ABSTRACT
Target spot, caused by the fungus Corynespora cassiicola, occurs endemically in Amazonas State, leading to reduced production in several crops. This study evaluated the pathogenicity of C. cassiicola isolates in tomato, eggplant and papaya. Isolates were obtained from crop areas in the cities of Manaus, Iranduba and Presidente Figueiredo in Amazonas State. The disease severity was assessed, as well as the number and the diameter of lesions. Experimental design was completely randomized in a factorial arrangement of 9x3x3 (9 isolates, 3 areas and 3 hosts) and 3 replicates. Papaya isolates caused symptoms in all evaluated plant species, and a certain degree of specificity was demonstrated for eggplant and tomato isolates, which did not cause disease in papaya. Severity was higher in tomato plants. The isolates obtained from Iranduba were most aggressive, suggesting that the geographic origin influenced the aggressiveness of isolates.
Keywords
target spot; cross pathogenicity; specificity