祁连山青海云杉天然群体的种实性状表型多样性

STUDY ON PHENOTYPIC DIVERSITY OF CONE AND SEED IN NATURAL POPULATIONS OF PICEA CRASSIFOLIA IN QILIAN MOUNTAIN,CHINA

以系统揭示其表型变异程度和变异规律为目的,对祁连山青海云杉(Picea crassifolia)天然分布区的10个群体的8个种实性状进行了比较分析。采用方差分析、多重比较,相关分析、聚类分析等多种分析方法,对群体间和群体内的表型多样性进行了讨论。方差分析结果表明,各种实性状在群体间都存在极显著差异,除球果干质量和球果长/球果径外,其余性状在群体内都存在着极显著的差异;表型分化系数即群体间变异为27.18%,小于群体内的变异(72.82%);球果长、球果径、球果干质量、球果形状指数、种子长、种子宽、千粒重和种子形状指数的变异系数分别为:10.08%、5.80%、19.29%、9.66%、8.38%、15.34%、6.52%和13.94%;8个种实性状间多数呈极显著或显著的正相关,球果干质量、种子长、千粒重、球果长和球果径为青海云杉易测定和重要的种实性状;种实性状呈现出以经度变异为主的梯度规律性;通过表型性状的聚类分析可以将青海云杉10个群体划分为4类。

Aims Our objective was to determine 1 ） the phenotypic variation of cone and seed in natural populations and 2） the relationship between phenotypic variation of natural population and different distribution areas in Picea crassifolia. Methods Field investigation and analysis of the natural distribution of P. crassifolia in Qilian Mountain led to our selection of four cone characters and four seed traits in 10 trees from each of 10 populations. We examined morphological diversity among/within populations based on analysis of eight phenotypic traits. Variance analysis, multi-comparison, correlation analysis and hierarchical cluster analysis were used to analyze experimental results. Important finding Analysis of variance for all traits showed significant differences among/within populations except for cone dry weight and cone length/cone width. The mean phenotypic differentiation coefficient （Vst） among populations was 27.18%, compared to 72.82% within populations. In different individuals within populations, the CV of cone length, cone width, cone dry weight, cone length/cone width, seed length, seed width, seed length/seed width, 1 000 seeds weight was 10.08%, 5.80%, 19.29%, 9.66%, 8.38%, 15.34%, 6.52% and 13.94%, respectively. Most of the cone and seed traits were positively correlated. The cone dry weight, seed length, 1 000 seeds weight, cone length, cone width were thought to be the most important cone and seed traits that were easy to measured in P. crassifolia. The spatial variation of traits of natural populations was related most strongly to longitude. According to UPGMA cluster analysis, the 10 populations of P. crassifolia could be divided into four groups. This study indicates that there is rich phenotypic variation of cone and seed in natural populations of P. crassifolia in Qilian Mountain and thereby provides theoretical ref- erences and basic data for genetic resources conservation, utilization and improvement in P. crassifolia.