Spatial distribution of citrus leprosis in the Eastern Amazon

ABSTRACT This study aimed to evaluate the spatial distribution of citrus leprosis in two orchards in the Eastern state of Pará/ Eastern Amazon citrus region. Two evaluations were performed at monthly intervals between December, 2011 and November, 2012 checking plants with characteristic symptoms of citrus leprosis by recording 1 for presence and 0 for absence. To analyze the disease spatial distribution in the plots, geostatistics was used for semivariogram modeling, and elaboration of kriging maps. The model that better adjusted to the disease spatial distribution was the spherical, the one with the highest coefficient of determination with variations ranging from 18 to 19 meters in area A and 9 to 30 m in area B. The Spatial Dependence Index (SDI) was moderate for all area A evaluations with interval ranging from 0.25 to 0.75, while in area B, except for the months of December 2011, June and September 2012 with a moderate SDI, all the others showed a weak SDI with values below 0.25. Geostatistical analysis has shown itself to be an ideal tool to evaluate Citrus leprosis virus (CiLV) spatial distribution.