水稻是喜温的短日性作物,在短日高温条件下出穗早,长日低温条件下出穗迟。日长和温度对水稻品种的出穗迟早,起着决定性和互相促进的作用。但是具备了适宜的短日高温条件,仍需经过一定的生育日数才能出穗,这个过程长短因品种而异,是决定品种出穗迟早的重要因子。因此弄清品种对短日高温反应特性,才能了解其出穗迟早的变化规律。品种在适宜的短日高温条件下至出穗所需的最少日数,称为短日高温生育性(日人称之为基本营养生长性,但两者是有差别的)。在短日高温 Rice is a thermophilic short-day crop, which leaves early in the short day at high temperature and late at long day at low temperature. The growth of rice and temperature on rice varieties sooner or later, played a decisive and mutually reinforcing role. However, with the appropriate short-day high temperature conditions, still need to go through a certain number of birth days to spike, the length of the process varies by species, is to determine the earliest varieties of important factors. Therefore, to understand the varieties of short-day high temperature response characteristics, in order to understand the changes of the ear sooner or later. The minimum number of days required to breed a plant under the appropriate short day and high temperature conditions is called short-day high temperature fertility (what the Japanese call basic vegetative growth, but there is a difference between them). In the short high temperature