杂交水稻制种父母本花期全遇是夺取制种高产的保证。而调节好父母本播差期又是影响花期全遇的基础。如今调差方法颇多 ,如常用的四同法、时差法、叶差法、温差法等 ,它们各有优缺点。这里推荐一种新方法———出叶速度法。１方法Ｙ＝Ｘ×（Ｒｎ-Ａｎ +３．５）式中 :Ｙ为父母本 Hybrid rice seed production of all parents of flowering is to seize the seed production of high yield guarantee. The regulation of the parents of the broadcast period is affecting the full flowering of the foundation. Today, there are many methods of transfer, such as the four common method, time difference method, leaf difference method, temperature difference method and so on, which have their own advantages and disadvantages. Here is a new method recommended --- out of speed method. 1 Method Y = X × (Rn-An +3.5) Where: Y is the parent