Abstract

Citrus black spot caused by Phyllosticta citricarpa Van der Aa is a quarantine pest that causes premature fruit drop, restricts exports, and results in significant losses in Brazilian citrus farming production, where its occurrence must be monitored. This study aimed to analyze the spatio-temporal dynamics and seasonal patterns of prevalence and incidence of citrus black spot in Eldorado do Carajás, Pará, Brazilian Eastern Amazon. A total of 181 properties were inspected, showing prevalence rates of 5.6, 4 and 7.8%, and annual average incidence rates of 62, 73, and 61% in 2019, 2021 and 2022, respectively. A total of 439 diseased plants were eradicated across 11 foci, with higher incidence in the drier period (81.8%) compared to the wetter period (18.2%). This was influenced by relative humidity, minimum temperature, and rainfall. The incidence was diagnosed in 90% of domestic plantings and 10% of commercial production units. The citrus species with the highest incidence were sweet orange (52.9%), tangerine (29.4%) and rangpur lime (17.6%) in orchards over 10 years old. At the property level, incidences showed an aggregated spatial pattern explained by the Gaussian model and autocorrelation via Moran's Index, with disease spread ranging from 25.5 to 103 m. At the municipal level, the foci were spatially random. Mapping revealed that rural properties with foci were easily accessible for the sale of contaminated seedlings, posing a threat to the competitiveness of citrus fruit marketing and the sustainable development of Amazonian citrus farming.