沙拐枣属植物果实性状的数值分类研究

 筛选出我国沙拐枣属(calligonum L.)植物15种,测定了果实刺/翅毛排数、刺/翅毛质地、扭曲方向、扭曲程度等11项指标。应用主成分分析法对15种沙拐枣属植物果实性状的各项指标进行了分析,结果表明,第一主成分贡献率为29.704%,其中沟槽深度、肋棱突起程度、刺毛稀疏度是影响沙拐枣果实性状的主要因素;第二主成分贡献率为25.598%,主要包括了基部加宽度、果组。对沙拐枣果实性状指标进行PCA排序可将其划分为4类:第一类包括翅/刺毛排数、刺毛稀疏度、肋棱宽度;第二类包括果组、果实扭曲方向、扭曲程度;第三类包括刺毛/翅质地、刺毛/翅粗硬、沟槽深度、肋棱突起程度;第四类包括果实基部是否加宽。通过第一、第二和第三主成分分析体现了沙拐枣果实趋向于沟槽浅、肋棱浅,而果实刺毛密度趋向于增加。

Numerical Taxonomy of Fruit Characteristic of Calligonum L.

The 11 morphological and anatomic traits in fruit twist direction, spine/wing texture, and twist degree, etc. of 15 species of Calligonum L. from China were studied by use of principal component analysis (PCA). Results showed that the contribution of the first principal components accounted for 29.704%, among which sparse degree of fruit spine, trench depth, arris raised degree are the main factors influencing fruit characters; the contribution of the second principal components accounted for 25.598%, which included base width, fruit type. In PCA analysis, factors affecting fruit characters can be divided into four classes: the first class including spine/wing row number of fruit, sparse degree of fruit spine, arris width; the second consisting of fruit type, fruit twist direction, and twist degree; the third involving spine/wing texture, hard and thick degree, trench depth, arris raised degree; and the forth comprising base width. Analysis of the first, the second and the third principal components disclosed that the fruit of Calligonum L. grows to be shallow trench and narrow arris, and the fruit spine density to be intense so as to adapt to desert environment.