对1993年北方稻区水稻区试中中粳中熟组和中早粳晚熟组参试品种(系)进行了产量构成因素的比较分析,结果表明:两种熟期品种的产量构成从总体上看是相似的,但又都有各自的特点。在中粳中熟品种的选育中,应首先提高穗数,而在中早粳晚熟品种的选育中,穗粒数的作用最大。 The comparative analysis of the yield components of middle-late japonica rice cultivar Zhongzijing and middle-late japonica late maturing rice in the test area of ​​northern rice in 1993 showed that the yield components of the two ripening cultivars were generally Look is similar, but they all have their own characteristics. In the middle Japonica maturing varieties breeding, we should first increase the number of ears, and in the early maturing varieties of late japonica varieties, grain number the largest role.