模拟干旱胁迫下45份早熟禾种质资源种子萌发特性比较

Comparison of Seeds Germination Characteristics of 45 Bluegrass Germplasm Resources under Simulated Drought Stress

干旱胁迫是限制早熟禾种子萌发的主要环境因素。以青藏高原地区的45份早熟禾(Poa L.)种质资源为试验材料,设置4个聚乙二醇(PEG-6000)浓度模拟干旱胁迫,测定发芽率和发芽势等6个指标,运用隶属函数法和系统聚类法对供试材料进行抗旱性评价。结果表明:随着干旱胁迫的增强,各试验材料6个指标均呈下降趋势,其中相对发芽势和相对活力指数受干旱胁迫影响较大,可以作为早熟禾种质资源抗旱性鉴定的关键指标;聚类分析将材料分为3大类:09-066草地早熟禾等10份材料为抗旱材料,09-237冷地早熟禾等20份材料为中等抗旱材料,09-016冷地早熟禾等15份材料为干旱敏感材料。

Drought stress is one of the leading environmental factors limiting seeds germination of bluegrass(Poa L.).The present study measured six main indexes of 45 bluegrass germplasm resources from the Qinghai-Tibet Plateau under simulated drought stress,by setting four different concentrations of polyethylene glycol(PEG-6000).The evaluation of drought resistance of these materials was performed by the membership function method and system clustering.The results showed that six indexes of all resources exhibited a decreasing trend with increased drought stress,in which the relative germination potential and the relative vigor index were the two most affected indexes,considered bluegrass drought resistant vital indicators.Cluster analysis results divided the materials into three categories:10 materials as drought-resistant(09-066),20 as moderate drought-resistant(09-237),and 15 as drought-sensitive(09-016).