Variation in Phenolic Compounds within a Birch (Betula pendula) Population
Variation in Phenolic Compounds within a Birch (Betula pendula) Population
复制标题
桦树（Betula pendula）种群中酚类化合物的变化
DOI：
10.1023/a:1005582611863
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发表时间：
2000
影响因子：
2.3
通讯作者：
M. Rousi
中科院分区：
文献类型：
--
作者：
Marja;R. Julkunen;M. Rousi
在以往的研究中，在桦树种群之间甚至在单个无性系之间发现了相当大的防御化学的定性和定量差异。然而，关于自然种群中自然再生的成年桦树的变异信息仍然缺乏。本研究对30棵自然再生的20年白桦（Betula pendula）连续两年的叶片酚类成分进行了分析，以表征单株树的化学成分，分析其年变化，并确定种群内单株树的化学相似性。主要酚类化合物为黄酮类苷、杨梅素和槲皮素衍生物。叶片间浓度的年际变化较大。在大多数树木中，1998年的浓度明显高于1997年；对于某些化合物，检测到的增幅高达50%。然而，对于某些单独的树木，化学物质的数量在年份之间没有差异。因此，当树木的选择或分组是基于二次化学时，应仔细考虑数量变化。采用定性UPGMA方法进行分类，共发现4种化学型。这两年的分组是相似的，从质量上讲，单个树的结果似乎与采样年份无关。单株树化学特征的稳定性表明，质量受基因型的严格控制，这为化学分类提供了一种识别工具。在叶片防御化学中发现的高种群内变异可能提供对不同类型昆虫（通虫或专虫）的保护，从而对种群生存产生积极影响。
In previous studies, the qualitative and quantitative variation found in defense chemistry among birch populations and even among individual clones has been considerable. However, information about variation among adult, naturally regenerated birch trees from natural populations is still lacking. In this study, the phenolic composition of leaves of 30 naturally regenerated 20-year-old birch (Betula pendula) trees was analyzed for two successive years in order to characterize the chemical composition of individual trees, analyze the annual variation, and determine chemical similarities among individual trees within a population. The main phenolic compounds were flavonoid glycosides, myricetin, and quercetin derivatives. Annual variation in concentration among leaves was large. In most trees, concentrations were markedly higher in 1998 than in 1997; for certain compounds, the detected increase was as much as a 50%. However, for some individual trees, there were no differences between years in chemical quantity. Thus, when selection or grouping of trees is based on secondary chemistry, quantitative variation should be considered carefully. With the qualitative UPGMA method of classification, four chemotypes were found. The grouping was similar for both years, and qualitatively the results of an individual tree seem to be independent of sampling year. The stability in chemical profile of individual trees suggests that quality is tightly controlled by genotype, which provides a recognition tool for chemotaxonomy. The high within-population variation found in leaf defense chemistry may provide protection against different types of insects (generalists or specialists) and, thus, have positive effects on population survival.