超低温保存下藓类植物孢子萌发率的变化:以6种藓类植物为例

Variation in germination rates of moss spores using a cryopreservation technique: A case study of spores from six moss species

为了检验苔藓植物孢子超低温保存方法的适用性,该文对采自不同生境中的6种藓类孢子超低温保存前的干燥时间和低温预处理进行探索,并在最适处理条件下对其中5种藓类孢子进行不同时间梯度(1 d、15d、30 d、90 d和180 d)的超低温保存研究.结果表明:①经过干燥和低温预处理后,6种藓类孢子的最高萌发率均维持在较高水平(87.25%~96.21%);②与低温预处理相比,干燥处理在孢子超低温保存中更为关键.孢子在只进行干燥处理情况下其最高平均萌发率为74.97%~96.21%,而只对其进行低温预处理时的最高平均萌发率变化较大,从21.73%到90.94%;③5种藓类孢子在液氮保存1d后的平均萌发率均最高(87.25%~96.21%),且随着保存时间的延长,所有藓类孢子的萌发率都有所下降,但仍维持在相对较高的水平(73.69%~86.60%);④葫芦藓、丝瓜藓和长蒴藓孢子在保存30d后萌发率分别为86.49%、86.60%和84.98%,卵蒴真藓和丛生真藓孢子在保存180d后萌发率仍可达到73.69%和84.17%.研究表明,藓类孢子非常适合于超低温保存,而且可能代表一种简单、稳定、高效的苔藓植物种质资源保存材料.

To evaluate the applicability of cryopreservation for bryophyte spores,this study explored the effect of dehydration time and low temperature pretreatment;the study was used to identify the optimal conditions for six moss spores collected from different habitats.In addition,varying time periods(1 d,15 d,30 d,90 d,180 d)of spore cryopreservation were studied under the optimal pretreatment conditions identified.The results showed that:①After dehydration and low temperature pretreatment,the highest germination rates of spores from the six moss species were maintained(87.25%~96.21%).②Compared to low temperature pretreatment,dehydration seems to be the key point of success for spore cryopreservation.The average spore germination rates ranged from 74.97%to 96.21%when treated with dehydration alone;in comparison,germination rates ranged from 21.73%to 90.94%when pretreated with low temperature alone.③The average germination rates of spores from five moss species maintained their respective highest level(87.25%~96.21%)after cryopreservation for 1 d and then decreased with the prolongation of storage time;nevertheless,the germination rates still remained at relatively high levels(73.69%~86.60%).④The average germination rates of spores from Funaria hygrometrica,Pohlia elongate,and Trematodon longicollis after storage for 30 d were 86.49%,86.60%,and 84.98%,respectively.The germination rates of spores from Bryum blindii and B.caespiticium reached 73.69%and 84.17%,respectively,after storage for 180 d.The study indicates that the procedure for spore cryopreservation could be a simple,stable,and efficient method for storage of bryophyte species in conservation programs.