Bioprospection of Trichoderma spp. originating from a Cerrado-Caatinga ecotone on Colletotrichum truncatum, in soybean

Abstract

This study aimed to assess the potential of 19 isolates of Trichoderma spp. originating from a Cerrado-Caatinga ecotone in control of Colletotrichum truncatum, in soybean. In vitro tests (inhibitory effect of volatile and fixed thermostable metabolites) were carried out to assess the percentage of mycelial growth of the pathogen and in vivo tests (in soybean seeds) were performed to assess the percentage of germination, germination rate index, dry matter, and health of seeds. Regarding the pathogen growth under the effect of volatile and fixed thermostable metabolites, the lowest values were provided, respectively, by the isolates UFPIT03 (49.25%) and UFPIT13 (38.38%). No significant differences were observed in the in vivo tests regarding the action of volatile metabolites of the different isolates. In relation to the effect of fixed metabolites, the isolates UFPIT11 and UFPIT19 presented the best results, with the highest means of seed dry matter and lower pathogen incidence. However, the other isolates also showed positive results. It is noteworthy that this is the first report of Trichoderma orientale in the biocontrol of a plant pathogen. Thus, the perspectives of using these species of Trichoderma originating from native forest fragments in the biological control of phytopathogens are evidenced.