Quantitative trait loci conferring blast resistance in hexaploid wheat at adult plant stage
Quantitative trait loci conferring blast resistance in hexaploid wheat at adult plant stage
复制标题
DOI：
10.1111/ppa.13278
复制
发表时间：
2020-09-30
期刊：
影响因子：
2.7
通讯作者：
Nicholson, Paul
中科院分区：
文献类型：
--
作者：
Ferreira, Jessica Rosset;Torres, Gisele Abigail Montan;Nicholson, Paul
稻瘟病是一种严重危害热带和亚热带小麦生产的病害。最具破坏性的症状发生在麦穗上。受感染的穗由于部分或全部不育而变白，产生小而起皱的籽粒。病害的高发病压力导致显著的产量损失。本研究旨在鉴定小麦抽穗期抗稻瘟病的数量性状位点。从BRS 209（感病）和CBFusarium ENT 014（抗性，携带2NS易位）之间的杂交开发双单倍体群体。构建了一张包含5,381个分子标记的连锁图，并采用包含性复合区间作图法进行QTL定位。4个QTL定位在两个MoT分离物。在2AS染色体上发现的主效QTL平均解释了接种后9天穗漂白的84.0%的表型变异，并加强了2NS易位的效力。2NS标记与2AS远侧区的标记之间存在着重叠，这一结果可以解释为什么一些携带VENTRIUP/LN 2标记的品系对该病的反应不一致。还鉴定了5 B和7 B染色体上的QTL。有两种机制的阻力被假设：过敏反应和抵抗宿主组织的殖民化。由此开发的KASP标记和QTL区域中分配的简单重复序列（SSR）可用于未来小麦抗稻瘟病品种的开发。
Blast disease, caused by theMagnaporthe oryzae Triticumpathotype (MoT), is a major concern for wheat production in tropical and subtropical regions. The most destructive symptoms occur in wheat spikes. Infected spikes become bleached due to partial or total sterility, producing small and wrinkled grains. High disease pressure of the disease results in significant yield losses. This study aimed to identify wheat quantitative trait loci (QTLs) conferring resistance to blast disease at the heading stage. A doubled-haploid population was developed from the cross between BRS 209 (susceptible) and CBFusarium ENT014 (resistant, carrying the 2NS translocation). A linkage map was constructed containing 5,381 molecular markers and the inclusive composite interval mapping method was employed for QTL detection. Four QTLs were mapped in response to two MoT isolates. The major QTL identified on the 2AS chromosome explained an average of 84.0% of the phenotypic variation for spike bleaching at 9 days postinoculation and reinforces the potency of the 2NS translocation. Recombination between the distal region of chromosome 2AS and the 2NS marker was found. These results could explain why some lines carrying theVENTRIUP/LN2marker have a variable reaction to the disease. QTLs on 5B and 7B chromosomes were also identified. Two mechanisms of resistance were hypothesized: the hypersensitive response and resistance to colonization of host tissues. The KASP markers thus developed and simple sequence repeats (SSRs) allocated in QTL regions can be used in the future for the development of wheat blast-resistant cultivars.