Antagonism of Trichoderma strains isolated from Tanaxuri, Michoacan, Mexico against postharvest pathogens of avocado fruits (Persea americana Mill)

Some species of the genus Trichoderma have the abil-ity to parasitize fungal plant pathogens. This characteristic provides a high potential for use in the control of diseases (anthracnose) caused by fungi in post-harvest avocado fruit. Therefore, the objective of this research was the isolation and identification of native Trichoderma strains from avocado cul-tures with antagonistic potential in vivo and in vitro against pathogens of this fruit. The strains were isolated from the root and soil of the avocado in the town of Tanaxuri, Micho-acan. Six strains were obtained and characterized as TSONM1 (Trichoderma spp.), TRONM2 (Trichoderma spp.), TSONM3 (Trichoderma spp.), TSONM4 (Trichoderma spp.), TSONM5 (Trichoderma spp.) and TSONM6 (Trichoderma harzianum). Subsequently, the isolated strains were confronted with Neo-fusicoccum parvum, Colletotrichum gloeosporioides, Diaport-he sp. and Phomopsis perseae, observing in vitro inhibitions greater than 80 %. In the in vivo evaluation, the TSONM6 strain (Trichoderma harzianum) showed greater antagonistic activity against C. gloeosporioides, Diaporthe sp. and P. persea. Additionally, the avocado fruits treated with TSONM6, pre-sented minimum percentages (< 2 %) of pulp and peduncle rotting. Therefore, Thichoderma harzianun could be a good alternative for postharvest biological control of avocado.