Coffee leaf rust in Brazil: historical events, current situation, and control measures

Abstract

In this review of coffee leaf rust (CLR) in Brazil, we report: (i) the historical introduction of CLR in Brazil and the first control measures; (ii) favorable environmental conditions and times of year for the disease; (iii) breeding methods and strategies used for developing CLR-resistant cultivars; (iv) the levels, sources, and types of CLR resistance; (v) the development of Brazilian resistant cultivars; and (vi) chemical and cultural control methods. Most plantations are cultivated with susceptible cultivars, such as those of the Catuaí and Mundo Novo groups. Brazilian research institutes have developed dozens of cultivars with different levels of resistance, and significantly increased the planting of new resistant cultivars. The main sources of CLR resistance are genotypes from Híbrido de Timor, Icatu, BA series carrying the SH3 gene, and Ethiopian wild coffees. High CLR resistance is still observed in Sarchimor and SH3-carrying genotypes. Intermediate CLR resistance is observed in Ethiopian wild coffees and in Sarchimor and Icatu derivatives, where qualitative resistance has been supplanted by races of Hemileia vastatrix. Contact, mesostemic, and systemic fungicides are used for chemical control in Brazil. CLR incidence in Brazil begins to increase after the rainy season onset in November, reaches a peak in June, and remains high until August. Thus, chemical control is typically applied from December to April.