Abstract: Nineteen rice varieties with five types were grown at different sowing dates in 13 places of China in 1988, the results showed that the head rice rate of various varieties has different equation of effects of mean daily temperature in grain-filling period, by which variation of head rice rate of 19 varieties can be divided into two types i.e. linear type and parabola type, and the sensitivity to temperature and optimum temperature of head rice rate of 19 varieties can be decided. According to sensitivity of head rice rate, 14 varieties with parabola type variation of head rice rate can be classified into three types: sensitive, middle and dull type In optimum temperature, japonica varieties are lower than indica ones, and in the varieties of indica, late varieties are lower than medium varieties, medium varieties are lower than early varieties.

Key words: Head rice rate, Sensitivity, Optimum temperature, Type

摘要： 1988年利用5种类型的19个品种在全国不同地区13个试点进行了分期播种试验，结果表明，不同品种的整精米率具有不同的结实期日均温效应方程。据此将19个品种分为直线型和抛物线型，求得各品种整精米率对温度的灵敏度及最适温度，并接整精米率的灵敏度将14个抛物线型品种划分为灵敏型、中间型和迟钝犁。在最适温度方面，粳稻低于籼稻；籼稻中，迟熟品种低于低于中熟品种，中熟品种低于早熟品种。

关键词: 精米率, 温度, 水稻, 稻米品质