Two Clubroot-Resistance Genes,Rcr3andRcr9wa, Mapped inBrassica rapaUsing Bulk Segregant RNA Sequencing
Two Clubroot-Resistance Genes,Rcr3andRcr9wa, Mapped inBrassica rapaUsing Bulk Segregant RNA Sequencing
复制标题
DOI：
10.3390/ijms21145033
复制
发表时间：
2020-07-01
影响因子：
5.6
通讯作者：
Yu, Fengqun
中科院分区：
文献类型：
--
作者：
Karim, Md Masud;Dakouri, Abdulsalam;Yu, Fengqun
遗传抗性被广泛用于控制芸苔属作物中的根肿病（芸苔根肿菌），但最近在加拿大大草原上的油菜（甘蓝型油菜）上发现了新的致病型。需要对最流行的致病型（3 H，基于加拿大丛根分化系统）和新致病型有效的抗性。甘蓝型油菜（Brassica rapa）的BC（1）系96-6990-2（根肿病抗性来源于芜菁品种'Waaslander'）与感病的双单倍体系ACDC杂交，对3 H和5X的抗性表现1：1分离。首先利用BSR-Seq法对Rcr 3基因进行了多态性分析，然后利用竞争等位基因特异性PCR对Rcr 3基因进行了定位。通过针对B的参考基因组组装短读段来鉴定DNA变体。Rcr 3定位在A08染色体上。其侧翼为单核苷酸多态性（SNP）标记（A90_A08_SNP_M12和M16），在10.00和10.23 Mb之间，间隔为231.6 Kb。Rcr 3区间有32个基因。三个基因（Bra 020951、Bra 020974和Bra 020979）被注释了抗病机制，它们是Rcr 3的潜在候选基因。另一个抗性基因，命名为Rcr 9（wa），用于对致病型5X的抗性，使用通过Rcr 3的BSR-Seq鉴定的SNP位点，用10.85和11.17 Mb之间的侧翼标记（A90_A08_SNP_M28和M79）作图。Rcr 9（wa）区间共有44个基因，其中3个（Bra 020827、Bra 020828、Bra 020814）被注释为免疫系统过程相关基因，是Rcr 9（wa）的潜在候选基因。
Genetic resistance is widely used to manage clubroot (Plasmodiophora brassicae) in brassica crops, but new pathotypes have recently been identified on canola (Brassica napus) on the Canadian prairies. Resistance effective against both the most prevalent pathotype (3H, based on the Canadian Clubroot Differential system) and the new pathotypes is needed. BC(1)plants ofBrassica rapafrom a cross of line 96-6990-2 (clubroot resistance originating from turnip cultivar 'Waaslander') and a susceptible doubled-haploid line, ACDC, exhibited a 1:1 segregation for resistance against pathotypes 3H and 5X. A resistance gene designated asRcr3was mapped initially based on the percentage of polymorphic variants using bulked segregant RNA sequencing (BSR-Seq) and further mapped using Kompetitive Allele Specific PCR. DNA variants were identified by assembling short reads against a reference genome ofB. rapa.Rcr3was mapped into chromosome A08. It was flanked by single nucleotide polymorphisms (SNP) markers (A90_A08_SNP_M12 and M16) between 10.00 and 10.23 Mb, in an interval of 231.6 Kb. There were 32 genes in theRcr3interval. Three genes (Bra020951,Bra020974, andBra020979) were annotated with disease resistance mechanisms, which are potential candidates forRcr3. Another resistance gene, designated asRcr9(wa),for resistance to pathotype 5X was mapped, with the flanking markers (A90_A08_SNP_M28 and M79) between 10.85 and 11.17 Mb using the SNP sites identified through BSR-Seq forRcr3. There were 44 genes in theRcr9(wa)interval, three of which (Bra020827, Bra020828, Bra020814) were annotated as immune-system-process related genes, which are potential candidates forRcr9(wa).