Phylogenetic Affinity in the Potential Antagonism of Trichoderma spp. against Moniliophthora roreri

Abstract

Frosty pod rot, caused by the fungus Moniliophthora roreri, is one of the most important diseases of cacao in Peru. Sustainable alternatives to control it include timely cultural practices such as pruning, and the application of biological control agents such as Trichoderma spp. We isolated 234 Trichoderma strains native to the department of Amazonas in Northern Peru from soil samples in cacao farms. These strains belong to at least eighteen species within four phylogenetic clades in the genus (Harzianum, Longibrachiatum, Hamatum, and Brevicompactum clades). We aimed to assess the in vitro biocontrol potential of these strains against M. roreri. We evaluated their mycoparasitism, antibiosis, and potential antagonism to select candidate strains for efficient biocontrol of M. roreri. We found evidence (Kruskal–Wallis test, p < 0.005) that strains belonging to the Harzianum clade tend to have higher mycoparasitism, antibiosis, and potential antagonism levels than strains in the Longibrachiatum and Hamatum clades. Additionally, this study constitutes the first report for antagonistic behavior against M. roreri for T. parareesei, T. lentiforme, T. orientale, T. asperelloides, T. inhamatum, T. zelobreve, T. afarasin, T. ghanense, T. rifaii, and T. breve. These results will be foundational for further M. roreri biocontrol studies.

Application of microencapsulated Trichoderma spp. against Moniliophthora roreri during the vegetative development of cocoa

“…Trichoderma asperellum extract was developed microcapsules using 20 ml, which consisted of a mixture with 80 ml of 2% sodium alginate previously sterilized, left stirring for 15 min, and sprinkled on a container that contained 2% Calcium Chloride (CaCl2), forming the microcapsules instantly (Lopes et al, 2020). The Trichoderma genus has been qualified as a biological control agent for diseases such as M. roreri and M. perniciosa, both under in vitro and in vivo conditions in several geographical locations (Mejía et al, 2008;Leiva et al, 2022). Trichoderma spp., presents great antagonistic potential on mycelial growth when competing for space with the phytopathogenic fungus (Suárez Meza et al, 2008).…”