中文摘要：

对475份狗牙根种源的17个植物学特征进行研究。采用多种分析方法研究其形态多样性,为优良品种选育提供理论依据及参考。结果表明,1）不同种源形态性状具有广泛的变异性。狗牙根在高度（草层高度）、营养器官长度（叶片长度和节间长度）等方面变异较大;其次为生殖器官长（花序长）;狗牙根在质地（叶宽）、节间直径及小穗数方面的变异较小;在穗枝数方面的变异幅度最小。2）不同种源形态性状间存在显著或极显著的相关性。狗牙根愈高,其叶片越宽大,匍匐枝越发达,花序愈长,穗枝数及小穗数愈多,叶毛也越多。3）欧氏距离21.50处可将475份狗牙根分为两大类群,即高大型和低矮型。

英文摘要：

The genetic diversity of C.dactylon accessions originating from different regions were assessed using morphological markers： morphological diversities of 475 accessions of Cynodon dactylon were studied using 17 morphological characters.1） Abundant morphological variation existed in accessions of C.dactylon.The variations of turf height,leaf length,and internode length were the largest,followed by inflorescence length,leaf width,internode diameter,and spikelet number.Inflorescence branch numbers had the least variation.2） There were significant correlations among some morphological characters of C.dactylon accessions.With increasing turf height,C.dactylon had longer leaves,stronger stolons,longer inflorescence lengths,more inflorescence branches and spikelets,and more hairs.3） The accessions clustered into two major morphological types using the unweighted pair-group method with arithmetic averages（UPGMA）,designated as either high type or low type.