大白菜抗根肿病基因CRb的分子标记验证与种质资源筛选

Identification of Molecular Markers for Clubroot Disease Resistant Gene CRb and Screening of Germplasm Resources of Chinese Cabbage

大白菜根肿病是一种严重影响大白菜生长的土传病害,已成为大白菜的重要病害之一。CRb基因是抗大白菜根肿病的重要基因。本研究对已发表的6个CRb分子标记进行筛选,获得1个与CRb紧密连锁的共显性标记TCR05。该标记在抗病纯和材料中产生279 bp的PCR扩增片段,在感病材料中产生250 bp的PCR片段,在抗病杂合材料中同时产生279 bp和250 bp的PCR片段。利用TCR05对24份育种材料进行筛选,均含CRb基因,其中8份为纯合体,16份为杂合体,筛选结果与田间鉴定结果基本一致。

Clubroot disease,caused by Plasmodiophora brassicae,is one of soil- borne disease seriously affecting the growth and development of Chinese cabbage（ Brassica pekinensis L.） and has become one of the most serious diseases. Gene CRb is one of the most important gene against to clubroot disease in Chinese cabbage. In this research,TCR05,an effective codominant marker closely linked to CRb,was identified from 6published molecular markers. The marker owned a 279- bp PCR amplification fragment in the resistant lines,a 250- bp fragment in the susceptible lines and both 279- bp and 250- bp fragments in the heterozygous combinations. TCR05 was used to screen 24 germplasms. It was proved that they all contained gene CRb,8were homozygous and the others were heterozygous. The results were in accordance with the field test results.