Department of Botany, West Bengal State University, Kolkata, 700126, India.
Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, Raleigh, NC, 27607, USA.
Sci Rep. 2018 Mar 13;8(1):4429. doi: 10.1038/s41598-018-22192-1.
The population structure of the Phytophthora infestans populations that caused the recent 2013-14 late blight epidemic in eastern India (EI) and northeastern India (NEI) was examined. The data provide new baseline information for populations of P. infestans in India. A migrant European 13_A2 genotype was responsible for the 2013-14 epidemic, replacing the existing populations. Mutations have generated substantial sub-clonal variation with 24 multi-locus genotypes (MLGs) found, of which 19 were unique variants not yet reported elsewhere globally. Samples from West Bengal were the most diverse and grouped alongside MLGs found in Europe, the UK and from neighbouring Bangladesh but were not linked directly to most samples from south India. The pathogen population was broadly more aggressive on potato than on tomato and resistant to the fungicide metalaxyl. Pathogen population diversity was higher in regions around the international borders with Bangladesh and Nepal. Overall, the multiple shared MLGs suggested genetic contributions from UK and Europe in addition to a sub-structure based on the geographical location within India. Our data indicate the need for improved phytosanitary procedures and continuous surveillance to prevent the further introduction of aggressive lineages of P. infestans into the country.
对导致印度东部（EI）和东北部（NEI）2013-14 年晚疫病流行的致病疫霉种群结构进行了研究。该数据为印度境内的致病疫霉种群提供了新的基线信息。一个来自欧洲的移民 13_A2 基因型是造成 2013-14 年流行的原因，取代了现有的种群。突变产生了大量的亚克隆变异，共发现 24 种多位点基因型（MLGs），其中 19 种是尚未在全球其他地方报道过的独特变体。来自西孟加拉邦的样本最多样化，与在欧洲、英国和邻国孟加拉国发现的 MLGs 聚在一起，但与来自印度南部的大多数样本没有直接联系。与番茄相比，该病原菌在马铃薯上的攻击性更强，对杀菌剂甲霜灵有抗性。与孟加拉国和尼泊尔接壤的边境地区的病原菌种群多样性更高。总的来说，多个共享的 MLGs 表明，除了基于印度境内地理位置的亚结构外，英国和欧洲也有遗传贡献。我们的数据表明，需要改进植物检疫程序和持续监测，以防止更具攻击性的疫霉菌系进一步传入该国。
