东乡野生稻种子萌发不同步适应性策略的分子遗传机理研究

研究物种适应性策略的遗传机制可为濒危物种保护及野生资源利用提供理论和技术支撑。我国二级保护植物东乡野生稻是世界上分布最北的野生稻，在进化过程中，其获得了种子在早春低温条件下不同步萌发的高纬度环境适应策略。项目组在前期工作中，发现了一个控制东乡野生稻低温萌发不同步的主效QTL-qLTG5。本项目拟在此基础上，结合分子生态学和群体遗传学方法对该野生稻这种环境适应策略的遗传机制进行研究：1）构建qLTG5近等基因系，对该位点进行精细定位和基因克隆；2）阐明候选基因的生化功能及其对种子低温萌发的影响；3）解析qLTG5基因参与水稻适应性进化的群体遗传机制。预期成果不仅可以克隆控制水稻低温萌发不同步的关键基因，从基因水平阐明种子萌发不同步的环境适应性策略的分子机制，还可为该野生稻资源的保护和利用提供基因靶点，提高该野生资源保护和利用的效率。

Dongxiang wild rice（Oryza rufipogon Griff.）, which has been listed as a secondary protected plant in China, is the northernmost common wild rice in the world. It evolved into asynchronous germination in response to low temperature in early spring, a bet-hedging strategy adaptive to the high latitude environment. In our previously study, we identified a major QTL- qLTG5 conferring to asynchronous germination under the low temperature in Dongxiang wild rice. This project proposed herein is to characterize the genetic basis of the environmental adaption strategy of the bet-hedging by using integrative methods of evolutionary ecology and population genetics. The aims of this study are: 1) to fine map and clone the QTL gene; 2) to pinpoint the molecular mechanism of the target gene underlying the asynchronous germination in response to chilling; 3) to clarify the population genetic mechanism of qLTG5 gene involved in adaption to high latitude environment. The success of this project will improve our knowledge on the molecular mechanism of the asynchronous germination, the bet-hedging strategy for adaptation to its high latitude habitat. A MAS tool will be developed to facilitate the protection of endangered species and utilization of wild plant germplasm.