光合作用是水稻产量形成的生理基础。水稻不同生育阶段,光合效率不同,光合效率高低与其绿叶面积群体生长率密切相关。我们曾用汕优6号等3个组合连续4年进行试验表明,在抽穗前30天至抽穗后20天共50天时间内,水稻叶面积指数增长到最大值。亩产600公斤的群体,此时段叶面积指数在6.5～8.5左右,干物质增长速度也达最大值,平均每天每平方米增重16～17克,有的超过25克,光能利用率大幅度提高,在1.67～1.88％范围,而分蘖初期仅 Photosynthesis is the physiological basis for the formation of rice yield. Rice has different photosynthetic efficiency at different growth stages, and the photosynthetic efficiency is closely related to the growth rate of its green leaf area. We have used three combinations of Shanyou 6 for 4 consecutive years of experiments showed that in the 30 days before heading to 20 days after heading a total of 50 days, the rice leaf area index increased to maximum. A group of 600 kg per mu, leaf area index at this time around 6.5 to 8.5, the maximum dry matter growth rate, the average daily weight gain of 16 to 17 grams per square meter, and some more than 25 grams of light energy utilization rate Amplitude increased in the range of 1.67 ~ 1.88%, while the early tillering only