PROGRESSO E ARRANJO ESPACIAL DO MOSAICO DOURADO EM FAVA

Abstract

The Golden mosaic, caused by Bean golden mosaic virus (BGMV), causes severe losses to faba beans (Phaseolus lunatus L.) growers in the Northeastern region of Brazil. This study aimed at analyzing the temporal and spatial aspects of the disease at two experimental plots (A and B with 1360 m2 each) cultivated with faba beans located in Rio Largo, Alagoas. The evaluation of the disease incidence was done by visual in-spection of all plants at 30, 60, 90, 120 and 150 days after planting (DAP). The epidemics were compared with respect to initial incidence (yo), maximum incidence (ymax), rate of disease progression (RDP), and area under the disease progress curve (AUDPC). The spatial pattern of the disease was analyzed by isopath mapping, ordi-nary runs, fitting the beta-binomial distribution and spatial autocorrelation. The analysis of the progress curves showed that the epidemic was significantly (P≤0.05) faster in plot B, probably associated with increased expo-sure to whitefly populations from areas external to assay. The within rows aggregation increased along with the period after planting and the increase in the disease incidence in both areas. In plot A, there was a slight pre-dominance of aggregation within the rows while, in plot B, the across rows aggregation of sick plants was prevalent.