Dipartimento di Scienze Agronomiche e Genetica Vegetale Agraria, Università degli Studi di Sassari, Via de Nicola, 07100, Sassari, Italy.
Theor Appl Genet. 2010 Sep;121(5):829-43. doi: 10.1007/s00122-010-1353-2. Epub 2010 May 21.
This study focuses on the expansion of Phaseolus vulgaris in Europe. The pathways of distribution of beans into and across Europe were very complex, with several introductions from the New World that were combined with direct exchanges between European and other Mediterranean countries. We have analyzed here six chloroplast microsatellite (cpSSR) loci and two unlinked nuclear loci (for phaseolin types and Pv-shatterproof1). We have assessed the genetic structure and level of diversity of a large collection of European landraces of P. vulgaris (307) in comparison to 94 genotypes from the Americas that are representative of the Andean and Mesoamerican gene pools. First, we show that most of the European common bean landraces (67%) are of Andean origin, and that there are no strong differences across European regions for the proportions of the Andean and Mesoamerican gene pools. Moreover, cytoplasmic diversity is evenly distributed across European regions. Secondly, the cytoplasmic bottleneck that was due to the introduction of P. vulgaris into the Old World was very weak or nearly absent. This is in contrast to evidence from nuclear analyses that have suggested a bottleneck of greater intensity. Finally, we estimate that a relatively high proportion of the European bean germplasm (about 44%) was derived from hybridization between the Andean and Mesoamerican gene pools. Moreover, although hybrids are present everywhere in Europe, they show an uneven distribution, with high frequencies in central Europe, and low frequencies in Spain and Italy. On the basis of these data, we suggest that the entire European continent and not only some of the countries therein can be regarded as a secondary diversification center for P. vulgaris. Finally, we outline the relevance of these inter-gene pool hybrids for plant breeding.
本研究聚焦于菜豆在欧洲的扩张。豆类传入和传播到欧洲的途径非常复杂，有多次从新大陆引入的情况，同时也有欧洲与其他地中海国家之间的直接交流。我们在这里分析了六个叶绿体微卫星 (cpSSR) 位点和两个不连锁的核基因座（用于 phaseolin 类型和 Pv-shatterproof1）。我们评估了一个大型欧洲地方品种菜豆（307 个）群体的遗传结构和多样性水平，并与来自美洲的 94 个基因型进行了比较，这些基因型代表了安第斯和中美洲基因库。首先，我们表明，大多数欧洲普通菜豆地方品种（67%）起源于安第斯山脉，而安第斯山脉和中美洲基因库的比例在欧洲各地区之间没有明显差异。此外，细胞质多样性在整个欧洲地区均匀分布。其次，由于菜豆引入旧世界而导致的细胞质瓶颈非常微弱或几乎不存在。这与核分析的证据形成对比，核分析表明存在更强烈的瓶颈。最后，我们估计，欧洲豆类种质资源的相对较高比例（约 44%）来自安第斯山脉和中美洲基因库之间的杂交。此外，尽管杂种在欧洲各地都存在，但它们的分布不均匀，中欧的频率较高，而西班牙和意大利的频率较低。基于这些数据，我们认为整个欧洲大陆，而不仅仅是其中的一些国家，可以被视为菜豆的次级多样化中心。最后，我们概述了这些基因库间杂种在植物育种中的相关性。
