青藏高原东部高寒草甸十字花科植物种子的休眠  

Seed dormancy characteristics of cruciferous species in the alpine meadow on the eastern Qinghai-Tibetan Plateau

作　　者：任青吉 许静[2] 刘伟[3] 

机构地区：[1]甘南州草原工作站,甘肃合作747000 [2]兰州商学院农林经济管理学院,兰州730020 [3]兰州大学干旱与草地农业生态教育部重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2009年第4期60-65,共6页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金项目(90202009)

摘　　要：实验以青藏高原东部高寒草甸19种十字花科植物种子作为材料,研究温度、生境、海拔对种子休眠的影响.结果表明:双果荠属休眠率最高,为97.3%;芝麻菜属休眠率最低且萌发开始时间和达到50%萌发率所需时间最短,均为2.6d.各温度下种子休眠率差异不明显,10℃下所有种子的平均休眠率略高,为64.9%;25℃下平均休眠率略低,为49.0%.温度对种子萌发时间影响极显著,相对高温下种子萌发开始时间和达到50%萌发率所需时间较短;海拔显著影响种子的休眠率,平均休眠率随海拔升高而增加,采自相对高海拔下的种子平均休眠率为低海拔下种子的7.1倍,但各海拔梯度下的萌发时间差异不显著;生境对种子平均休眠率的影响显著,采自滩地的物种休眠率相对较高、萌发开始时间和达到50%萌发率所需时间较长.The effects of temperature, altitude and habitat on seed dormancy of 19 cruciferous plants on the eastern edge of the Qinghai-Tibet Plateau were studied. Results show that the highest proportion dormancy （97.3%） occurred in Megadenia, days to first germination and days to 50% germination of Eruca were the shortest（2.6d）. There existed no significant difference in the mean proportion dormancy among temperature treatments. The highest proportion dormancy was at 10℃ （64.9%） and the mean proportion dormancy at 25℃（49.0%） was sIightly lower. The effect of temperature on the mean days of germination was extremely remarkable, days to first germination and days to 50% germination were shorter at relatively high temperature. The altitude had a marked effect on total proportion dormancy and the proportion dormancy increased as the altitude rose. The proportion dormancy of seeds from higher altitude displayed 7.1 times as seeds from lower altitude. There was a significant relationship between habitat and seed proportion dormancy. Generally speaking, seeds collected from the bottomland showed high proportion dormancy and long days to germination and days to 50% germination.

关 键 词：种子休眠 十字花科 高寒草甸 

分 类 号：Q945.35[生物学—植物学]