对黑龙江省49（7×7）个三系杂交粳稻组合的亲本和F1代生育期进行了研究。结果表明，F1代生育期受父本、母本共同影响，并且均为正相关，但生育期较长的亲本对F1的影响要大于生育期较短的亲本；F1代生育期均比双亲中生育期较短的亲本和双亲平均生育期长；当父母本生育期差异小于8 d时，F1代生育期可以超越生育期长的亲本，但当父母本生育期差异大于8 d时，F1代生育期介于父母本平均值和生育期较长的亲本之间，并且接近于生育期较长的亲本。

The growth period and its genetic regularity of 49（7×7） three-line hybrid japonica rice combinations and its parents in Heilongjiang province was studied. The results indicated that the growth period of F1 was common effected by both parents, and was positive correlation either. The influence of parent with longer growth period was bigger than the shorter. The growth period of F1 could be longer than the shorter one of parents and the average of them.The growth period of F1 surpassed the parent with longer growth period when the difference less than 8 day. The growth period of F1 was between the average and the longer one when the difference between them more than 8 day, and close to the parent with longer growth period.