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林业科学 ›› 2015, Vol. 51 ›› Issue (12): 35-44.doi: 10.11707/j.1001-7488.20151205

• 论文与研究报告 • 上一篇    下一篇

野生高山杜鹃群落林内自然挥发的化感成分

李朝婵1, 乙引2, 全文选1, 田红红2   

  1. 1. 贵州师范大学贵州省山地环境保护重点实验室, 贵阳 550001;
    2. 贵州师范大学贵州省植物生理与发育调控重点实验室, 贵阳 550001
  • 收稿日期:2015-06-30 修回日期:2015-10-13 出版日期:2015-12-25 发布日期:2015-12-29
  • 通讯作者: 全文选
  • 基金资助:
    国家自然科学基金项目(31460136);教育部长江学者和创新团队发展计划(IRT1227);贵州省科学技术基金项目(黔科合J字[2013]2230号);贵州师范大学博士科研基金。

The Natural Volatile Components of Allelochemicals in the Wild Alpine Rhododendron Community

Li Chaochan1, Yi Yin2, Quan Wenxuan1, Tian Honghong2   

  1. 1. Guizhou Provincial Key Laboratory of Mountainous Environmental Protection, Guizhou Normal University Guiyang 550001;
    2. Guizhou Provincial Key Laboratory of Plant Physiology and Developmental Regulation, Guizhou Normal University Guiyang 550001
  • Received:2015-06-30 Revised:2015-10-13 Online:2015-12-25 Published:2015-12-29

摘要: [目的]森林群落中化感物质挥发途径对其天然更新存在重要影响。马缨杜鹃、迷人杜鹃和露珠杜鹃是贵州百里杜鹃国家森林公园内的先锋种与建群种,收集3个高山杜鹃纯林群落林内空气来探讨化感物质成分,为百里杜鹃林区林下天然更新提供科学依据。[方法]采用典型样方法对自然状态下马缨杜鹃、迷人杜鹃和露珠杜鹃三大主要杜鹃群落做野外调查,计算各样地的Berger-Parker优势度指数、Simpson多样性指数、Pielou均匀度指数,对生物多样性特征进行分析。采用采样气袋法对3个群落林内气体挥发物进行收集,运用固相微萃取气相色谱质谱联用技术分析3个高山杜鹃群落林内气体的化感成分。[结果] 3个群落的优势度从高到低为迷人杜鹃、露珠杜鹃、马缨杜鹃,多样性指数从高到低为露珠杜鹃、迷人杜鹃、马缨杜鹃,均匀度指数从高到低为露珠杜鹃、马缨杜鹃、迷人杜鹃。SPME-GC/MS结果显示露珠杜鹃、迷人杜鹃和马缨杜鹃林内气体中分别检出17、13和11种挥发性化感物质成分,其中烷烃类物质是其主要挥发性化感成分; 3个杜鹃群落中还有萜烯类、有机酸、酯类、酮类、酚类,这些物质均属于化感物质或具有抑制作用。露珠杜鹃林内气体成分主要包括烷烃类、萜烯类、酮类和酚类等,其中相对含量最高的成分是2,2,4,6,6-五甲基庚烷(30.81%),较高的成分是5-乙基-2,2,3-三甲基庚烷(19.87%)、癸烷(11.71%)、十二烷(10.00%)。迷人杜鹃林内气体成分主要包括烷烃类、萜烯类、酯类和有机酸类,其中相对含量最高的成分是2,5-二甲基-2,5-过氧化二氢己烷(20.23%),较高的成分是5-乙基-2,2,3-三甲基正庚烷(18.13%)、十二烷(14.30%)、2,2,7,7-四甲基辛烷(10.20%)。马缨杜鹃林内气体成分主要包括烷烃类、酚类、酯类和有机酸,其中相对含量最高的成分是癸烷(22.92%),较高的成分是2,2,4,6,6-五甲基庚烷(18.11%)、γ-丁内酯(16.82%)、棕榈酸(11.65%)。[结论] 3个高山杜鹃群落具有较高的优势度和均匀度,但是多样性指数较低。高山杜鹃群落层次结构简单,在郁闭度达到90%以上的条件下,高山杜鹃的种子天然更新过程很难完成。3个高山杜鹃群落林内气体含有丰富的化感物质,以烷烃类及其衍生物为主,化感物质的种类与群落生物多样性存在正相关性。高山杜鹃群落植物产生的化感物质如何协同生境条件发挥作用还需作进一步的研究。

关键词: 高山杜鹃群落, 生物多样性, 化感作用, 气体成分, 气相色谱质谱联用

Abstract: [Objective] In forest community, the volatile pathway of allelochemical has a significant impact on its natural regeneration. Rhododendron delavayi, R. agastum and R. irroratum are the pioneer and dominant species in Baili Azalea National Forest Park in Guizhou province. Air samples are collected from pure forests of the three Rhododendron communities to analyze their allelochemical components, in order to provide a scientific basis for the natural regeneration of Baili Azalea National Forest Park.[Method] Field investigations of three major Rhododendron communities (R. delavayi, R. agastum and R. irroratum) under natural conditions were conducted using the method of typical sampling plots, Berger-Parker dominance index, Simpson's diversity index, and Pielou evenness index were calculated for each of the sample plots. Based on these parameters, biodiversity of the communities were characterized. Samples of volatile compounds were collected from the three communities using air bags. Components of the allelochemicals in the three communities were investigated and analyzed by using the solid phase microextraction (SPME) technique and the gas chromatography mass spectrometry (GC/MS).[Result] The Berger-Parker dominance index of the three communities from high to low was R. agastum, R. irroratum and R. delavayi, the Simpson index from high to low was R. irroratum, R. agastum and R. delavayi, and the Pielou index from high to low was R. delavayi, R. irroratum and R. agastum. There were respectively 17, 13 and 11 volatile allelopathy components in the air samples of R. irroratum, R. agastum and R. delavayi identified by SPME-GC/MS, and the main volatile allelopathy component was alkanes in all the three communities. Terpenes, organic acids, esters, ketones and phenols were also detected and they are allelochemicals or have inhibitory effects. The components of R. irroratum community were mainly alkanes, terpenes, ketones and phenols, and the highest component was 2,2,4,6,6-pentamethylheptane (30.81%), followed by 5-ethyl-2,2,3-trimethylheptane (19.87%), decane (11.71%), and dodecane (10.00%). The components of R. agastum community were aminly alkanes, terpenes, esters and organic acids, and the highest component was 2,5-dimethylhexane-2,5-dihydroperoxide (20.23%), followed by 5-ethyl-2,2,3-trimethylheptane (18.13%), dodecane (14.30%), and 2,2,7,7-tetramethyloctane (10.20%). The components of R. delavayi were mainly alkanes, phenols, esters and organic acids, and the highest component was decane (22.92%), followed by 2,2,4,6,6-pentamethylheptane (18.11%), γ-butyrolactone (16.82%), and palmitic acid (11.65%).[Conclusion] The three Rhododendron communities had higher dominance and evenness but lower diversity. The hierarchical structure of Rhododendron community was simple. When the canopy density exceeded more than 90%, the process of natural regeneration from seeds of alpine Rhododendron was difficult to complete. Air samples of the three Rhododendron communities were rich in allelochemicals, mainly including hydrocarbons and their derivatives. And the kinds of allelochemicals were positively correlated with community biodiversity. Further studies are required with focus on how the allelochemicals produce impacts in relation with the habitat conditions in the alpine Rhododendron communities.

Key words: alpine Rhododendron community, biodiversity, allelopathy, gas components, GC/MS

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