康定柳对增温性别间差异响应的分子机理

In nature, as the varied inhabits and the specially geographical isolation, the ratio of males to females is not always 1:1 for a certain dioucious plant. Based on our previous studies on poplars, a woody species of male-based sex ratio, we got a conclusion that Populus males had a better adaptability than females to the environmental stresses. However, for another woody species with a female-based sex ratio, whether willow females have a better adaptability to environmental changes than males, it is still unknown. In this study, Salix paraplesia Schneid., a species that widely distributes in the Western Sichuan Plateau and plays important role in preventing soil erosion and desertification control, will be used as a model plant to investigate the sex-specific responses to increased temperature. Using plant physiological and biochemical methods combining with transcriptome, metabolome and transgene analysis in tissues, we will illuminate to (1) whether there are sexually differential responses of S. paraplesia to an increased temperature; (2) the different gene regulated networks between males and females responding to increased temperature; (3) the different tread-offs in growth and defense in carbohydrate allocation and energy metabolism during the vegetative and reproductive growth stages. We believe that these results will not only give a reasonable explanation for the bias of sex ratio with the increasing attitude, but also provide some theory evidences on plant gender selection during alpine vegetation restoration and ecological engineering construction.

针对高海拔地区高山柳性别比例偏雌性的独特生态学现象，围绕“雌雄植株对环境变化适应能力的差异决定了其性别比例”的科学假设，以广泛分布于川西高原地区的康定柳为研究对象，应用植物生理生态学、组学和分子生物学等多种技术手段，开展模拟增温条件下性别差异响应的生理和分子机制研究，为预测未来气候变暖背景下山地植被性别比例偏倚规律提供参考。同时，通过对进入生殖生长前后植株在物质分配上的对比研究，探讨“生长-防御-繁殖”的权衡关系。研究结果不仅能为自然条件下柳树性别比例偏雌性现象提供分子水平的解释，也能为山区生态工程建设和植被恢复的性别选择方面提供理论依据。

本项目以自然状况下，性别比例偏雌性的康定柳为研究对象，应用植物生理生态学、多组学和分子生物学等多种技术手段，开展模拟增温条件下性别差异响应的生理和分子机制研究。具体结果如下：开展了自然分布区康定柳性别比例调查，明确了其随海拔升高性别比例偏雌性的分布规律；开展了不同发育时期雌雄花芽性别偏倚性基因和代谢产物差异的研究，明确了开花早期阶段雄花具有较大的投资成本；开展了雌雄杨柳树对夜间增温具有性别特异性响应研究，探明了杨树雄株和康定柳雌株对夜间增温有较好的适应性；开展了雌雄康定柳根系、叶片在增温下转录组、蛋白质组和代谢组学研究，明确了性别特异性响应通路和组织特异性响应网络，揭示了雄株叶片在增温下具有较强的能量代谢，而雌株具有较好的防御能力；同时，也对比了开花前后雌雄柳树随季节变化资源分配的差异，明确了生殖在其中的重要作用。该研究不仅为自然界中性别比例偏雌性现象提供分子水平的解释，丰富木本植物对环境变化性别差异响应的研究内容，也为开花前后物质分配在植物“生长-防御-繁殖”之间的权衡关系提供了理论支撑，为山地生态工程建设和植被恢复中性别选择提供理论依据。