变温处理对藏北高原3种禾本科牧草种子萌发的影响

The Effect of the Changing Temperature Treatment on the Germination of Three Gramineae Grass Seeds in the Northern Tibetan Plateau

通过设置变温条件(20℃/10℃、25℃/10℃、25℃/15℃),研究变温处理对藏北高原草地早熟禾、三毛草、垂穗披碱草3种禾本科野生牧草种子萌发特征的影响。结果表明,垂穗披碱草的发芽率、发芽势随着温度的升高呈现出先增加后减少的趋势,最适萌发温度为25℃/10℃;三毛草和草地早熟禾的发芽率、发芽势、发芽指数均随着温度的升高而增加,最适萌发温度为25℃/15℃;此外,在相同的温度条件下,3种禾本科野生牧草种子的发芽率、发芽势、发芽指数也不相同,总体表现为垂穗披碱草的发芽率、发芽势、发芽指数最高,种子萌发时间最短。

By setting the variable temperature conditions,we studied the effect of the changing temperature treatment on the germination characteristics of three gramineae grass seeds in the Northern Tibetan Plateau,namely,Poa pratensis L.,Trisetum Bifidum,and Elymus Nutans Griseb.The result showed that the germination rate and germination potential of Elymus Nutans Griseb increased firstly and then decreased with the increasing temperature,and the optimum germination temperature was 25℃/10℃;the germination rate,germination potential and germination index of Trisetum Bifidum and Poa pratensis L.increased with the increasing temperature,and the optimum germination temperature was 25℃/15℃.In addition,under the same temperature,the germination rate,germination potential and germination index of the three gramineae grass seeds were also different.The general manifestation was that the germination rate,germination potential and germination index of Elymus Nutans Griseb were the highest and its germination time was the shortest.