Interspecific and intraspecific variation of ectomycorrhizal fungi associated with Eucalyptus ecosystems as revealed by ribosomal DNA PCR-RFLP
Interspecific and intraspecific variation of ectomycorrhizal fungi associated with Eucalyptus ecosystems as revealed by ribosomal DNA PCR-RFLP
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DOI：
10.1017/s095375620100418x
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发表时间：
2001-07
期刊：
影响因子：
2.5
通讯作者：
M. Glen;I. Tommerup;N. Bougher;Philip A. O'Brien
中科院分区：
文献类型：
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作者：
M. Glen;I. Tommerup;N. Bougher;Philip A. O'Brien
冈瓦纳植被，特别是澳大利亚地区，是物种丰富的外生菌根真菌在地上和地下的形式与超过100种记录在小（1公顷）补丁的森林。区分共同发生的外生菌根真菌根协会在本地（自然或荒地）植被或种植园，并区分它们从其他较大的担子菌，如木材和落叶分解真菌，地方很大的要求分子鉴定，特别是如果种间的相似性和种内变异发生在目标序列。109种较大的担子菌从一个单一的森林位置，其特征在于两个基因组区域（核rDNA ITS和线粒体LSU）的PCR-RFLP图谱。超过三分之一的物种，其中多个分离株进行了测试，在一个或两个基因组区域的种内变异。这种显着的高变化的问题，以前的假设种内ITS序列变异，并强调了价值的综合分子和形态数据库，包括凭证标本。它还强调了使用一个以上基因组区域的分子研究的价值。种间相似性普遍的Cortinariaceae，特别是在ITS区。大多数Cortinariaceae物种的歧视，实现了在mtLSU区域与ITS结合使用的变化。这一新的信息提出了可能性，ITS序列是更保守的和mtLSU更多的变量比其他23个家庭的物种。在其他家庭，种间ITS变异较大，mtLSU配置文件分组的家庭内的物种。两个基因组区域的高变异表明边缘桉树林两个相邻的不同管理区块之间的真菌种群结构可能存在差异。讨论了这种变化对生态学、生物多样性评价和生态系统管理的意义。
Gondwanan vegetation, and the Australian region in particular, is species rich for ectomycorrhizal fungi in epigeous and hypogeous forms with over 100 species recorded in small (1 ha) patches of forests. Distinguishing co-occurring ectomycorrhizal fungi as root associations in native (natural or wildlands) vegetation or plantations and discriminating them from other larger basidiomycetes, e.g. wood and leaf litter decomposer fungi, places large demands on molecular identification, especially if interspecific similarities and intraspecific variation occur in target sequences. One hundred and nine species of larger basidiomycetes from a single forest location were characterised by PCR-RFLP profiles of two genomic regions (nuclear rDNA ITS and mtLSU). Over one-third of the species for which multiple isolates were tested showed intraspecific variation in either one or both genomic regions. This remarkably high variation questions previous assumptions about intraspecific ITS sequence variation and highlights the value of integrated molecular and morphological databases including voucher specimens. It also emphasises the value of molecular investigations that use more than one genomic region. Interspecific similarities were common among the Cortinariaceae, especially in the ITS region. Discrimination of most Cortinariaceae species was achieved using variation in the mtLSU region in conjunction with the ITS. This new information raises the possibilities that the ITS sequence is more conserved and the mtLSU more variable than among species of the other 23 families. In the other families, interspecific ITS variation was greater and the mtLSU profiles grouped species within families. The high variation in the two genomic regions indicated possible differences in the fungal population structure between two adjacent, differently managed blocks of Eucalyptus marginata forest. The significance of this variation to ecology, biodiversity assessment and ecosystem management are discussed.