Análise Da Relação Entre Incidência E Severidade Foliar Da Cercosporiose Da Beterraba

Abstract

The occurrence of Cercospora leaf spot in beet can reduce the productivity and compromise the quality. The objective was to evaluate the relation between incidence and severity intensity of Cercospora leaf spot in beet. The experiment was conducted with the cultivar Boro in Catarinense Federal Institute/Campus Rio do Sul. The design was a randomized block design with four replications and six treatments made of fungicide, as the forecasting system proposed by Marcuzzo et al. with estimated severity (ES) accumulated of 0,15; 0,25, and 0,35 compared to application every 5 and 7 days in order to promote a disease gradient intensity in the years 2018 and 2019. The intensity of the disease was evaluated weekly using the severity and incidence. The data were submitted to linear regression analysis. Using the equation with the best fit in two seasons and replacing the severity value of 1% is obtained incidence of 4.8%. The estimated severity based on the incidence and the opposite enable its adequate use for technical assistance in the monitoring of Cercospora leaf spot in beet.