Antagonistic and molecular characterization of endophytic Trichoderma from sugarcane

Abstract

The genus Trichoderma is used worldwide to control fungal diseases and promote the growth of plants. It is the subject of many studies and forms part of most commercial formulations with biological control agents. In Brazil, it is used in approximately 78 registered commercial products. This work aims to isolate and evaluate the in vitro antagonism of Trichoderma endophytes from sugarcane, through pairing cultures and bioassays of the production of volatile and non-volatile metabolites, in addition to carrying out its molecular identification based on partial sequencing of molecular markers. In the paired culture assay against Fusarium verticillioides, Phaeocytostroma sacchari, Thielaviopsis sp. and Colletotrichum falcatum, mycelial growth inhibition rates were above 76.27%. In tests evaluating the production of volatile and non-volatile metabolites, the isolates promoted inhibitions that varied between 0 and 50.19% and 0 and 35.69%, respectively. According to the molecular phylogeny carried out, the concatenated analysis of the genetic markers revealed that the seven isolates belong to the species Trichoderma afroharzianum and, given the great potential as antagonists observed for sugarcane pathogens, they will be evaluated through in vivo disease control trials and tested for the growth promotion of this plant.