Yellow rust, caused by Puccinia striiformis f. sp. tritici (Pst), is economically one of the most important diseases of wheat in India and worldwide. During four wheat-growing seasons (2015-19), a total of 951 yellow rust samples collected from farmers’ fields (n = 602) and trap plot nurseries (n = 349) were analyzed for virulence on 30 differentials. From this analysis, 11 distinct Pst pathotypes were identified. The virulence pattern of these pathotypes was also tested on 14 Avocet near-isogenic lines (NILs) and Avocet S. None of the pathotypes were virulent to Yr5, Yr10, Yr15, Yr16, Yr24, Yr32, and YrSP. Pathotype 46S119 (46E159) was most prevalent and widely distributed in all the areas and its overall frequency was maximum (56.2%) followed by 110S119 (110E159, 31.9%). However, the frequency of 46S119 has decreased gradually from 62.0% (2015-16) to 48.4% (2018-19). Pathotype 238S119 (238E159) being the most virulent among the identified pathotypes, was detected in 6.8% of samples. Each of the remaining pathotypes was identified in <5% of the samples. Genetic diversity among eleven pathotypes was assessed using novel 89 SSR primer-pairs out of which 24 primers showed polymorphism. Finally, 69 alleles were detected across the loci with an average of 2.87 alleles per locus. Polymorphic information content (PIC) value was in the range from 0.28 to 0.68, with a mean of 0.47. Expected heterozygosity was in the 0.34 to 0.73 range, with a mean of 0.56. Cluster analysis based on both avirulence/virulence pattern and SSR profile categorized the identified pathotypes into two major clades. Generated information will potentially be helpful in rust resistance breeding and deployment of resistant cultivars in yellow rust-prone areas.

黄锈病，由Puccinia striiformis f.引起。sp. 小麦( Pst ) 是印度和世界范围内小麦最重要的经济病害之一。在四个小麦生长季节（2015-19 年）期间，从农田（n = 602）和诱捕小区苗圃（n = 349）收集的总共 951 个黄锈病样本分析了 30 个差异的毒力。从该分析中，确定了 11 种不同的Pst病理类型。还在 14 个 Avocet 近等基因系 (NIL) 和 Avocet S 上测试了这些致病型的毒力模式。没有一种致病型对Yr5、Yr10、Yr15、Yr16、Yr24、Yr32和YrSP 具有毒性. 病理型46S119（46E159）在所有地区最普遍，分布最广，其总频率最高（56.2%），其次是110S119（110E159，31.9%）。然而，46S119 的频率已经从 62.0%（2015-16 年）逐渐下降到 48.4%（2018-19 年）。致病型 238S119 (238E159) 是已鉴定的致病型中毒性最强的，在 6.8% 的样本中检测到。在 <5% 的样本中鉴定了每种剩余的病理类型。使用新的 89 个 SSR 引物对评估 11 种病理类型之间的遗传多样性，其中 24 个引物显示多态性。最后，在整个基因座上检测到 69 个等位基因，每个基因座平均有 2.87 个等位基因。多态信息内容（PIC) 值在 0.28 到 0.68 的范围内，平均值为 0.47。预期杂合度在 0.34 至 0.73 范围内，平均值为 0.56。基于无毒力/毒力模式和 SSR 谱的聚类分析将确定的病理类型分为两个主要进化枝。生成的信息可能有助于黄锈病易发地区的抗锈病育种和抗病品种的部署。