雌雄同株植物性别决定的内在因子及功能分析

Jatropha curcas L. (Euphorbiaceae) is one of species having tremendous potential for the development of biomass energy,which produces rich-oil seed. The study found that the low proportion of jatropha female and male flowers seriously affect the seed production. Besides, our researches show that early development of female flowers presented bisexual tissues, followed by male tissue degradation and develop into unisexual flowers at the later developmental phases, in contrast, the male flowers always had unisexual tissues during floral development. However, male and female structure are little different in early development, and the key point of male and female differentiation is that the top cells of early germ tissues proliferate or not.And the traditional model of flower development seems not to fully explain these sex differentiation phenomena. Other researchers also reported the similar phenomenon of plant sex determination, and consider that there exist some sex determination factors and mechanisms different from the traditional flower development model in plant sex determination process. Current reports show that the sex-determining intrinsic factors and mechanisms of dioecious plants were understood more, however, few reports in the plants having male and female flowers at the same time , especially woody plants. But, the phenomenon of male and female flowers occuring in the same plant is widespread. Therefore, this project aims to explore the mechanism of sex determination in monecious and woody plants by researching the intrinsic factors of sex determination and their functions in jatropha, further to improve flower development model and to lay a good theoretical basis for the jatropha new variety breeding.

麻疯树属大戟科，麻疯树属植物，种子含油率高，是目前最具开发潜力的生物质能源树种之一。研究发现麻疯树雌雄花比例低，严重影响种子产量。麻疯树性别分化过程中,雌花发育初期具有两性组织，随后雄性组织退化而发育成单性花，雄花发育过程中仅有雄性组织；雌雄花发育早期，显微结构差异较小，雌雄分化的关键点是早期生殖组织的顶端细胞是否增殖。传统花发育模型不能完全解释这些性别决定现象，其它一些研究者也报道了植物性别决定的类似现象，认为在植物性别决定过程中存在不同于传统花发育模型的性别决定因子和性别决定机制。目前，雌雄异株植物性别决定因子及机制的研究较深入，对雌雄花同株的性别决定的内在因子及机制报道较少，特别是木本植物。而雌雄花同株现象又普遍存在。因此，本项目通过研究麻疯树性别决定的内在因子及其功能，探索雌雄同株植物和木本植物的性别决定机制，完善花发育模型；同时为培育高产麻疯树新品种奠定理论基础。