不同含水量野生稻种子库存24年后活力研究

【目的】探讨种子在种质库长期贮藏的最适含水量,评价种子长期保存后的活力,为种子长期安全保存提供科学依据。【方法】用35℃加温干燥,将初始含水量为14.80%的普通野生稻种子干燥至6种梯度的含水量10.56%、9.50%、8.70%、7.50%、6.60%和6.35%后,密封包装贮藏于种质库中进行长期保存试验,24年后测定其种子发芽力和田间生长能力,并进行方差分析。【结果】含水量为14.80%、10.56%、9.50%、8.70%、7.50%的种子发芽势、发芽率、发芽指数分别与贮藏前相比差异极显著,下降明显不宜长期保存;含水量为6.35%的种子发芽势、发芽率、发芽指数和成苗率与贮藏前相比差异不明显,发芽率仍保持在98.33%,成苗率为92.33%,活力水平最高。【结论】35℃加温干燥是种子入库前干燥的安全温度,野生稻种子在低温干燥种质库长期保存最适含水量为6.35%。

Effect of long term storage of 24 years of wild rice seeds under different seed moisture regimes on germination and growth vigour

[Objective]The present study was carried to explore the effects of long-term seed storage in gene bank under optimal moisture conditions, after a comprehensive evaluation of long-term preservation of seeds vigor, also to gene bank safety storage provide the scientific basis of wild rice seed and other crop seeds, achieve the purpose of long-term security preservation of inventory seed. [Method]The wild rice seeds with 14.8% initial moisture content were dried at 35℃ up to final moisture contents of 10.56, 9.50, 8.7, 7.50, 6.60 and 6.35%. These seeds having different moisture content were packaged, sealed and stored in gene bank for long-term storage. After 24 years, the seed germination percentage, germination energy, seed germination index and their growth performance under field conditions were determined. [Result]Results showed that germination percentage and germination index decreased significantly in seeds stored with moisture contents of 14.8, 9.5 and 8.7% compared to the seeds before storage, so these moisture contents were not found suitable for long-term storage of seeds. The seeds stored with 6.35% moisture content showed 97, 98.33 and 48.55% germination energy, germination percentage and germination index, respectively. Further, in field performance test, the percentage of seedlings was recorded as 90.67, which was almost equal to those recorded before the storage of seeds. [Conclusion]The seeds drying at 35 ℃ up to 6.35% moisture content were found best and this technique may be used for long term preservation of wild rice seeds in gene bank.