ABSTRACT
Carrot cultivation has intensified due to in natura consumption and industrial canning processing. However, carrot leaf spot (Alternaria dauci) has compromised the productivity. As the epidemiological behavior of this disease in southern Brazil is not known, the present study aimed to analyze its temporal epidemiology in different carrot genotypes. In an experimental design of randomized blocks and four replicates, the following genotypes were evaluated: “Alvorada calibrada média”; “Brasília”; “Brazlândia”; “Ferracini”; “Flakee”; “Nantes”; “Nantes Express” and “Suprema calibrada média”. To evaluate the disease severity, a diagrammatic scale was used for ten plants previously demarcated at random. The disease progress curve for each genotype was adjusted to Gompertz model, since the observed severity corresponded to the model and was confirmed by the consistency between estimated points and the residue. The genotype “Suprema” showed the highest progress rate (0.533), while “Brazlândia” (0.368) showed the lowest rate. “Nantes” had the highest severity peak, 66.9%, and “Suprema” had the lowest disease accumulation, 48.2%. The genotypes had no differences in their behaviors for temporal progress of carrot leaf spot.
Keywords
Daucus carota; genotypes; epidemiology; Alternaria dauci
