Susceptibility of eight banana cultivars to sigatoka caused by Mycosphaerella musicola was assessed in a field experiment in the region of Marília, State of São Paulo. Three cultivars were members of AAA Group ('Nanicão', 'Nanicão Jangada' and 'Grande Naine') and five belonged to AAB Group ('Prata', 'Enxerto', 'Maçã', 'Mysore' and 'Prata Zulu'). The experiment was established in February, 1992, and during the first three years, sigatoka disease was not controlled. Susceptibility was assessed in three occasions: March, 1993, April and July, 1994. In the first, it was counted the number of spots on the second leaf, and in the others, the plants were graded according to the amount of leaf scorch due to sigatoka. The cultivars were classified in three classes according to the degree of susceptibility: highly susceptible (HS), susceptible (S) or partially resistant (PR). None of the cultivars could be considered highly resistant or immune because all of them showed some symptoms. Outstanding as the most susceptible, there were the AAA Group (Cavendish subgroup) cultivars ('Nanicão', 'Grande Naine' and 'Nanicão Jangada') and 'Enxerto' (AAB). 'Mysore' (AAB) and 'Prata Zulu' (AAB) were classified as partially resistant, while 'Prata' (AAB) and 'Maçã' (AAB) showed moderate susceptibility.
disease resistance; Musa sp.; Mycosphaerella musicola Leach; Cercospora musae Zimm