Eficiência de isolados de Trichoderma spp. no controle biológico in vitro de Ceratocystis fimbriata

Abstract

Eucalyptus cultivation is of great importance to the Brazilian forestry sector, representing the main planted species in the country due to its high productivity. However, diseases caused by phytopathogens, such as wilt induced by Ceratocystis fimbriata, have caused significant losses to the forestry sector by reducing tree volume growth and industrial wood yield. Given the ineffectiveness of conventional chemical methods and their associated environmental impacts, biological control emerges as a sustainable and promising alternative. This study aimed to evaluate, through in vitro tests, the antagonistic potential of Trichoderma spp. isolates against C. fimbriata. Twenty Trichoderma spp. isolates were used in dual culture assays and conidial germination tests. The isolates were evaluated for their ability to inhibit pathogen growth and reduce germ tube elongation. Six isolates were selected for the second stage of testing, with isolate T09 standing out by significantly reducing the germ tube length of C. fimbriata, with an average of 17.88 µm compared to the control's 70.66 µm. Data were subjected to statistical analysis, with significant differences between treatments confirmed by ANOVA and Tukey's test. The results demonstrate that Trichoderma spp. isolates have promising potential as biocontrol agents against Ceratocystis wilt. However, further studies under non- controlled conditions are necessary to assess the practical application feasibility of these isolates, considering plant response variability and interactions with the pathogen.