水稻种子在通常条件下只能保持2～3年的生命期。杂交水稻种子的遗传性不很稳定,比常规稻种更易受环境条件的影响,导致生活力的丧失。就当前种子贮藏条件而言,杂交水稻种贮存一年,尚能保持较高的发芽力,如连续贮存两年,其生活力就远不及新鲜种子旺盛。种子在贮藏期间即使不发生伤热、霉变、虫害等事故,在经过第二个高温季节后,其发芽率也会明显下降,甚至降到20～30%,完全丧失了种用价值。因此,在生产上必须年年繁种,有时还需到海南繁种,很难做到供求一致。 Under normal conditions, rice seeds can only survive for two to three years. Heredity of hybrid rice seeds is not very stable, more susceptible to environmental conditions than conventional rice species, leading to the loss of viability. For the current seed storage conditions, hybrid rice varieties stored for one year, still able to maintain a high germination power, such as two consecutive years of storage, its vitality is far less than fresh and strong seeds. During the storage period, seeds will not germinate, mildew, insect pests and other accidents. After the second high temperature season, the germination rate will drop significantly, even to 20-30%, completely losing the seed value. Therefore, in the production must be breeding every year, and sometimes need to breed in Hainan, it is difficult to achieve the same supply and demand.