Seven isolates of Cercospora coffeicola, the etiological agent of brown eye spot in coffee, were studied in relation to micelial growth at different temperatures, sequences of the ITS1 and ITS2 ribossomic DNA regions and of part of the calmodulin gene, and pathogenicity to seedlings of eight coffee cultivars (Catuaí Vermelho IAC 81, Catuaí S H3, Tupi IAC 1669 - 33, Tupi RN IAC 1669 - 13, Icatu Vermelho IAC 4045, Ouro Verde IAC H 5010-5, Geisha IAC 1137 and Mundo Novo IAC 376-4). The temperatures that promoted the highest micelial growth varied among isolates: 23,8, 23,7 and 23,9ºC for isolates IBLF277, IBLF280 and IBLF379; 24,6ºC to 25,1ºC for isolates IBL199 and IBLF270; and 27,6 and 27,8ºC for isolates IBLF004 and IBLF206. In the phylogenetic analysis, isolates IBLF270 and IBLF379 were separated in a subgroup, but the sequences of part of the calmodulin gene of all isolates showed 100% identity. The most pathogenic isolates for all coffee cultivars were IBLF277, IBLF270, IBLF379 and IBLF199. The cultivar Ouro Verde IAC H 5010-5 was the most resistant to brown eye spot and the cultivars Geisha IAC 1137, Mundo Novo IAC 376-4 and Tupi IAC 1669-33 were the most susceptible, but in the second experiment there was interaction between cultivars and isolates.
Coffea arabica; cercosporiosis; brown eye spot; resistance; genetic variability
