollination chamber and specific floral features, respectively. The aims of the project are: providing fundamental knowledge of floral synchrony, evaluating the relationship existing in the Annonaceae between anthetic duration and the occurrence of pistillate/staminate-phase floral synchrony, especially clarifying the floral traits on pollination adaptation and reproductive strategies, and assessing the problem on systematics and phylogeny comparing with previous studies.