米老排天然群体的种实表型变异研究初报

Phenotypic Diversity of Seeds and Fruits in Natural Populations of Mytilaria laosensis

以系统揭示表型变异程度和变异规律为目的,对米老排（Mytilaria laosensis Lecomte）天然分布区8个群体的6个种实性状进行了比较分析.采用巢式方差分析、多重比较、相关分析、聚类分析等多种分析方法,对米老排群体间和群体内的表型变异及其与地理气候因子的相关性进行了探讨.结果表明：米老排6个种实性状在群体间和群体内变异丰富,各个性状在群体间和群体内差异均达到极显著水平;6个性状的表型分化系数均值为33.73％,群体表型性状分化以群体内变异为主;米老排各性状的平均变异系数为13.90％,变异幅度为9.73％～18.39％;种子的大小系数与种子的千粒重呈极显著正相关；除种子形态指数外,总体上,种子性状变异呈现出以经度为主的梯度规律性；群体间表型性状的Mahalanobis距离与地理距离间显著相关（r=0.459 4,p=0.02）；根据Mahalanobis距离进行UPGMA聚类,可以将8个群体大致分为4类.研究结果为进一步收集保存、评价筛选以及创新利用米老排的种质资源提供了科学依据.

In order to reveal the phenotypic variation patterns of the seed and fruit traits of natural M.laosensis populations in different distribution areas,an investigation was conducted on 6 seed and fruit traits of 8 natural M.laosensis populations.We examined the morphological diversity among and within populations based on analysis of 6 phenotypic traits.Nested variance analysis,multi-comparison,correlation analysis and hierarchical cluster analysis were used to analyze the experimental results.There were significant differences in 6 seed and fruit traits among and within the populations.The mean phenotypic differentiation coefficient for the six traits was 33.73％ which suggesting that the variance within the populations was the main part of the phenotypic variation.The average coefficient of variance（CV） among 6 traits was 13.90％,and the range of variation was 9.73％ to18.39％.The size coefficient of seed was positively correlated with thousand seed weight.In general,the spatial variation of seed traits of natural populations was strongly related to longitude.There was significant relationship between geographic distances and mahalanobis distances calculated from all phenotypic traits（r=-0.459 4,p=0.02）.According to UPGMA cluster analysis by mahalanobis distances,the 8 populations of M.laosensis could be divided into 4 groups.These findings will provide scientific basis for collecting,evaluating and utilizing the germplasm resources of M.laosensis.