Antagonismo de Trichoderma spp. sobre Mycosphaerella fijiensisMorelet, Agente Causal de la Sigatoka Negra del Plátano (Musasp.) in vitro e Invernadero

The antagonistic effect of strains of Trichoderma spp. against Mycosphaerella fijiensis was evaluated in vitro and in the greenhouse. Twenty five native strains of the antagonistic fungus were isolated, and eight of those (J20, J25, J24, J1, J7, J12, J11, and J9) were selected through the cellophane paper method. In dual cultures, the phytopathogen stopped its growth once in contact with the strain of the antagonistic. Out of the eight selected strains, six were classified in type 1 of antagonism: Trichoderma spp. overgrew the pathogen covering 100% of the medium culture, while 2 strains (J1 and J9) showed antagonism type 3, where none of the two fungi were dominant; there were no strains classified in types 4 and 5. In the greenhouse, strains J7 and J11 showed the smallest pondered percentages of infection with 0.70 and 0.88%, respectively, on development of M. fijiensis, with a consequently better disease control; therefore, it is suggested to evaluate these strains under field conditions.