Utilizing Trichoderma spp. as an alternative for the promotion of plant growth and the control of anthracnose in avocado crops

Abstract

Avocado is a major crop of economic interest in the Montes de María region, known for its significant nutritional benefits. In recent years, avocado cultivation in Montes de María has been affected by the fungus Colletotrichum gloeosporioides, which causes substantial crop losses. To control this pathogen, agrochemical applications are typically required, but these can disrupt the soil microbiota. As an alternative, Trichoderma spp. is a fungus capable of controlling pathogens through the production of metabolites and also stimulates plant growth. The objective of this study was to evaluate the in vitro antifungal activity of native strains of Trichoderma spp. against C. gloeosporioides and their growth-promoting effects on avocado plants. Seven strains of Trichoderma spp. were molecularly identified as Trichoderma harzianum, T. viride, T. reesei, T. atroviride, T. longibrachiatum, T. peberdyi, and T. koningiopsis. These strains showed significant statistical differences in in vitro antagonism tests against C. gloeosporioides. Additionally, they demonstrated statistically significant (p<0.05) growth-promoting effects, with T. harzianum and T. viride being the most effective at enhancing plant height, stem diameter, and fresh root weight compared to commercial Trichoderma. Trichoderma harzianum and T. viride exhibited inhibitory activity against C. gloeosporioides in vitro and increased the biomass of avocado plants, making them a viable alternative for the integrated management of anthracnose in avocado plantations in the Montes de María.