小麦强弱势粒胚乳异步发育差异的机制及其调控途径研究

小麦不同穗位的小穗和不同粒位上的颖果发育差异显著，存在强弱势粒异步发育的现象。弱势粒发育差和粒重低，既制约产量的提高，又影响品质的改良，是小麦生产上长期要解决而至今未攻克的难题。前期工作中发现，小麦强弱势粒胚乳结构、淀粉理化性质以及基因表达存在差异，然而，造成这种差异的机制及调控途径还不清楚。.本项目拟以大穗型小麦品种为材料，精确标记颖果发育的时间，运用电镜观察、15N同位素标记、X光摄影与成像、基因过表达和RNA干扰等技术，着重研究：（1）小麦强弱势粒在胚乳细胞分裂、分化与充实的差异；（2）小麦强弱势粒胚乳细胞淀粉体和蛋白体发育对粒重和品质形成的影响；（3）淀粉和蛋白质合成关键基因在调控小麦强弱势粒异步发育中的作用；（4）小麦弱势粒转化为强势粒的有效调控途径。.研究结果不仅能深化小麦颖果发育的机制，丰富细胞生物学、作物生理学等学科知识，而且对挖掘小麦增产潜力，改善小麦品质具有重要意义。

The spikelet at different panicle position and the caryopsis at different grain position grow and develop differently, that is to say, the superior and inferior grains develop asynchronously. Poor development and lower grain weight for inferior grains are a serious problem in the agricultural production, which is not conquered until now. It not only restricts the improvement of wheat yield, but also affects the quality improvement. In our previous work, we found that there were differences in endosperm structure, starch physicochemical properties and gene expression between wheat superior and inferior grains..In this project many technologies including electron microscopy, 14C and 15N isotope labeling, X-ray photography and imaging, gene overexpression and RNA interference will be used. By marking precisely development time of caryopsis, the wheat cultivars with large-panicle will be chosen to conduct researches as follows: (1) The differences in division, differentiation and filling of endosperm cell between wheat superior and inferior grains;(2) The effect of development of endosperm amyloid and protein body on grain weight and quality formation;(3) The role of key genes in starch and protein synthesis in the regulation of asynchronous development of between wheat superior and inferior grains. (4) Effective ways to control the transformation of inferior grains into superior grains..The results can not only deepen the mechanism of wheat caryopsis development and enrich the knowledge of cell biology and crop physiology, but also play an important role in exploring the potential of wheat yield and improving wheat quality.