云南岩陀及其近缘种质资源群体表型多样性

Phenotypic diversity in populations of germplasm resources of Rodgersia sambucifolia and related species

为有效保护和持续利用药用植物云南岩陀及其近缘种质资源提供基础数据,采用巢式方差分析和聚类分析等方法对岩陀及其近缘种质资源共4个种(包括变种)的15个居群150个单株16种表型性状进行表型多样性分析。结果表明:不同种间表型性状变异均超过20%,变异由大到小依次为光腹鬼灯檠、岩陀、羽叶鬼灯檠、七叶鬼灯檠;居群间表型性状变异较高,其地上部分干重、单株根状茎数变异较大,变异系数均超过50%;小叶表面毛被状态变异系数为100%、小叶背沿脉柔毛色变异系数为0,因此这些性状为种和变种分类的重要依据;4个种的居群内变异系数均大于居群间,变异主要来源于居群内。种的表型多样性指数相对较高,其中根粗最高,叶表面毛被状态和叶背面沿脉柔毛色最低,总体平均多样性指数为1.39;不同种间表型多样性指数变化在1.23—1.44,岩陀最高,七叶鬼灯檠最低;通过聚类分析可将15个居群分为4类。结果暗示:岩陀及其近缘种质资源的遗传改良应适当地减少抽样居群数,增加居群内的家系数,重视居群内优良单株的选择;种质资源的保护应尽量保护一个居群的完整性。

The objective of the present study was to examine phenotypic diversity in populations of Rodgersia sambucifolia and related species, thereby providing important information to assist in the effective protection and sustainable utilization of these germplasm resources. Nested ANOVA and cluster analysis were used to elucidate phenotypic diversity, based on 16 traits, in 150 plants from 15 populations of R. sambucifolia and three related species （ including varieties） in Yunnan Province, China. The average within-species coefficient of variation was greater than 20%. Rodgersia sambucifolia var. estrigosa possessed the largest coefficient of variation, followed successively by R. sambucifolia, R. aesculifolia, and R. pinnata. There was great variation in phenotypic traits within populations. The largest within-population variation coefficients （〉 50% ） were those for dry weight of aerial plant parts, the number of rhizomes per plant, and hair on the adaxial leaflet surface （ 100% ）, while that for color of flocculence on the abaxial leaflet surface was 0. These traits could thus be used to distinguish R. sambucifolia and its related were higher within than between populations, with most species. For the four species, phenotypic variation coefficients observed variation derived from within-population variability. Species phenotypic diversity indexes were relatively high, with those for rhizome diameter the highest, and those for adaxial leaflet surface hair and color of flocculence on the abaxial leaflet surface the lowest. The overall mean phenotypic diversity index was 1.39, ranging from a high of 1.44 in R. sambucifolia to 1.23 in R. pinnata. In addition, cluster analysis showed that the 15 populations of R. sambucifolia and related species could be divided into four categories. The results obtained here suggest that ： 1 ） sampling more individuals within a single population, rather than collecting a few individuals from many different populations, is the best strategy for genetic improvement of R. sambucifolia germplasm resources; 2） more attention should be focused on choosing superior individuals during the process of genetic improvement; and 3 ） population integrity is the key determining factor for protection of germplasm resources of R. sambucifolia and related species.