油菜冠层光高效品种的筛选及其光高效机理研究

Improving light use efficiency for rapeseed canopy will contribute to make use of abundant solar energy resources in autumn and winter，and improvement for rapeseed planting techniques offers great potential in the Yangtze River Valley. It is very important to study the mechanism of high-light use efficiency for rapeseed crop canopy to stable rapeseed production and to develop fallow fields completely in winter. In this study, more than 60 varieties from all over the world will be tested for canopy light use efficiency and identified the varieties with higher light-use-efficiency for rapeseed. Experiments would been done to select different light-use-efficiency materials in different ecological regions，and to determine photosynthetic efficiency of different types of materials with different morphological parameters. Measurements of canopy structure parameter would be carried out，and explore the biochemical response pathway with higher light efficiency. The application of high-throughput sequencing methods would find the difference of gene expression, screening for high-efficiency-related EST of rapeseed. It is the application of bioinformatics and computer modeling analysis of these morphological, physiological and gene expression data to construct the physiological mechanisms of rapeseed. Findings have important theoretical and practical meaning for this scientific research, not only conducive to the development of rapeseed with high light use efficiency and the utilization of superior breeding and genetic resources, but also to improving the agronomic measures to promote more efficient utilization of solar light for rapeseed populations and aiming to large-scale production of rapeseed with light use effectively.

研究油菜冠层高光效机理为改良油菜群体的光能利用效率提供理论指导，筛选适合本种植区域的冠层光高效品种可以充分利用油菜生育期内丰富的光能资源，该研究对提高单位面积油菜产量以及破解长江流域油菜种植区冬闲田开发难题十分重要。本研究拟采用来自国内外的60个油菜品种进行多点多年冠层光能利用效率的大田筛选试验，并结合盆栽对冠层光合效率相关的群体和个体指标的研究;确定不同光效类型品种的群体冠层结构特征参数，研究与光合效率相关的生理指标。并对油菜高光效的分子机理进行初步探讨，采用高通量测序方法进行基因表达差异研究，筛选出与油菜高光效相关的EST。该研究将应用生物信息学方法分析形态、生理及基因表达数据，揭示油菜冠层光能高效利用的生理机制。项目研究结果将有利于优异基因资源的开发与利用，对油菜冠层高光效育种提供方法参考，对油菜大面积生产中光能的高效利用会有重要的理论指导与实践意义。

贵州是我国长江上游的重要油菜产区，但油菜群体冠层光能利用率不高和单位面积产量较低是影响该区域种植户积极开发冬闲田发展冬油菜种植的重要障碍。通过60多个品种的多年多点的大田盆栽试验，系统研究油菜生长阶段群体冠层的光能利用和品种资源光能利用特性差异，通过农艺措施构建不同的油菜冠层类型，从群体的角度解析油菜光能利用的群体高光效机理。主要研究结果如下：①提出并系统开展了油菜品系的高光效系数研究，通过高光效品种特性评价鉴定及光能利用效率不同类型的筛选。根据全生育期高光效系数，从长江上游种植的几十个油菜品种中筛选出了高光效品种6个和低光效品种12个。②适宜的农艺措施是构建光高效油菜群体冠层有效途径，高光效群体冠层可以播种期协调营养器官生长与生殖生长，适时迟播可提高光能利用率；增密种植有利于在60cm以上形成高光效角果层，提高冠层内光合产物的转运效率；分施控氮、适量施磷、增施钾肥、重视硼肥等养分管理可提高油菜群体光能利用；油菜高光效群体是主要是花后期冠层叶面积和角果皮面积有效调控。③油菜高光效群体冠层在苗期有利于根冠层生长地上微环境，在花后期有利于高效的角果光合作用；高光效冠层能增加油菜角果粒壳比和每角籽粒数。④ 油菜光高效群体冠层内主茎籽粒含油量最高，分枝籽粒含油量最低；油菜群体冠层变化对分枝籽粒的品质影响幅度更大。该项目系统研究了影响油菜冠层群体冠层生育期内光能利用的生理生态机制，该研究结论可直接物化为高效技术措施和可利用的品种资源，油菜高光效系数等参数和冠层群体指标的研究方法，对改良该地区油菜群体光能利用的配套生产技术和优异种质资源选育发掘利用、提高冬油菜产量、稳定种植具面积有重要意义。