水稻种子含水量及其对贮藏寿命的影响

The Effect of Moisture Content on Storage Life of Rice Seeds

以粳稻幸实(OryzasativaL.subsp.japonicacv.Xingshi),籼稻桂早2号(OryzasativaL.subsp.indicacv.Guizao2)水稻种子为试材,研究不同含水量水稻种子在-20℃和室温(25℃)条件下贮藏5年后的活力变化及其生理生化基础。结果表明,适度超干处理能延长种子的贮藏寿命,种子活力保持与种子含水量和贮藏温度密切相关。籼稻桂早2号种子耐干性较强,在含水量降至2.4%时,种子活力与5.8%相比无显著差异,而粳稻幸实种子活力极显著下降。不同含水量水稻种子抗氧化酶活性、可溶性蛋白和热稳定蛋白含量与种子活力呈正相关,ABA含量、磷脂酶活性随含水量降低而升高,说明种子耐干性的获得是多种生理机能共同作用的结果。幸实种子可溶性蛋白含量大大高于桂早2号,这可能是幸实种子较不耐干的关键因素。

Japonica rice (Xingshi) and indica rice (Guizao 2) seeds were used to investigate the vigor and some physiological indexes after stored at -20℃ and ambient temperature(25℃)for five years. The results showed that moderate drying could prolong the storage life of rice seeds. The indica rice (Guizao 2) seeds had strong ultra-dring tolerance. When moisture content fell to 2.4%, the vigor index of Guizao 2 seeds, compared with that of 5.8%, had no obvious change. On the contrary, the vigor index of Xingshi seeds decreased rapidly. The study also indicated that there were positive correlations between the antioxidation system, soluble proteins, heat shock proteins and vigor index. The content of abscisic acid (ABA) and phospholipase activity increased continuously during dehydration. The content of soluble proteins of Xingshi was more than that of Guizao 2, which might be a key reason for that Xingshi seeds are not tolerant to ultra-drying.