白菜抗根肿病分子标记开发与种质资源鉴定

Development of molecular markers for clubroot resistanceand identification of germplasm resources for Brassica rapa

【目的】开发可在白菜中高效鉴定根肿病抗病基因的KASP(Kompetitive Allele Specific PCR)标记,并利用这些标记研究大量白菜资源材料中抗病基因分布规律。【方法】根据已克隆白菜抗根肿病基因信息,使用Primer3与DNAMAN开发KASP标记。利用代表性的62份白菜材料组成测试群体筛选标记,获得高可靠性标记,对862份白菜资源进行抗病基因型鉴定。【结果】从4个已克隆的抗根肿病基因(CRa、CRb、CRd、Crr1a)内开发并筛选出6个基因特异性KASP标记。白菜资源中鉴定出105份含有抗病基因型材料,其中芜菁与油用白菜占70.48%;CRa分布最广,占所有抗病材料的58.09%;含有2个或2个以上抗病基因的材料16份。【结论】获得6个稳定可靠的抗根肿病基因特异性KASP标记。CRa分布最广,筛选出同时携带多个抗根肿病基因的资源材料。

【Objective】To develop KASP(Kompetitive Allele Specific PCR)marker for efficiently identifying CR(clubroot resistance)genes in cabbage B.rapa germplasms by using KASP markers to explore the distribution of clubroot resistant genes in germplasm collected with a large number of B.rapa accessions.【Methods】Based on the information of cloned clubroot resistance genes previously,KASP markers were developed using Primer 3 and DNAMAN and the highly reliable markers were screened using a representative population containing 62 B.rapa varieties.Then,these available markers were used to genotype the 862 B.rapa resource population for disease resistance.【Results】Based on four cloned disease resistance genes(CRa,CRb,CRd,Crr1a),six gene-specific KASP markers related to clubroot disease resistance were developed and screened.Among the 862 B.rapa germplasm accessions,105 accessions containing clubroot resistance genes were identified.Turnip and turnip rape accounted for 70.48%.CRa was found to be the clubroot resistance gene carried by most accessions among B.rapa germplasm resources,which accounted for 58.09%of all disease resistant materials.Additionally,we found 16 accessions that contained two or more resistance genes.【Conclusion】In this study,six stable and reliable gene-specific KASP markers were developed.CRa was found to be the clubroot resistance genes carried by most accessions among the four CR genes.Importantly,a few germplasm resources were identified that carried multiple clubroot resistance genes.