冠层调控对贵州喀斯特山区水稻冠层光分布及产量形成的影响机制

冠层内部光照不足或光分布不均是导致水稻减产或产量不稳定的主要原因，合理的冠层结构和冠层光分布是提高光能利用率和水稻产量的重要途径。本研究拟以不同株型水稻品种为材料，通过设置生态环境、密度与氮肥互作和花后遮光试验调控水稻群体冠层结构而改变冠层光分布，分析贵州喀斯特山区不同水稻群体的冠层结构和冠层光分布差异，重点就水稻冠层结构、冠层光分布与产量形成的关系进行探讨。本项目旨在探明贵州喀斯特山区水稻群体的冠层结构、冠层光分布和产量形成的特点，在理论上阐明水稻冠层结构对冠层光分布、光合氮素利用、辐射利用和产量形成的影响机制，构建水稻冠层结构和冠层光分布与光合氮素利用、辐射利用和产量形成模拟模型。从而明确喀斯特山区水稻理想冠层结构指标，揭示喀斯特山区水稻高产稳产的形成机制，为云贵高原、四川等寡照地区的水稻高产稳产栽培和株型改良育种提供理论基础和技术支撑。

Lack of or uneven distribution of light within rice canopy is a major determinant of low and unstable yield. Reasonable canopy structure and canopy light distribution within rice canopy are the important way for improving light use efficiency and rice yield. In this project, by conducting eco-environmental experiment and field experiments of interaction between density and nitrogen, and shading treatment after flowering to regulate rice population canopy structure and obtain different light distribution within the canopy，rice varieties with different plant type will be used to investigate the canopy structure and light distribution variation of different rice population in karst mountain area of Guizhou province, especially the relationships among rice canopy structure，canopy light distribution and yield formation. The objectives of this project are to ascertain canopy structure, canopy light distribution and yield formation characteristic of different rice population in Guizhou karst mountain area, to elucidate the influence mechanism of rice canopy structure on canopy light distribution, photosynthetic nitrogen utilization, radiation utilization and yield formation, and to establish the simulation models among canopy structure, canopy light distribution, photosynthetic nitrogen utilization, radiation utilization and yield formation. It would be helpful to ascertain ideal canopy structure indicators of rice and discover the mechanism of rice yield formation and yield stability in Guizhou karst mountain area, and the results could provide theoretical basis and technical support for rice high and stable yielding cultivation and plant type breeding in sunless areas including Yunnan-Guizhou Plateau and part region of Sichuan Province.