水稻产量主要由颖花数(总粒数)与结实率所决定,高产栽培要求有较多的颖花数与较高的结实率。但单位面积上的颖花数与结实率常呈显著负相关。在稻体内碳水化合物的含量为一定时,过多地增加颖花数,必然会造成颖花间对碳水化合物的激烈竞争,结果使部分弱势颖花因灌浆物质不足而停止发育,成为空秕粒。因此,在高产稻作上存在 The yield of rice is mainly determined by the number of spikes (total grains) and seed setting rate. High yielding cultivation requires more spikes and higher seed setting rate. However, the number of spikes per unit area and the rate of seed setting often showed a significant negative correlation. When the content of carbohydrates in rice body is constant, excessive increase of the number of spikelets will inevitably lead to fierce competition between spikelets for carbohydrates. As a result, some disadvantaged spikes will cease to develop due to lack of grouting substances and become empty grains . Therefore, the existence of high-yielding rice