Trichoderma spp. en la propagación sostenible de Theobroma cacao L. bajo distintos sustratos

The use of Trichoderma spp. represents a sustainable alternative to improve the propagation of Theobroma cacao L. seedlings. This study evaluated the effect of selected Trichoderma spp. strains on the germination and initial growth of Nacional cacao under different substrates in nursery conditions. Four strains (T. harzianum strains 1 and 2, T. reesei, and T. viride), as well as a control, were applied to three substrate mixtures: forest soil + organic compost, forest soil + perlite, and forest soil + peat. Seed germination was high (100%) in all treatments. However, seedling survival significantly improved with the use of peat (>90%) compared to forest soil + compost (52.5%). In terms of growth, T. viride in perlite promoted greater fresh root weight (12.18 g) and dry root weight (6.91 g), as well as greater seedling height (38.31 cm). Similarly, T. viride in peat generated the highest shoot fresh biomass (16.05 g) and dry biomass (9.19 g). The results confirm that inoculation with Trichoderma spp., in combination with suitable substrates, enhances the initial growth of cacao seedlings, increasing their vigor and productive potential in sustainable agroecological systems. The appropriate selection of strain and substrate is key to improving efficiency and sustainability in cacao nurseries, contributing to high-performance agriculture with lower dependence on chemical inputs