旱生灌木岷谷木蓝种子的休眠与萌发特征  

Seed dormancy and germination of xeric shrub Indigofera lenticellata

作　　者：曾璠 冷俐[1] 包维楷[1] 周志琼[1] 

机构地区：[1]中国科学院成都生物研究所生态恢复与生物多样性保育四川省重点实验室,成都610041 [2]中国科学技术大学,合肥230026

出　　处：《生态学杂志》2009年第12期2452-2459,共8页Chinese Journal of Ecology

基　　金：中国科学院知识创新工程项目(KZCX2-XB2-02);西部之光博士资助项目(08C2041100)

摘　　要：岷谷木蓝（Indigofera lenticellata）是横断山区干旱河谷广泛分布的豆科灌木。本文对其种子的休眠与萌发特征进行了研究。结果表明：岷谷木蓝种子具有物理休眠,其萌发困难的原因在于种皮的不透水性;种子的硬实比率高（85%）,针刺种皮和沙摩处理能有效打破种子休眠,提高发芽率,其中沙摩7h最为快速有效。岷谷木蓝种子发芽温度范围较广,10℃~30℃均可发芽,最适温度范围为20℃~30℃,低温不利于种子萌发。岷谷木蓝具有一定的抗旱性,在聚乙二醇6000（PEG）溶液模拟水分胁迫条件下,种子在25%PEG胁迫下仍能达到100%的发芽率,但水分胁迫对种子发芽有一定的延缓作用,发芽率和发芽速度降低,发芽周期和发芽准备期增长,发芽高峰期滞后。其中对于发芽能力检测的各项指标对水分胁迫的敏感性顺序为发芽指数＆gt;发芽势＆gt;发芽率。岷谷木蓝种子的发芽特征是对干旱河谷生存环境长期适应的结果。野外播种的适宜时间为4月初,并在播种前对种子进行7h的沙摩处理。Indigofera lenticellata is a leguminous shrub widely distributed in the dry valley of Hengduan Mountains.Its characteristics in seed dormancy and germination were studied in this paper.I.lenticellata seeds had the characteristics of physical dormancy,and the water-impermeability of seed coat was the main cause of difficulty to germinate.Hard seeds occupied about 85% of the total.Perforating the seed coat by a needle and scarifying the seeds by sand were the effective measures to break I.lenticellata seed dormancy.Scarification by sand for 7 h was the best treatment measure to improve the germination.The seeds germinated in a wide temperature range from 10℃ to 30 ℃,with the optimum temperature between 20 ℃ and 30 ℃.Low temperature was not beneficial to the germination.I.lenticellata had definite drought-resistant capability.Under the 25% polyethylene glycol 6000（PEG）-simulated drought stress,the seed germination rate could reach to 100%.However,drought stress decreased the germination rate,retarded the germination process,prolonged the germination cycle and preparing period,and lagged the germination peak phase.The parameters reflecting the sensitivity of I.lenticellata seed germination to drought stress were in order of germination exponent germination potential germination rate.It was suggested that the optimal time for sowing I.lenticellata seeds in the field was early April,and the seeds should be scarified by sand for 7 h before sowing.

关 键 词：岷谷木蓝 种子 温度 水分胁迫 发芽 

分 类 号：Q948[生物学—植物学]