Chhetri Mumta, Bariana Harbans, Kandiah Pakeerathan, Bansal Urmil
All authors: University of Sydney Plant Breeding Institute-Cobbitty, Faculty of Agriculture and Environment, PMB 4011, Narellan, NSW2567, Australia.
Phytopathology. 2016 Dec;106(12):1530-1534. doi: 10.1094/PHYTO-04-16-0182-R. Epub 2016 Sep 26.
The quantitative trait loci QYr.sun-3BS and QYr.sun-4DL were identified in the W195/BTSS recombinant inbred line (RIL) population in a previous study. QYr.sun-3BS explained 34 to 59% phenotypic variation in stripe rust response. We evaluated parental genotypes at different growth stages and temperature regimes to detect the critical stage for expression of QYr.sun-3BS. W195 expressed low infection type (IT) ;1C at the fourth leaf stage, when incubated at 21 ± 2°C and the alternate parent BTSS was susceptible (IT 3). Monogenic segregation for stripe rust response was observed among the RIL population at the fourth leaf stage and the underlying locus was temporarily named YrW195. YrW195 corresponded to QYr.sun-3BS. Since no previously designated stripe rust resistance genes that expresses at and after the fourth leaf stage was mapped in this region, YrW195 was formally named Yr58. Genotyping with Yr46-linked markers indicated the presence of Yr46 in W195, which corresponded to QYr.sun-4DL. The RILs carrying Yr58 and Yr46 singly produced IT 23C and IT 3, respectively, and those carrying both genes produced IT ;1C indicating the enhancement of Yr58 expression by Yr46. The absence of Yr58-linked alleles of markers sun533 and sun476 in 74 of the 76 wheat cultivars demonstrated their usefulness for marker-assisted selection.
在之前的一项研究中，在W195/BTSS重组自交系（RIL）群体中鉴定出数量性状位点QYr.sun-3BS和QYr.sun-4DL。QYr.sun-3BS解释了条锈病抗性中34%至59%的表型变异。我们评估了亲本在不同生长阶段和温度条件下的基因型，以检测QYr.sun-3BS表达的关键阶段。当在21±2°C下培养时，W195在第四叶期表现出低感染类型（IT）；1C，而其替代亲本BTSS易感（IT 3）。在第四叶期的RIL群体中观察到条锈病抗性的单基因分离，潜在位点暂时命名为YrW195。YrW195与QYr.sun-3BS相对应。由于此前没有在该区域定位到在第四叶期及之后表达的条锈病抗性基因，YrW195被正式命名为Yr58。用与Yr46连锁的标记进行基因分型表明W195中存在Yr46，它与QYr.sun-4DL相对应。单独携带Yr58和Yr46的RIL分别产生IT 23C和IT 3，而同时携带这两个基因的RIL产生IT；1C，表明Yr46增强了Yr58的表达。在76个小麦品种中的74个品种中未检测到标记sun533和sun476的Yr58连锁等位基因，这表明它们可用于标记辅助选择。
