Institute of Botany, University of Liège, Liège, Belgium Faculté des Sciences, Université Libre de Bruxelles, Bruxelles, Belgium.
J Evol Biol. 2011 Mar;24(3):630-44. doi: 10.1111/j.1420-9101.2010.02198.x. Epub 2010 Dec 22.
The main factor of differentiation at six nuclear microsatellite and seven cpDNA loci in Salicornia from the Mediterranean and Atlantic coasts of France is cytotypic identity, suggesting the presence of a strong reproductive barrier among sympatric cytotypes. Within cytotypes, a substantial proportion of the differentiation between species is due to confounded phylogeographic signal. Conspecific individuals tend to be significantly more related than individuals from different species at the population scale, but mean kinship coefficients among pairs of conspecific and nonconspecific individuals from different populations are not significantly different, suggesting the absence of reproductive isolation among species of the same cytotype. The observed association between morphology and genetic variation within populations would thus result from the selfing mating system (F(is)) = 0.70) generating substantial linkage within the genome, linkage that would quickly disappear among unrelated individuals from different populations. Salicornia species thus function as a network of inbred populations, strongly challenging taxonomic concepts.
在法国地中海和大西洋沿岸的盐角草中，6 个核微卫星和 7 个 cpDNA 位点的主要分化因素是细胞型同一性，表明在同域细胞型之间存在强大的生殖障碍。在细胞型内，物种之间的大量分化归因于混淆的系统地理学信号。在种群尺度上，同种个体之间的亲缘关系往往比不同物种的个体更为密切，但来自不同种群的同种和非同种个体之间的平均亲缘系数没有显著差异，这表明同一细胞型的物种之间不存在生殖隔离。因此，在种群内观察到的形态和遗传变异之间的关联是由于自交交配系统（F(is) = 0.70）在基因组内产生了大量的连锁，这种连锁在来自不同种群的无关个体中很快就会消失。因此，盐角草物种构成了一个近亲繁殖种群的网络，强烈挑战了分类学概念。
