Effect of Center-Pivot Irrigation in the Rust and Brown Eye Spot of Coffee.

Incidence of rust (caused by Hemileia vastatrix) and brown eye spot (caused by Cercospora coffeicola) of coffee was evaluated for 2 years in southern Minas Gerais, Brazil, in a center-pivot-irrigated coffee crop with different water application levels. Treatments consisted of six water levels of 0 (nonirrigated), 60, 80, 100, 120, and 140% applied according to class A evaporation pan (CAE). Progress of disease was influenced significantly by different water levels; the highest incidence of rust occurred with lower water levels-0 (nonirrigated), 60, and 80% CAE-whereas the lowest incidence was detected with larger water levels: 120 and 140% CAE. There was one peak of rust incidence in August. The highest incidence of brown eye spot occurred with water levels of 100 and 140% CAE and the lowest incidence was found in the nonirrigated treatment. Two incidence peaks occurred in March and June. This study identified that irrigation methods and water levels can decisively affect the epidemiological behavior of diseases and, therefore, their management.