Trichoderma juruarense sp. nov. (Hypocreaceae) a new fungal species from sediments of the Amazonian Juruá River with agricultural potential
Abstract The species of Trichoderma are the most common fungi to be used as biocontrol agents, and their metabolic arsenal has a wide variety of applications that places this genus among those with the potential to provide biotechnological products. The ubiquitous nature of Trichoderma has favored a rapid increase in the number of described species, and significant efforts have been made towards the taxonomy of Trichoderma in order to improve the accuracy of identification. During a study of cultivable microbiota from the Juruá River, Amazon, Brazil. Isolates with morphological characteristics of the genus Trichoderma were screened for their capacity to control phytopathogens. A total of five Trichoderma isolates were identified using morphological data combined with phylogenetic analysis of the ITS region, and partial sequences of TEF and RPB2. Trichoderma juruarense sp. nov. form a monophyletic clade that is closely related to T. cyanodichotomus, a species that occupies an unresolved position in the Trichoderma taxonomy. T. cyanodichotomus and T. juruarense sp. nov. present an intracellular blue-green pigment in potato dextrose agar (PDA) and differ in conidia and chlamydospores sizes. These data support the proposition of a new species, named here as Trichoderma juruarense. The holotype of T. juruarense INPA0108 presents in vitro inhibition against phytopathogens, such as Colletotrichum siamense (50%), Corynespora cassiicola (43%), Fusarium decemcellulare (61%) and Sclerotium rolfsii (51%), which demonstrates desirable traits that warrant further studies on plant protection. In addition, T. cyanodichotomus and T. juruarense formed a new clade based on the sequence data of the RPB2 gene.