Molnar S J, James L E, Kasha K J
Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, ON.
Genome. 2000 Apr;43(2):224-31.
A doubled haploid barley (Hordeum vulgare L.) population that was created from a cross between cultivars 'Léger' and 'CI 9831' was characterized by RAPD (random amplified polymorphic DNA) markers for resistance to isolate WRS857 of Pyrenophora teres Drechs. f. sp. maculata Smedeg., the causal agent of the spot form of net blotch. Resistance, which initially appeared to be conferred by a single gene from the approximate 1:1 (resistant : susceptible) segregation ratio of the doubled-haploid (DH) progeny, was found to be associated with three different genomic regions by RAPD analysis. Of 500 RAPD random primers that were screened against the parents, 195 revealed polymorphic bands, seven showed an association to the resistance in bulks, and these seven markers were mapped to three unlinked genomic regions. Two of these regions, one of which was mapped to chromosome 2, have major resistance genes. The third region has some homology to the chromosome 2 region. This study demonstrates the simultaneous location of markers for more than one gene governing a trait by using RAPD and bulked segregant analysis (BSA).
通过将品种“Léger”和“CI 9831”杂交构建了一个双单倍体大麦（Hordeum vulgare L.）群体，利用随机扩增多态性DNA（RAPD）标记对其进行了特征分析，以检测对网斑病菌斑点型病原菌Pyrenophora teres Drechs. f. sp. maculata Smedeg.的分离株WRS857的抗性。抗性最初似乎由一个单基因控制，这是根据双单倍体（DH）后代大约1:1（抗性:感病）的分离比例判断的，但通过RAPD分析发现抗性与三个不同的基因组区域相关。在针对亲本筛选的500个RAPD随机引物中，195个显示出多态性条带，7个在混合群体中显示出与抗性相关，并且这7个标记被定位到三个不连锁的基因组区域。其中两个区域，其中一个被定位到2号染色体，含有主要抗性基因。第三个区域与2号染色体区域有一些同源性。本研究通过使用RAPD和混合分离群体分析（BSA）证明了控制一个性状的多个基因的标记可以同时定位。
