Molecular α-taxonomy of Japanese ferns using rbcL sequence data as the first key information

一般来说，蕨类植物的形态比被子植物简单得多。由于蕨类植物通常缺乏用于物种识别的良好形态特征，因此在一个形态种中可能包含多个隐种。近年来，利用PCR和直接测序技术从野生植物中收集DNA核苷酸序列数据变得更加容易。这类分子信息主要用于系统发育分析，但也可用于α-分类学（识别自然存在的物种）。当形态学不能提供足够的物种划分信息时，DNA序列的特征可以为α-分类提供替代的有用信息。我们正在尝试建立一种适用于任何形态简单植物的分子α-分类新方法。在本研究中，我们研究了远亲蕨类类群如Asplenium nidus（Aspleniaceae）、Stegnogramma pozoi…More （Thelypteridaceae）、Osmunda cinnamomea、O. claytoniana、O. regalis （Osmundaceae）和Cheiropleuria bicuspis （Cheiropleuria bicuspis）中rbcL序列的形态内特异性变异。在每个物种中，我们都发现了大量的rbcL序列变异。采用人工杂交实验和同工酶分析方法，对印度尼西亚Mt Halimun国家公园发现的A. nidus不同rbcL类型之间可能存在的遗传分离进行了仔细的研究。并对各rbcL类型进行了生态观察。我们的研究结果表明，这些rbcL类型的A nidus是隐种，因为它们是生殖隔离的，遗传和生态分化良好。哈利门山国立公园内的5种rbcL虽然仅凭叶子的大体形态很难区分，但也应该作为单独的物种来对待。蕨类植物中rbcL序列的大量变化可能表明它们也由几种不同的生殖隔离的隐种组成，就像A.nidus一样。我们还计划在这些物种中应用与野针鼹相同的策略，以确定它们的物种状态。少

Generally, ferns have much simpler morphology than angiosperms. Since ferns usually lack the good morphological characters available for specied recognition, multiple cryptic species may be contained within one morphological species. Recently, it has becom easier to collect DNA nucleotide sequence data from wild plants using PCR and direct sequencing techniques. This kind of molecular information has mostly been used for phylogenetic analysis, but can also useful for α-taxonomy(recognition of naturally existing species). The characters of DNA sequences may provide alternative useful information for α-taxonomy when morphology does not provide enough information about species delimitation. We are now trying to establish new molecular α-taxonomical method which is applicable to any morphologically simple plants. In this research project, we examined intra-morphospecific variations of rbcL sequences in distantly related fern groups such as Asplenium nidus(Aspleniaceae), Stegnogramma pozoi … More (Thelypteridaceae), Osmunda cinnamomea, O. claytoniana, O. regalis (Osmundaceae) and Cheiropleuria bicuspis (Cheiropleuriaceae). In each species, we found a large amount of rbcL sequence variation. In A. nidus, we carefully examined possible genetic isolation between different rbcL types found in Mt. Halimun National Park, Indonesia using artificial crossing experiments and allozyme analyses. We also conducted ecological observation of each rbcL types. Our results suggest that these rbcL types of A nidus are cryptic species because they are reproductively isolated, genetically and ecologically well differentiated. The five rbcL types in Mt. Halimun National Park should be treated as separate species even though they are difficult to ve distinguish only by their leaf gross morphology. The large amount of rbcL sequence variation in fern species may suggest that they also consist of several different reproductivelu isolated cryptic species, just as A.nidus does. We are also planning to apply the same strategy used for A. nidus for these species in order to determine their species status. Less