栒子属（Cotoneaster Medikus）3种植物的比较形态与统计分析

用数量统计的方法对栒子属（Cotoneaster Medikus）植物水栒子（C. multiflorus Bge.）、毛叶水栒子（C. submultiflorus Popov.）和黑果栒子（C. melanocarpus Lodd.）的23个形态指标进行了研究。平均值和变异系数表明不同性状在不同种内的变异程度有所不同，黑果栒子的种内变异幅度较小；方差分析结果显示18个性状的种间差异显著，黑果栒子与其它两者的差异更明显；逐步判别分析筛选出了6个种间划分的关键性状（叶下被毛、花梗被毛、叶基部在中脉处的形状、叶顶端在中脉处的形状、上1/4叶缘的弧向、叶柄长/叶长），并把82份材料明确分为3组；毛叶水栒子的大部分形态性状具有水栒子和黑果栒子的居间性，但其种级地位合理。

Comparative Morphology and Statistical Analysis of 3 Species in Cotoneaster Medikus(Rosaceae)

Twenty-three morphological characters among three species, Cotoneaster multiflorus, C.submultiflorus and C.melanocarpus from genus Cotoneaster Medikus, were compared by statistical analysis. Mean value and coefficient of variability (CV) indicated that the variations at intraspecies level were more or less vary in different characters and species. Results from the one-factor analysis of variance (one-factor ANOVA) showed that there was a significant variation at interspecies level in the 18 characters studied and the variation between C. melanocarpus and the other two species was more marked. The process of Stepwise Discriminant Analysis (SDA) indicated that 6 of the characters (hair on adaxial leaf surface, hair on pedicels, shape of base in midvein, shape of apex in midvein, orientation of arc in up quarter margin, petiole length/leaf length) were the key ones to distinguish 3 species, and besides, 82 materials could be specifically categorized into 3 groups. It is reasonable to consider C.submultiflorus, which is intermediate from C. multiflorus and C. melanocarpus in morpohological characters, as a species.