选择 4种典型的水稻株型 (上挺下挺、上挺下披、上披下挺和上披下披 )进行群体光合量的数值模拟。在模拟过程中 ,提出了一种可利用日照百分率资料推算直射光与散射光的方法 ,进而计算 1日中每小时直射光与散射光的消光系数、水平受光量、叶面受光量和群体光合量。对各小时的群体光合量求和 ,即可得到日光合量。在群体封行之前 ,依据太阳高度角的变化 ,将白昼分为 5个照光时段 ,然后分别计算逐时与逐日的光合量。模拟结果表明 :群体光合量在水稻生长前期以披散型最高 ,中期以挺立型最高 ,后期则以上挺下披型最高 ;株型效应在纬度较高的地区比纬度较低的地区明显 ,籼稻比粳稻明显。从理论上发展了中国著名水稻劳模陈永康的经验 ,为水稻育种与栽培研究提供了科学根据。 Four typical rice plant types (top-down, top-down, top-down and top-down) were selected for numerical simulation of photosynthetic rate. In the process of simulation, a method of estimating the direct light and the scattered light using the data of sunshine percentage was proposed, and then the extinction coefficient of direct light and scattered light per hour, the amount of horizontal light received, the amount of light received by foliage and photosynthesis the amount. Sum of photosynthesis of the group for each hour, you can get the amount of solar radiation. Before the group seal, according to the change of the solar elevation angle, the daylight is divided into five illumination periods, and then the photosynthesis amount is calculated respectively on a time-by-day and a day-by-day basis. The simulation results showed that the photosynthetic rate of the population was the highest in the early stage of rice growth, the highest in the late stage and the highest in the late stage, while the plant type was the highest in the areas with higher latitudes than in the lower latitudes. The indica rice ratio Japonica obvious. This paper theoretically developed the experience of Chen Yongkang, a famous model worker of rice in China, and provided a scientific basis for the research on rice breeding and cultivation.