摘要
为研究超旱生植物高枝假木贼和盐生假木贼适应荒漠环境的生殖物候特征,运用单因素方差分析和线性回归法对两个自然种群的始花期、终花期、花期持续时间、相对开花振幅、开花同步指数、果实发育进程和种子宿存量等方面分别进行统计分析,结果如下:1)高枝假木贼和盐生假木贼均在夏季7、8月的高温环境中开花;2)高枝假木贼种群花期持续时间为52天,平均花期同步指数为0.69±0.094,盐生假木贼种群花期持续时间为49天,平均花期同步指数为0.792±0.07,两个种群的开花高峰比例均低于20%;3)随着大气平均温度呈线性下降趋势时,高枝假木贼和盐生假木贼种子鲜重均呈指数增加;4)种子成熟后不易脱落,在秋季种子成熟至降雪覆盖之前有68%±2高枝假木贼种子和83%±2.14盐生假木贼种子宿存在母株上,形成气生种子库。以上结果表明:在遭受相同自然选择的压力下,两种假木贼选择高温持续开花、低温结实和气生种子库储备趋同的生殖物候特点。该研究对于诠释荒漠地区植物特殊的适应机制具有重要价值,为资源的合理利用和生态系统的保育提供依据。
Reproductive phenology is considered as an important fitness factor, it plays a crucial role in reproductive success. Our aim is to investigate the reproductive phenology of Anabasis elatior and A. salsa. To better understand these features, we observed 20 A. elatior and A. salsa individuals respectively in the wild population in 2012, including the first flowering date, duration, mean flowering amplitude and last flowering date, then calculated synchrony indices, seeds development process and aerial seed storage characteristics. Important findings are as follows. 1 ） Both plants begin blooming at the high temperature in summer. 2） Both plants flower once a year. The flowering span of the population are approximately 52d （A. elatior） and 49d （A. salsa）. The synchrony index is 0.69 ±0.094 （A. elatior）, 0. 792 ±0.07 （A. salsa）, respectively. The flowering peak ratio of two species are less than 20%. 3 ） The seeds grow slowly after flowering in summer with high temperature, and when the temperature is lower, they begin to grow exponentially and the fresh weights significantly increase. 4） Before snowfall is covering, 68% ±2 seeds from A. elatior and 83% ±2.14 seeds from A. salsa retain on the mother plants. Above results indicate that both plants choose convergent reproductive phenology of high temperature continuous flowering, Low - temperature solid and the aerial seed bank reserves in order to increase the survival chances in extreme environment and provide a guarantee for occurrence of viviparous seedlings in early spring. Reasereh about the reproductive phenology of A. elatior and A. salsa is of significance for understanding the adaptation mechanism to habitats.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2014年第6期160-164,共5页
Journal of Arid Land Resources and Environment
基金
国家自然科学基金项目(31270436)
克拉玛依市科技计划项目(SK-2012-15)资助
关键词
高枝假木贼
盐生假木贼
生殖物候
Anabasis elatior
Anabasis salsa
reproductive phenology
