水稻具有耐水性,这是它在系统发育中形成的对水分反应的遗传特性。 水稻生育过程中存在着对缺水非常敏感,且需水量较大或最大的时期。这个时期称为水分“临界期”(或需水“临界期”)。 通常认为,水稻只有一个水分临界期,即在花粉母细胞减数分裂期。但该期何以对水分有敏感反应,在理论上未见有阐明的报导。本文对从下述观点提出的水稻三个水分“临界期”,作一理论性探讨。 Rice has water resistance, which is the genetic characteristic of its response to moisture formed during phylogeny. During rice growth, there is a period that is very sensitive to water shortage and requires a large or maximum water requirement. This period is called the “critical period” of water (or the “critical period” of water demand). It is generally accepted that rice has only one critical water period, ie during meiosis of pollen mother cells. However, why this period is sensitive to moisture, there is no clear theory in the report. This paper makes a theoretical discussion on the “critical period” of rice water content from the following points.