Kashyap Prem Lal, Kumar Sudheer, Tripathi Rahul, Kumar Ravi Shekhar, Jasrotia Poonam, Singh Devendra Pal, Singh Gyanendra Pratap
ICAR-Indian Institute of Wheat and Barley Research (IIWBR), Karnal, India.
Front Microbiol. 2019 May 15;10:1072. doi: 10.3389/fmicb.2019.01072. eCollection 2019.
(Pers.) Roussel (UST) causes loose smut of wheat account for considerable grain yield losses globally. For effective management, knowledge of its genetic variability and population structure is a prerequisite. In this study, UST isolates sampled from four different wheat growing zones of India were analyzed using the second largest subunit of the RNA polymerase II () and a set of sixteen neutral simple sequence repeats (SSRs) markers. Among the 112 UST isolates genotyped, 98 haplotypes were identified. All the isolates were categorized into two groups ( = 2), each consisting of isolates from different sampling sites, on the basis of unweighted paired-grouping method with arithmetic averages (UPGMA) and the Bayesian analysis of population structure. The positive and significant index of association (I = 1.169) and standardized index of association (rBar = 0.075) indicate population is of non-random mating type. Analysis of molecular variance showed that the highest variance component is among isolates (91%), with significantly low genetic differentiation variation among regions (8%) (F = 0.012). Recombination (R = 0) was not detected. The results showed that UST isolates have a clonal genetic structure with limited genetic differentiation and human arbitrated gene flow and mutations are the prime evolutionary processes determining its genetic structure. These findings will be helpful in devising management strategy especially for selection and breeding of resistant wheat cultivars.
（Pers.）鲁塞尔黑粉菌（UST）引发的小麦散黑穗病在全球范围内造成了相当大的粮食产量损失。为了进行有效管理，了解其遗传变异性和种群结构是一个先决条件。在本研究中，使用RNA聚合酶II的第二大亚基（）和一组16个中性简单序列重复（SSR）标记对从印度四个不同小麦种植区采集的UST分离株进行了分析。在112个进行基因分型的UST分离株中，鉴定出了98个单倍型。根据非加权算术平均法（UPGMA）和种群结构的贝叶斯分析，所有分离株被分为两组（K = 2），每组由来自不同采样地点的分离株组成。关联的正向显著指数（I = 1.169）和标准化关联指数（rBar = 0.075）表明该种群为非随机交配类型。分子方差分析表明，最高方差成分存在于分离株之间（91%），区域间的遗传分化变异显著较低（8%）（F = 0.012）。未检测到重组（R = 0）。结果表明，UST分离株具有克隆遗传结构，遗传分化有限，人为介导的基因流动和突变是决定其遗传结构的主要进化过程。这些发现将有助于制定管理策略，特别是在抗性小麦品种的选择和育种方面。
