Department of Plant Pathology, Cornell University, Ithaca, NY, USA.
Phytopathology. 2010 Nov;100(11):1185-93. doi: 10.1094/PHYTO-01-10-0023.
Eastern North America is considered the center of diversity for many Vitis spp. and for the grape powdery mildew pathogen, Erysiphe necator. However, little is known about populations of E. necator from wild Vitis spp. We determined the phenotypic variation in pathogenicity and aggressiveness of E. necator among isolates from wild and domesticated Vitis spp. from diverse geographic regions in the eastern United States. To test pathogenicity, we inoculated 38 E. necator isolates on three wild Vitis spp., two commercially grown hybrids and the European wine grape, Vitis vinifera. V. rotundifolia (muscadine grape) was the only host species on which complete host specialization was evident; it was only susceptible to isolates collected from V. rotundifolia. All isolates, regardless of source host, were pathogenic on the other Vitis spp. We found no differences in components of aggressiveness latent period and lesion size among isolates from different source hosts when inoculated on V. vinifera, which is highly susceptible to powdery mildew. However significant variation was evident among isolates on the more resistant V. labruscana 'Niagara'. Isolates from the wild species V. aestivalis were the most aggressive, whereas isolates from V. vinifera were not more aggressive than isolates from other source hosts. Greater aggressiveness was also detected among isolates from the southeastern United States compared with isolates from the northeastern United States.
东亚是许多葡萄物种和葡萄白粉病病原菌（Erysiphe necator）多样性的中心。然而，对于来自野生葡萄物种的白粉病病原菌种群知之甚少。我们确定了来自美国东部不同地理区域的野生和栽培葡萄物种的白粉病病原菌 E. necator 分离株在致病性和侵袭性方面的表型变异。为了测试致病性，我们将 38 个白粉病病原菌分离株接种在三种野生葡萄物种、两种商业种植的杂种和欧洲酿酒葡萄 Vitis vinifera 上。V. rotundifolia（麝香葡萄）是唯一明显表现出完全宿主专化性的宿主物种；它只对从 V. rotundifolia 采集的分离株敏感。所有分离株，无论其来源宿主如何，均可在其他葡萄物种上致病。当接种在对白粉病高度敏感的 V. vinifera 上时，我们没有发现来源宿主不同的分离株在潜伏期和病斑大小等侵袭性成分方面有差异。然而，在更具抗性的 V. labruscana 'Niagara' 上，分离株之间存在显著差异。来自野生物种 V. aestivalis 的分离株最具侵袭性，而来自 V. vinifera 的分离株并不比来自其他来源宿主的分离株更具侵袭性。与来自美国东北部的分离株相比，来自美国东南部的分离株也表现出更高的侵袭性。
