选用‘Y两优689’杂交水稻种子为材料,将11.0%、13.0%和14.5%含水量的种子采用纸袋和密封袋包装于室温和5℃下贮藏12个月,测定贮藏后种子活力、生活力、酶活性、赤霉素(GA3)和脱落酸(ABA)含量及其代谢基因表达量变化。发现不同含水量种子采用不同包装于5℃贮藏12个月后种子活力、生活力显著高于室温贮藏。室温下贮藏,11.0%含水量种子活力和生活力显著高于13.0%,13.0%显著高于14.5%,但均显著低于贮藏前;13.0%和14.5%含水量种子纸袋包装贮藏的活力和生活力显著高于密封袋,而11.0%含水量密封袋包装贮藏种子的活力和生活力显著高于纸袋。5℃下,不同含水量种子采用不同包装方式贮藏后发芽率仍保持在80.0%以上,最高可达94.0%,保持较高的活力和生活力。种子贮藏后α-淀粉酶、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)和超氧化歧化酶(SOD)活性变化与种子活力变化整体一致,种子活力越低,α-淀粉酶、POD、CAT、APX和SOD活性也相对较低,能反应出种子质量高低。贮藏后种子活力越低的种子ABA含量越高,而GA3含量越低,ABA和GA3比值越高种子发芽能力越弱。进一步对GA3和ABA合成和代谢基因的研究发现,杂交水稻种子贮藏12个月后,种子活力越高,ABA合成基因Os ABAox2和分解基因Os NCED2相对表达量都较低,相应的其ABA含量也较低,而GA3合成基因Os GA20ox1相对表达量较高,分解基因表达量Os GA2ox5相对较低,相应GA3含量较高。因此高活力种子在萌发过程中有较多的GA3积累,ABA含量较少,促进了种子萌发。
The present study was designed to study the effects of storage conditions on hybrid rice seeds ‘Y Liang-you 689'. The seeds with 11.0%, 13.0% and 14.5% moisture content(MC) were packed by both paper and plastic bags, then stored at room temperature and 5℃, respectively. The changes of seed vigor, viability, enzyme activity, contents of abscisic acid(ABA), gibberellins(GA3) and their related genes expression were measured after storage 12 months. The seeds stored at 5℃ had higher seed vigor and viability than those stored at room temperature under different MCs and packing methods. When storage at room temperature, seeds with 11.0% MC significantly higher than those of 13.0% MC in seed vigor and viability, then 13.0% MC seeds significantly higher than those of 14.5% MC, however, was significantly lower than those of non-storage control. Seeds stored in paper bags recorded higher seed vigor and viability when seed moisture content keep at 13.0% and 14.5% levels than those in plastic bags. On the other hand, seeds stored in plastic bags recorded higher seed vigor and viability when seed moisture content keep at 11.0% level. The seeds kept high seed vigor and viability when storage at 5℃, the germination of the seeds with different seed moisture contents packed by different packing methods kept above 80.0%, the highest germination was about 94.0%. The activities of α-amylase, peroxidase(POD), catalase(CAT), ascorbate peroxidase(APX) and superoxide dismutase(SOD) were consistent with vigor index after storage. The lower of seed vigor, the lower of the activities of α-amylase, POD, CAT, APX and SOD. These parameters could reflect the degree of the seed quality. The higher of the seed moisture content, the lower of seed vigor, the higher of the ABA content, while the content of GA3 was in lower lever. In addition, the seeds with higher rate of ABA/GA3 had lower ability of germination. Further studies showed that the expression of Os ABAox2 related ABA synthesis and Os NCED2 relate