试验于1988～1990年在江苏农学院水稻网室内进行。供试品种(组合)为汕优63和献改优63。在群体水培及盆栽条件下,生育前、中、后期设计不同氮素处理,调节根量、根系活力和颖花量,研究结实期根系活力对籽粒灌浆结实的影响。结果表明:(1)结实期颖花根活量越大,籽粒主要灌浆期灌浆强度越大。随着颖花根活量的增加。灌浆强度增加幅度,一次枝梗籽粒:中部>下部>上部,二次枝梗籽粒:上部>中部>下部;当颖花根活量大于0.876μgα-NA/颖花·h时,中部一次枝梗籽粒的灌浆强度将大于上部;(2)颖花根活量与全穗、穗上,中、下部一、二次枝梗籽粒的饱粒率均呈显著或极显著线性正相关。随着颖花根活量的提高,一、二次枝梗籽粒的饱粒率的增加幅度均是下部>中部>上部;(3)颖花根活量较小时,开花越早的强势花的粒重越高,随着颖花根活量的增加,强、弱势花粒重的差异变小,当颖花根活量大于0.841μgα-NA/颖花·h时。中部一次枝梗籽粒的粒重将大于上部;(4)提高颖花根活量能明显地提高结实期叶片的净同化率。延缓叶面积指数的下降速度,并能促进光合产物向籽粒运转,这是提高颖花根活量能显著提高结实率和千粒重的重要生理原因。认为水稻高产栽培在增加颖花量的同吋,必须使根量和根系活力得到同步增长,以保持较高的颖花根活量,这是提高结实率和粒重的重要途径。 The experiment was carried out in the rice net room of Jiangsu Agricultural College from 1988 to 1990. Test varieties (combination) for the Shanyou 63 and offer excellent 63. Under the conditions of hydroponics and pot culture, different nitrogen treatments were designed before, during and after fertilization to regulate the root activity, root activity and spikelet volume, and to study the effect of root vigor on the grain filling and fruiting in the grain-filling stage. The results showed that: (1) The greater the spikelet capacity of spikelets during the grain filling stage, the greater the grain filling intensity during the grain filling stage. With the increase of spikelet activity. Grain weight of the primary branch: middle> lower> upper and secondary branches: upper> middle> lower; when the root volume of spikelets was greater than 0.876μgα-NA / spikelet h, The grain filling intensity will be greater than the upper part; (2) The spikelet activity of spikelets has significant or extremely significant linear positive correlation with the grain filling rate of the spikelets of upper, middle and lower parts of spikelets. With the increase of the root activity, the increase rates of grain-filling rate of the primary and secondary branches were lower> middle> upper; (3) The higher the grain weight, the smaller the difference between the strong and the weak grain weight as the spikelet vigor increased, and when the root volume of spikelets was greater than 0.841μgα-NA / spikelet h. The grain weight of the primary stalk in the middle part will be larger than that in the upper part. (4) Increasing the root volume of the spikelet can obviously increase the net assimilation rate of the stubble leaves. Delaying the decline of leaf area index and promoting the photosynthate to the grain, which is an important physiological reason to increase the root volume of spikelets and improve seed setting rate and 1000-grain weight. It is considered that high yielding cultivation of rice should increase the root volume and root vigor synchronously with the increase of spikelet yield, in order to maintain a high spikelet root activity, which is an important way to increase the seed setting rate and grain weight.