水稻抽穗受精后进入灌浆充实期,此时供给源主要依靠顶部三张冠层叶的光合作用,其光合同化率的大小对稻谷产量的影响甚大。它们之间还直接存在源与库的相关关系,源足则库大库满;源亏则库小库虚。水稻在中,低产水平时,谷粒的供给源大致70％左右靠抽穗后一个多月时间的光合作用;在高产情况下,谷粒的供给源则90％以上靠功能叶供给。在高产栽培技术上,人们在水稻抽穗前后采取 Rice heading into the filling period after heading and fertilization, when the supply mainly depends on the photosynthesis of the top three canopy leaves, and its photosynthetic assimilation rate has a great impact on the yield of rice. Between them there is a direct correlation between the source and the library, the source of the full library full library; At medium and low-yielding rice levels, the supply of grain is about 70% by photosynthesis for more than one month after heading; in high yield, more than 90% of the supply of grain is supplied by functional leaves. In high-yielding cultivation techniques, people take it before and after rice heading