Zhang Z W, Ma G J, Zhao J, Markell S G, Qi L L
Department of Agronomy, Inner Mongolia Agricultural University, Huhhot, 010019, Inner Mongolia, China.
Department of Plant Pathology, North Dakota State University, Fargo, ND, 58108, USA.
Theor Appl Genet. 2017 Jan;130(1):29-39. doi: 10.1007/s00122-016-2786-z. Epub 2016 Sep 27.
A new downy mildew resistance gene, Pl , was identified from wild Helianthus annuus accession PI 435414, introduced to confection sunflower, and genetically mapped to linkage group 4 of the sunflower genome. Wild Helianthus annuus accession PI 435414 exhibited resistance to downy mildew, which is one of the most destructive diseases to sunflower production globally. Evaluation of the 140 BCF families derived from the cross of CMS CONFSCLB1 and PI 435414 against Plasmopara halstedii race 734 revealed that a single dominant gene controls downy mildew resistance in the population. Bulked segregant analysis conducted in the BCF population with 860 simple sequence repeat (SSR) markers indicated that the resistance derived from wild H. annuus was associated with SSR markers located on linkage group (LG) 4 of the sunflower genome. To map and tag this resistance locus, designated Pl , 140 BCF individuals were used to construct a linkage map of the gene region. Two SSR markers, ORS963 and HT298, were linked to Pl within a distance of 4.7 cM. After screening 27 additional single nucleotide polymorphism (SNP) markers previously mapped to this region, two flanking SNP markers, NSA_003564 and NSA_006089, were identified as surrounding the Pl gene at a distance of 0.6 cM from each side. Genetic analysis indicated that Pl is different from Pl , which had previously been mapped to LG4, but is closely linked to Pl . This new gene is highly effective against the most predominant and virulent races of P. halstedii currently identified in North America and is the first downy mildew resistance gene that has been transferred to confection sunflower. The selected resistant germplasm derived from homozygous BCF progeny provides a novel gene for use in confection sunflower breeding programs.
从野生向日葵种质PI 435414中鉴定出一个新的霜霉病抗性基因Pl ，该基因已被导入食用向日葵，并在向日葵基因组的第4连锁群上进行了遗传定位。野生向日葵种质PI 435414对霜霉病表现出抗性，霜霉病是全球向日葵生产中最具破坏性的病害之一。对由CMS CONFSCLB1与PI 435414杂交产生的140个BCF家系进行针对向日葵霜霉菌734小种的评估，结果表明，该群体中霜霉病抗性由一个显性基因控制。利用860个简单序列重复（SSR）标记对BCF群体进行混合分组分析，结果表明，来自野生向日葵的抗性与位于向日葵基因组第4连锁群（LG）上的SSR标记相关。为了对这个抗性位点（命名为Pl ）进行定位和标记，使用140个BCF个体构建了该基因区域的连锁图谱。两个SSR标记ORS963和HT298与Pl 紧密连锁，距离为4.7厘摩。在筛选了另外27个先前定位到该区域的单核苷酸多态性（SNP）标记后，确定了两个侧翼SNP标记NSA_003564和NSA_006089，它们分别位于Pl 基因两侧0.
