高产玉米的干物质积累与分配规律研究

在西昌特定生态条件下,高产玉米(亩产800公斤)的植株干物质消长动态呈S型曲线。出苗到拔节平均日增重0.18克,积累了总干重的2.2％,拔节到灌浆干重积累速度最快,平均日增重达5.09克,灌浆期时已积累了植株总干重的87.43％。后期干重增长趋缓,但仍以0.8克/日的速度积累了总干重的12.2％。叶片在抽雄时干重量大(45.50克),茎秆、叶鞘和苞叶穗轴则在灌浆期干重达极大值(分别是69.25克、27.00克和89.50克),以后干物质向籽粒转移,其转运量大小顺序为苞叶穗轴>茎秆>叶鞘>叶片,而籽粒的干重一直上升。各营养器官的干物质转运量的总和占籽粒干物质重量的32.79％,表明籽粒干重的67.21％是直接来自叶片的光合产物。本研究还讨论了玉米干物质积累进程的分期及特点和各生育期的干物质分配中心。

STUDY ON THE RULES OF THE DRY—MATTER ACCUMULATION AND DISTRIBUTION IN THE HIGHER YIELD CORN PLANT

The pattern of the process of the dry—matter accumulation in the whole perild of growth of the higher yield corn, with grain weight 800 kg permu, appeared in the form of a S—shaped curve. The maximum peak of dry—matter accumulation was to be about the filling stage. The highiest weight of the leaves dry—matter was at the heading stage, and the peaks of the dry—matter accumulation of other vegetative organs appeared at the filling stage. Only 32.79% amounts of the total seed weight was translated from the vegetative organs and the 67.21% seed dry—matter were from the leaves assimilation directely. This paper also discussed the differante characters of the dry—matter accumulation among the all stages and of the dry—matter distribution to seed from the vegetative organs.