Endophytic fungal hitch-hikers have been difficult to detect in the past, and have potentially spread these latent pathogens via the global plant trade. The African genera Protea, Leucospermum and Leucadendron, commercially referred to as proteas, form the basis of a global flower production industry. The largest producers of proteas are Australia and South Africa, followed by Portugal and Spain. In the 1990s propagation material from South Africa was used to establish protea orchards in Portugal. We utilized metabarcoding to determine if this plant trade has carried host-specific fungal pathogens to a new environment. Wood samples collected from asymtomatic twigs from Portuguese farms, where propagation material had been imported from South Africa, was compared to material from South African farms that originally produced and supplied rooted and unrooted cuttings. DNA metabarcoding, using fungal-specific primers for the ITS2 gene region, produced 1237 OTUs. Focusing only on known pathogens of protea, we found that the Portuguese orchards contained fungal disease agents associated with Proteaceae or other plant families from the Southern Hemisphere. Our sampling technique could be used by agencies and applied to other plant material and pathogens to reduce the spread of pathogens.

过去很难发现内生真菌的搭便车者，并且潜在地通过全球植物贸易传播了这些潜在的病原体。非洲属普罗蒂亚，风轮花和千层，被称为普罗蒂亚茶，构成了全球花卉生产行业的基础。蛋白酶的最大生产国是澳大利亚和南非，其次是葡萄牙和西班牙。在1990年代，来自南非的繁殖材料被用于在葡萄牙建立普罗蒂亚果园。我们利用元条形码来确定这种植物贸易是否已将宿主特异性真菌病原体带入了新环境。从葡萄牙农场（从南非进口繁殖材料）的无症状小枝上收集的木材样品与最初生产并提供有根和无根插条的南非农场的材料进行了比较。使用针对ITS2基因区域的真菌特异性引物进行的DNA metabarcoding产生了1237个OTU。仅关注蛋白酶的已知病原体，我们发现葡萄牙果园中含有与Proteaceae或来自南半球的其他植物科相关的真菌病原体。我们的采样技术可以被机构使用，并应用于其他植物材料和病原体，以减少病原体的传播。