摘要
种子萌发行为的受控机制是生殖生态学的重要研究内容。通过对适宜的温周期下,不同贮藏时期果翅对梭梭种子萌发影响的研究。结果表明:梭梭种子在温周期为5℃/25℃,5℃/15℃和15℃/25℃(暗/光=12 h/12h)中均能快速萌发。果翅对秋天新成熟种子的萌发有显著的抑制作用,使种子处于强迫休眠状态;果翅对种子萌发的抑制作用随着贮藏时间的推移逐渐降低,到翌年春天(4月)解除这种抑制作用。果翅对梭梭种子萌发行为的调控作用确保了种子在合适的时间萌发与种群的成功定居,这也是梭梭在荒漠地区广泛分布的主要原因。
Haloxylon ammodendron is an important plant species in desert vegetation, and the plant communities dominated by H. ammodendron are extensively distributed in desert regions in China, such as the Junggar Basin, northeast Tarim Basin, Hexi Corridor, Tengger Desert, Ulanbuh Desert and Qaidam Basin in China. In this study, the experiments were carried out to determine the effects of fruiting wings at different storage stages on the germination of H. ammodendron seeds in alternating temperature regimes. Alternating temperature regimes of 15℃/25℃, 5℃/15℃ and 5℃/25℃ and 12 h/12 h photoperiod conditions were used. The results are as follows： H. ammodendron seeds can germinate in a wide range of thermoperiod regimes of 5℃/25℃, 5℃/15℃ and 15℃/25℃. The germination capability of fresh mature seeds of H. ammodendron is very high, but the fruiting wings significantly inhibit the germination of fresh mature seeds in autumn. The inhibition of fruiting wings to the germination of H. ammodendron seeds is gradually reduced with prolonging the storage time, and completely lost in next spring （April）. The inhibition of fruiting wings can maintain the dormancy of H. ammodendron seeds until the conditions are favorable for germinating. Fruiting wings inhibit the germination of H. ammodendron seeds under lower temperature in late autumn and winter, but they are not inhibitory in spring. Fruiting wings may allow determining the season and controlling the timing of germination of H. ammodendron seeds, thus this species can survive in severe desert habitats.
出处
《干旱区研究》
CSCD
北大核心
2006年第4期558-561,共4页
Arid Zone Research
基金
国家自然科学基金项目(30260009)
教育部新世纪优秀人才支持计划(2005)
新疆教委优秀青年学者奖励计划(XJEDU200409)资助
关键词
梭梭
果翅
种子萌发
温变周期
Halaxylon ammodendron
fruiting wing
seed germination
thermoperiod operiod
