目的对云贵高原滇龙胆不同居群进行形态特征变异研究,为滇龙胆遗传多样性保护和良种选育提供依据。方法采用野外调查取样,对27个滇龙胆居群根、茎、叶的15个形态性状指标进行测量和统计分析。结果滇龙胆不同居群、不同产地和同一居群内不同个体间,在不同植物学性状上均有一定变异,其中,叶片数、植株生物量、株高、分枝数等形态指标变异较大。相关分析表明,滇龙胆植株根条数、根粗和根干质量同植株地上分枝数、叶片数及茎叶干质量呈显著或极显著正相关关系。聚类分析表明,27个滇龙胆居群可分为4组,其中第III组主要分布在黔西和川中南,比较适合作为高产优良品种选育的材料。主成分分析显示,茎叶干质量、根干质量、根条数、分枝数、株高、叶长这6个形态指标是造成表型差异的主要因素。结论滇龙胆具有丰富的表型遗传多样性,并以根部表型性状变异幅度最大。在筛选高产滇龙胆种质资源时可考虑分枝数、叶片数和茎叶干质量这几个外观形态指标。

Objective To study the morphological differences among the different populations of Gentiana rigescens in Yunnan-Guizhou Plateau and provide the basis for the genetic diversity and breeding of G. rigescens. Methods Using field survey sampling, 15 morphological traits of the roots, stems, and leaves in G. rigescens from 27 populations were observed, measured, and analyzed. Results There was a certain morphological variation among the different populations, different habitats within the same origin, and different individuals in the same population, of which leaf number, plant biomass, plant height, branch number, and other morphological indicators showed a large variation. Correlation analysis showed that there was a significant or highly significant positive correlation between the root number of plants, root diameter, and dry weight of crude plant root and the number of branches, leaf number, and leaf dry weight in the aerial part. Cluster analysis showed that 27 populations of G. rigescens could be divided into four groups. Group III mainly distributed in the Western part of Guizhou and central south of Sichuan, which was more suitable for high-yield varieties as breeding material. Principle component analysis showed that leaf dry weight, root dry weight, root number, branch number, plant height, and leaf length were the major factors which could cause the phenotypic difference. Conclusion G. rigescens has the rich genetic diversity and the phenotypic variation extent of the roots is the greatest. The branch number, leaf number, and leaf dry weight of G. rigescens should be taken into consideration in screening high-yield G. rigescens germplasm.

国家科技基础性工作专项重点项目(SB2007FY020);国家科技支撑计划项目(2011BAI13B02-4);云南省科技攻关项目(2010GG026)