高山栲种子的超低温保存

Cryopreservation of Castanopsis delavayi Seeds

高山栲种子是一种典型的顽拗型种子,在常规保存手段下,其种子发芽率丧失很快。将高山栲种子脱水干燥至5.01%～25.35%5个含水量梯度,置于液氮中保存6个月,结合不同的回湿处理后测定种子发芽率、相对电导率、脯氨酸(Pro)质量分数、丙二醛(MDA)质量摩尔浓度4个指标,评价超低温条件保存高山栲种子的效果。结果表明,将种子含水量脱水至20.36%,置于液氮中保存,然后用质量分数为20%的聚乙二醇(PEG)回湿处理10 h效果最佳,在此条件下,种子发芽率明显高于对照和其他处理;适宜的含水量和回湿处理使种子在储藏过程中丙二醛质量摩尔浓度降低,脯氨酸质量分数增高。

Castanopsis delavayi seeds are typical recalcitrant seeds,and they drastically lose its viability with routine storage methods.The seeds were dried to different moisture contents from 5.01% to 25.35% to explore the effects of cryopreservation,and then stored in LN2 for six months.The seed germination rate,the electrical conductivity,the contents of proline（Pro） and malondialdehyde（MDA） were investigated with different combination treatments of humidification.The optimum condition of cryopreservation is 20.36% of seed moisture content and pre-humidification for 10 hours with 20% PEG.In this condition,the vigor of seeds is distinctly higher than others.The results of three physiological indices indicate that the malondialdehyde content is decreased and the proline content is increased because of the moderate moisture content and humidification.