Invasive plant pathogens cause a substantial loss of yearly revenue and often lead to environmental change. The movement of plants is considered to be the main avenue for introduction of invasive plant pathogens. Government agencies attempt to reduce the risk of introductions by legislation and inspections. However, inspectors may not consider that plant pathogens can infect plants as endophytes that are not considered hosts without showing symptoms. This study surveyed endophytes in rhododendron (Rhododendron maximum and Rhododendron catawbiense) plants in four native stands in the Eastern U.S.A. We isolated associated endophytes from the plant leaves and identified them using a molecular sequencing method. Fifteen (21%) of the identified samples matched with a known plant pathogen not reported to be pathogenic on rhododendron. We demonstrated pathogenicity of selected rhododendron endophytes on red oak, flowering dogwood and lupine. This study is important because it highlights that present detection methods and techniques may not be adequate to detect the potential importation and spread of invasive species.

入侵性植物病原体导致每年收入的大量损失，并经常导致环境变化。植物的运动被认为是引入入侵性植物病原体的主要途径。政府机构试图通过立法和检查来减少引入的风险。但是，检查人员可能不会认为植物病原体可以作为植物的内生菌感染植物，而这些植物不会被视为宿主而不会表现出症状。这项研究调查了杜鹃（Rhododendron maximum和Rhododendron catawbiense）中的内生菌。美国东部四个原生林中的植物我们从植物叶片中分离出相关的内生菌，并使用分子测序方法对其进行了鉴定。鉴定出的样品中有十五个（21％）与已知的植物病原体相匹配，该病原体据报道对杜鹃花没有致病性。我们证明了选定的杜鹃花内生菌对红橡树，开花的山茱and和羽扇豆的致病性。这项研究很重要，因为它突显了当前的检测方法和技术可能不足以检测入侵物种的潜在进口和扩散。