生物多样性 ›› 2021, Vol. 29 ›› Issue (8): 1073-1086.  DOI: 10.17520/biods.2021001

• 研究报告: 植物多样性 • 上一篇    下一篇

群体表型性状研究揭示环境与遗传因素对霍山石斛表型及物种分类的影响

焦振彬1,2, 罗毅波1,*()   

  1. 1.中国科学院植物研究所系统与进化植物学国家重点实验室, 北京 100093
    2.中国科学院大学, 北京 100049
  • 收稿日期:2021-01-02 接受日期:2021-03-22 出版日期:2021-08-20 发布日期:2021-05-28
  • 通讯作者: 罗毅波
  • 作者简介:* E-mail: luoyb@ibcas.ac.cn
  • 基金资助:
    美丽中国生态文明建设科技工程专项(XDA23080101);安徽省霍山县长冲中药材开发有限公司资助

Effects of environmental and genetic factors on phenotypic traits and species classification of Dendrobium huoshanense

Zhenbin Jiao1,2, Yibo Luo1,*()   

  1. 1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093
    2 University of Chinese Academy of Sciences, Beijing 100049
  • Received:2021-01-02 Accepted:2021-03-22 Online:2021-08-20 Published:2021-05-28
  • Contact: Yibo Luo

摘要:

石斛属(Dendrobium)种类繁多, 属内物种具有丰富的表型多样性。霍山石斛(D. huoshanense)为我国特有物种, 其与河南石斛(D. henanense)和细茎石斛(D. moniliforme)以及铁皮石斛(D. catenatum)等近缘种表型相似, 在分类处理中存在争议。这种争议很大程度上与植物普遍存在的表型可塑性和代际共存有关。为探究环境和代际间遗传因素对霍山石斛表型性状的影响以及霍山石斛与近缘种的物种边界问题, 本研究观测了安徽省霍山县霍山石斛(野生、林间和温室F1代、林间和温室F2代)、野生河南石斛、细茎石斛和铁皮石斛, 共计16个群体2,279株植株的假鳞茎茎长等12个表型性状; 在种内层面, 首次借鉴生态学同质园实验和遗传学代际间性状比较的方法, 对霍山石斛群体表型性状进行差异显著性检验和95%置信区间比较以及主成分和变异系数等统计学分析。在种间层面, 对霍山石斛与河南石斛和铁皮石斛等近缘种群体表型性状进行比较和分析。结果表明, 环境因素对霍山石斛假鳞茎茎长和假鳞茎直径等具有显著的影响, 代际间遗传因素对霍山石斛假鳞茎直径具有显著的影响。霍山石斛与铁皮石斛和细茎石斛等近缘种群体在假鳞茎茎长、假鳞茎直径、花瓣长和花瓣宽等表型性状方面均存在显著性差异和间隔, 但与河南石斛仅在假鳞茎表型性状方面有显著性差异。我们的研究明确了环境和代际间遗传因素对霍山石斛表型性状的影响程度, 为霍山石斛与近缘种等争议物种的分类和鉴定提供了表型证据。

关键词: 石斛, 兰科植物, 表型性状, 环境因素, 遗传因素

Abstract

Aims: Dendrobium is one of the largest genera in Orchidaceae. The species of this genus are characterized by high morphological diversity. Dendrobium huoshanense is an endemic species of China with high pharmaceutical and conservation value. However, the boundary of the species is still in debate. In this study, we aim to explore the variations of phenotypic traits affected by environmental and genetic factors, and define the boundaries among D. huoshanense and its related species.

Methods: We measured 12 phenotypic traits from 2,279 specimens in 16 populations from the dendrobiums planting base in Huoshan County, Anhui Province, East China, including wild and F1, F2 generation of D. huoshanense, wild D. henanense, D. moniliforme and D. catenatum. The F1 and F2 generations of D. huoshanense were cultivated from the seeds of random hand-pollination flowers in wild population and F1 generation population from this base, respectively. We first used common-garden experiment method and intergenerational comparison to estimate the phenotypic variations of D. huoshanense affected by environmental and genetic factors. Furthermore, the phenotypic variations of D. huoshanense and its related species were estimated by statistical analysis.

Results: The results showed that F1 and F2 generations of D. huoshanense in greenhouse and woodland conditions had larger and longer pseudobulbs than that of wild specimens under the common-garden experiment method. With the intergenerational comparison, we found that the pseudobulb diameters of F1 generation were wider than that of F2 generation. Among related species, we found that the pseudobulb lengths and diameters as well as the petals of D. huoshanense were significantly different from that of D. catenatum and D. moniliforme. At the same time, D. huoshanense only showed significant differences in morphological traits of pseudobulbs with that of D. henanense.

Conclusion: Our results suggest that both environmental and genetic factors have significant effects on phenotypic changes of D. huoshanense and affect the delineation of species boundaries among D. huoshanense and its related species.

Key words: Dendrobium, Orchidaceae, phenotypic traits, environmental factors, genetic factors