Phyllosticta cavendishii has been recorded in the Northern Territory (NT) of Australia occurring on non‐Cavendish bananas since 1991. The race of P. cavendishii that infects Cavendish bananas is considered exotic to Australia and classified as an emergency plant pest. In July 2013, P. cavendishii was detected on Cavendish bananas near Darwin, NT. Here, the diagnoses and field observations carried out during the Incident Definition Phase of the national biosecurity response, from July 2013 to October 2014, are reported. Of 1395 banana samples collected from 676 properties, 480 were positive for freckle disease, including 463 samples with P. cavendishii and 17 samples with P. maculata. Phyllosticta cavendishii was detected in 256 properties, including 62 properties where it was detected on Cavendish banana plants, within six distinct geographical zones across the NT. Phyllosticta cavendishii was detected on two cultivars within the Cavendish subgroup and six non‐Cavendish cultivars. Multigene characterization of Phyllosticta cultures showed that P. cavendishii was isolated from both Cavendish and non‐Cavendish cultivars. Multilocus phylogeny analyses also revealed that the P. cavendishii strain in the outbreak had identical sequence similarity to the holotype (CBS H‐20918) clade 2 P. cavendishii isolates that infect both Cavendish and non‐Cavendish cultivars in Southeast Asia and Oceania. The genetic data in this study showed that there was one P. cavendishii strain infecting both Cavendish and non‐Cavendish cultivars in the outbreak. However, historical data and field observations provided anecdotal evidence for the existence of two races of P. cavendishii, including one that does not infect Cavendish bananas.

中文翻译：

---

澳大利亚卡文迪什香蕉雀斑病（Phyllosticta Cavendishii）的爆发和初步生物安全反应

自 1991 年以来，在澳大利亚北领地 (NT) 就记录了 Phyllosticta cavendishii 发生在非卡文迪什香蕉上。 感染卡文迪什香蕉的卡文迪什假单胞菌被认为是澳大利亚的外来植物，被归类为紧急植物害虫。2013 年 7 月，在北领地达尔文附近的卡文迪什香蕉上发现了卡文迪什假单胞菌。此处报告了在国家生物安全响应事件定义阶段（2013 年 7 月至 2014 年 10 月）期间进行的诊断和现场观察。在从 676 个物业收集的 1395 个香蕉样本中，480 个对雀斑病呈阳性，其中 463 个样本为卡文迪什假单胞菌，17 个样本为黄斑假单胞菌。在 256 处房产中检测到了 Phyllosticta Cavendishii，其中 62 处房产中检测到了卡文迪什香蕉植物，在整个北领地六个不同的地理区域内。在卡文迪什亚组中的两个品种和六个非卡文迪什品种中检测到 Phyllosticta Cavendishii。Phyllosticta 培养物的多基因特征表明，P.cabendishii 是从卡文迪什和非卡文迪什栽培品种中分离出来的。多位点系统发育分析还表明，暴发中的卡文迪什假单胞菌菌株与正型（CBS H-20918）进化枝 2 卡文迪什假单胞菌分离株具有相同的序列相似性，后者感染东南亚和大洋洲的卡文迪什和非卡文迪什栽培品种。本研究中的遗传数据表明，在暴发中，有一种卡文迪什假单胞菌菌株同时感染了卡文迪什和非卡文迪什栽培品种。然而，历史数据和实地观察为 P. 的两个种族的存在提供了轶事证据。