DIVAPRA Plant Genetics and Breeding, University of Torino, via L. da Vinci 44, 10095, Grugliasco (Turin), Italy.
Theor Appl Genet. 2009 Dec;120(1):59-70. doi: 10.1007/s00122-009-1159-2. Epub 2009 Sep 29.
The genome organization of globe artichoke (Cynara cardunculus var. scolymus), unlike other species belonging to Asteraceae (=Compositae) family (i.e. sunflower, lettuce and chicory), remains largely unexplored. The species is highly heterozygous and suffers marked inbreeding depression when forced to self-fertilize. Thus a two-way pseudo-testcross represents the optimal strategy for linkage analysis. Here, we report linkage maps based on the progeny of a cross between globe artichoke (C. cardunculus var. scolymus) and cultivated cardoon (C. cardunculus var. altilis). The population was genotyped using a variety of PCR-based marker platforms, resulting in the identification of 708 testcross markers suitable for map construction. The male map consisted of 177 loci arranged in 17 major linkage groups, spanning 1,015.5 cM, while female map was built with 326 loci arranged into 20 major linkage groups, spanning 1,486.8 cM. The presence of 84 loci shared between these maps and those previously developed from a cross within globe artichoke allowed for map alignment and the definition of 17 homologous linkage groups, corresponding to the haploid number of the species. This will provide a favourable property for QTL scanning; furthermore, as 25 mapped markers (8%) correspond to coding regions, it has an additional value as functional map and might represent an important genetic tool for candidate gene studies in globe artichoke.
与其他菊科（即向日葵、生菜和菊苣）物种不同，朝鲜蓟（Cynara cardunculus var. scolymus）的基因组组织在很大程度上仍未被探索。该物种高度杂合，自交时会受到明显的近交衰退。因此，双向假测交代表了连锁分析的最佳策略。在这里，我们报告了基于朝鲜蓟（C. cardunculus var. scolymus）和栽培朝鲜蓟（C. cardunculus var. altilis）杂交后代的连锁图谱。该群体使用多种基于 PCR 的标记平台进行了基因型分析，鉴定出了 708 个适合图谱构建的测试交叉标记。雄性图谱由 177 个位于 17 个主要连锁群的位点组成，覆盖了 1015.5 cM，而雌性图谱由 326 个位于 20 个主要连锁群的位点组成，覆盖了 1486.8 cM。这些图谱与先前从朝鲜蓟内部杂交中构建的图谱之间存在 84 个共享的位点，这使得图谱可以进行比对，并定义了 17 个同源连锁群，对应于该物种的单倍体数量。这将为 QTL 扫描提供有利条件；此外，由于 25 个映射标记（8%）对应于编码区域，因此它还具有功能图谱的额外价值，并可能成为朝鲜蓟候选基因研究的重要遗传工具。
