Apomixis, hybridization, and taxonomic complexity in eastern North American Amelanchier (Rosaceae)
Apomixis, hybridization, and taxonomic complexity in eastern North American Amelanchier (Rosaceae)
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DOI：
10.1007/bf02815379
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发表时间：
1996-01-01
期刊：
影响因子：
--
通讯作者：
Wright, WA
中科院分区：
文献类型：
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作者：
Campbell, CS;Wright, WA
无融合生殖和杂交共同导致了无眉鱼分类的复杂性。杂交结合了遗传上不同的基因组，并产生了新的形式，无融合生殖永存。无融合生殖是无孢子生殖、兼性生殖和假配子生殖，无融合生殖体通常是多倍体，花粉可育，由通才授粉。基因流动确实发生了，这在经验上是显而易见的。由于无融合生殖在遗传上比有性生殖占优势，因此涉及至少一个无融合生殖亲本的杂种是无融合生殖的。克隆生殖可以使F1个体延续并产生无性种。或者，杂种可以杂交和回交以产生杂种群或与亲本以外的物种杂交。在北美东部，该属的丰富的已发表名称和普遍的分类混乱无疑至少部分地是由于无融合生殖和杂交的相互作用。本文根据一种无融合生殖的杂种小种（非正式地命名为A.并与另一种Amelanchier无融合生殖体A.光滑。
Apomixis and hybridization together contribute to taxonomic complexity in Amelanchier. Hybridization combines genetically divergent genomes and spawns new forms that apomixis perpetuates. Apomixis is aposporous, facultative, and pseudogamous in the genus, and apomicts are generally polyploid, pollen fertile, and pollinated by generalists. That gene flow actually occurs is empirically evident. As apomixis is genetically dominant over sexuality, hybrids involving at least one apomictic parent are apomictic. Clonal reproduction may thus perpetuate Fl individuals and generate agamospecies. Alternatively hybrids may interbreed and backcross to create hybrid swarms or cross with species other than the parents. In eastern North America, the abundance of published names and general taxonomic confusion in the genus doubtless result at least in part from this interplay of apomixis and hybridization. The roles of apomixis and hybridization in diversification within Amelanchier are examined in light of new data about breeding system of an apomictic, hybrid microspecies, informally named A. ''erecta'' and its formation of a hybrid swarm with another Amelanchier apomict, A. laevis.