浚单系列玉米品种对弱光胁迫的响应

从拔节期到吐丝期进行50%遮荫处理,研究玉米品种浚单18、浚单20和浚单22对弱光胁迫的响应。结果表明,遮光处理使3个品种的植株矮化变细,叶片净光合速率、比叶重、地上干物质积累及吐丝期和成熟期叶面积指数均显著减少,中上部叶片功能期缩短1～3d,雌雄间隔期延长1～2 d;遮光处理还造成果穗缩短变细,穗粒数和子粒产量显著减少;遮光显著提高子粒中蛋白质的相对含量,赖氨酸相对含量也有所增加,而淀粉和油分相对含量则减少,但与对照相比,差异均不显著。综合性状表明,浚单20的耐荫性优于浚单22和浚单18。

Response of Xundan Maize Hybrids to Low-light Stress

An experiment for reaction of maize hybrids XD18, XD20 and XD22 to low-light stress was conducted on the farm of Henan agricultural university under 50% shading condition from jointing stage to silking stage. The results showed that, for the three maize hybrids in the treatment of shading, agronomic characters such as plant height, stem diameter, ear length, ear diameter, kernels per ear and grain yield all decreased significantly, the LAI also decreased significantly at silking and maturity stage, and the functional period of mid-upper leaves shortened by 1 - 3 days, and interval from anthesis to silking prolonged by 1 - 2 days. Meanwhile, physiological characters such as net photosynthetic rate, specific leaf weight and dry matter accumulation all decreased significantly as well. The relative content of starch and oil in grain decreased in shading treatment, while that of protein and lysine increased, especially, increased significantly in protein. The comprehensive characters suggested that shade-tolerance of XD20 would be better than that of XD22 and XD18.