Department of Agronomy and Plant Genetics, University of Minnesota, St Paul, MN 55108, USA.
Phytopathology. 2010 Jan;100(1):80-4. doi: 10.1094/PHYTO-100-1-0080.
Septoria speckled leaf blotch (SSLB), caused by Septoria passerinii Sacc., and net form net blotch (NB), caused by Pyrenophora teres f. teres Drechsler, are fungal diseases that decrease the yields of barley in the Upper Midwest. An effective way to manage these diseases is to plant resistant cultivars. To characterize the genetics of resistance to both pathogens, two advanced barley breeding lines, one resistant to NB (M120) and another resistant to SSLB (Sep2-72), were crossed, creating a population of 115 recombinant inbred lines. The two parents and the population were evaluated in three greenhouse seedling assays for each pathogen and for simple-sequence repeat and diversity arrays technology markers. Composite interval mapping revealed two major quantitative trait loci (QTL) associated with NB on chromosome 6H, located in bins 2 and 6. The QTL located in bin 6 explained 19 to 48% of the phenotypic variation and the QTL located in bin 2 explained 25 to 44% of the phenotypic variation. A new locus for resistance to SSLB, Rsp4, was identified on chromosome 6H, located in bins 3 to 4. Mapping these genes in elite breeding germplasm will accelerate the development and utilization of marker-assisted selection to enhance resistance to these diseases.
叶斑条锈病（SSLB）由 Septoria passerinii Sacc.引起，网斑病（NB）由 Pyrenophora teres f. teres Drechsler 引起，这两种真菌病害都会降低中西部高海拔地区大麦的产量。种植抗性品种是管理这些病害的有效方法。为了研究这两种病原菌的抗性遗传特性，我们将一个对 NB（M120）具有抗性，另一个对 SSLB（Sep2-72）具有抗性的两个先进的大麦育种系进行杂交，创造了一个由 115 个重组自交系组成的群体。我们对这两个亲本和群体进行了三个温室幼苗测定，每个病原菌和简单序列重复和多样性阵列技术标记。复合区间作图揭示了与 NB 相关的两个主要数量性状位点（QTL），位于 6H 染色体的 2 号和 6 号-bin 中。位于 bin 6 中的 QTL 解释了 19%到 48%的表型变异，位于 bin 2 中的 QTL 解释了 25%到 44%的表型变异。在 6H 染色体上的 bin 3 到 4 之间，我们发现了一个与 SSLB 抗性相关的新基因 Rsp4。在优秀的育种种质中定位这些基因将加速标记辅助选择的发展和利用，以提高对这些病害的抗性。
