Ling Kai-Shu, Wintermantel William M, Bledsoe Michael
U.S. Department of Agriculture-Agricultural Research Service, U.S. Vegetable Laboratory, 2700 Savannah Highway, Charleston, SC 29414.
U.S. Department of Agriculture-Agricultural Research Service, 1636 E. Alisal Street, Salinas, CA 93905.
Plant Dis. 2008 Dec;92(12):1683-1688. doi: 10.1094/PDIS-92-12-1683.
In just a few short years, pepino mosaic disease has quickly become endemic in greenhouse tomatoes around the world. Although three genotypes of Pepino mosaic virus (PepMV) were identified in the United States, genetic composition of PepMV in greenhouse tomato crops in North America has not been determined. In this study, genetic variability and population structure of PepMV were evaluated through nucleotide sequence comparison and phylogenetic analysis of two genomic regions (helicase domain and TGB2-3) derived from 91 cDNA clones that were derived from 31 field-collected samples. These samples were collected from several major greenhouse tomato facilities in five states in the United States and two provinces in Canada. All four major genotypes of PepMV (EU, US1, US2, and CH2) were found in North America. Three distinct genotypes (EU, US1, and US2) were found in mixed infection in samples collected from Arizona and Colorado, two genotypes (EU and CH2) in Texas, and a single genotype (EU) in Alabama and California and the provinces of British Columbia and Ontario in Canada. The complexity of population genetics of PepMV in the United States poses an additional challenge to the greenhouse tomato industry because a tomato cultivar with durable resistance to multiple genotypes of PepMV may be harder to develop.
在短短几年内，番木瓜斑驳病毒病已迅速在全球温室番茄中成为地方病。尽管在美国已鉴定出三种番木瓜斑驳病毒（PepMV）基因型，但北美温室番茄作物中PepMV的遗传组成尚未确定。在本研究中，通过对来自31个田间采集样本的91个cDNA克隆的两个基因组区域（解旋酶结构域和TGB2-3）进行核苷酸序列比较和系统发育分析，评估了PepMV的遗传变异性和群体结构。这些样本取自美国五个州和加拿大两个省的几个主要温室番茄种植设施。在北美发现了PepMV的所有四种主要基因型（EU、US1、US2和CH2）。在从亚利桑那州和科罗拉多州采集的样本中发现三种不同基因型（EU、US1和US2）混合感染，在德克萨斯州发现两种基因型（EU和CH2），在阿拉巴马州、加利福尼亚州以及加拿大的不列颠哥伦比亚省和安大略省发现单一基因型（EU）。美国PepMV群体遗传学的复杂性给温室番茄产业带来了额外挑战，因为培育对多种PepMV基因型具有持久抗性的番茄品种可能更加困难。
