不同海拔梯度糙皮桦和紫果云杉种子的萌发变异  

Variations of Betula utilis and Picea purpurea seed germination at different altitudes.

作　　者：王桔红[1,2] 张勇[1] 崔现亮[2] 杜国祯[2] 

机构地区：[1]河西学院生态研究所,甘肃张掖734000 [2]兰州大学干旱农业生态教育部重点实验室,兰州730000

出　　处：《生态学杂志》2009年第4期589-594,共6页Chinese Journal of Ecology

基　　金：国家自然科学基金资助项目(30470307)

摘　　要：对青藏高原东缘不同海拔梯度糙皮桦(Betula utilis)和紫果云杉(Picea purpurea)种子经低温贮藏后的萌发进行研究。结果表明:1)糙皮桦和紫果云杉种子的萌发率和萌发速率随母体植株海拔的升高而增大;2)来自不同海拔的种群,种子的萌发率和萌发速率随低温贮藏时间的延长而增大,尤其是高海拔生境的糙皮桦种子经过较长时期的低温贮藏后(80或160d,3℃～4℃),萌发率达到最大(94%和90%)。说明海拔是造成种群间种子萌发能力差异的主要原因之一;不同时期的低温干燥贮藏也不同程度地影响种子的萌发行为,使生长在不同海拔梯度的种群能够通过调节种子的萌发时机降低幼苗建植的死亡风险,保障了物种延续。Betula utilis and Picea purpurea seeds were collected from different altitudes on the eastern Qinghai-Tibet plateau, and their germination behavior under an alternative temperature regime （20 ℃/5 ℃ ; light/dark, 12/12 h） following cold storage （3 ℃-4 ℃ ; 0, 40, 80 and 160 days） was studied. The results showed that the germination rate of B. utilis and P. purpurea seeds increased with increasing altitude of their mother plants, and the seeds from different altitudinal populations tended to increase their germination rate with increasing duration of cold storage. In particular, the seeds of B. utilis from high altitude （3000 m） had a maximum germination percentage （94% and 90% , respectively） after cold storage for 80 and 160 days. The findings indicated that both the altitude of mother plants and the duration of cold and dry storage had significant effects on the seed germination behavior of the two species. The adaptive germination strategy, i. e. , regulating the timing of seed germination, of the population individuals at different altitudes could maximize the probability of their seedling survival, and ensure their race proliferation.

关 键 词：种子萌发 种群 海拔 低温贮藏 

分 类 号：Q948[生物学—植物学]