Asiatic citrus canker (ACC, caused by Xanthomonas citri subsp. citri, [XccXcc]) is a serious disease of citrus, reducing yield and impacting marketability of fresh fruit. ACC has phytosanitary implications for fresh fruit trade. Lesions on fruit, leaves, and shoots in an orchard of ACC-susceptible grapefruit was monitored for production of Xcc from June to the following January in 2009 and 2010. Lesions on fruit post-harvest either packingline-treated or not treated were also monitored for production of Xcc on fruit harvested in November 2013 and January 2014. Shoot lesions generally produced fewer bacteria and had a smaller proportion of active lesions compared to leaf and fruit lesions. As the season progressed the proportion of active lesions on fruit and shoots gradually declined. Bacterial flux density (BFD) in surviving lesions was >10³ on all organs at all sample times. A window-pane analysis revealed weather variables associated with bacterial survival within the lesion. The packingline treatment had no effect in reducing the proportion of active lesions, and had only a small, transient effect reducing BFD (∼1.5 log units). Lesion size affected survival – small lesions (<10 mm²) declined in activity rapidly compared to larger lesions, both in the field pre-harvest, and post-harvest in storage. Although lesions of ACC on fruit, leaves, and shoots are a constant source of inoculum, steps that can be taken to minimize early infection of fruit which often results in large lesions will reduce the risk of inoculum dispersal. Current packingline treatments do not reduce activity of lesions of ACC. Based on these and other previously reported results, lesions on fruit post-harvest can be deemed a limited risk for spread of canker.

中文翻译：

---

亚洲柑橘溃疡病病原体 Xanthomonas axonopodis pv 的季节性和收获后种群动态。佛罗里达州柚子上的柑橘

亚洲柑橘溃疡病（ACC，由 Xanthomonas citri subsp. citri，[XccXcc] 引起）是一种严重的柑橘病害，会降低产量并影响新鲜水果的适销性。ACC 对新鲜水果贸易具有植物检疫意义。2009 年和 2010 年 6 月至次年 1 月监测了 ACC 易感葡萄柚果园中果实、叶子和枝条上的 Xcc 生产。在 2013 年 11 月和 2014 年 1 月收获的果实上产生 Xcc。与叶和果实病斑相比，茎部病斑通常产生较少的细菌，活动病斑的比例较小。随着季节的进行，果实和枝条上活跃病斑的比例逐渐下降。存活病灶中的细菌通量密度 (BFD) > 在所有采样时间在所有器官上为 10³。窗玻璃分析揭示了与病灶内细菌存活相关的天气变量。填充线处理对减少活动病灶的比例没有影响，并且只有很小的、短暂的降低 BFD 的效果（~1.5 log 单位）。病灶大小影响存活——与大病灶相比，小病灶 (<10 mm²) 的活动迅速下降，无论是在田间收获前还是在收获后储存。虽然果实、叶子和枝条上的 ACC 病斑是接种物的恒定来源，但可以采取措施尽量减少水果的早期感染，这通常会导致大病斑，从而降低接种物传播的风险。当前的包装线治疗不会降低 ACC 病变的活动。基于这些和其他先前报告的结果，