Abstract

Abstract: The effectiveness of two Trichoderma spp. formulations in the control of Cylindrocarpon macrodidymum affecting table grapes cropped under a semi arid climate conditions (3th Region of Chile in Copiapó), was evaluated through trials conducted during two seasons. The orchards were selected according C. macrodydimum damage (low growing ratio and yield of the plants). Treatments were run applying Trichoderma spp. into the soil as: a solid formulation, sodium alginate pellets including either a wild or an improved strain, and a liquid formulation of a commercial Trichoderma spp. biofungicide. An absolute control was also set. The experimental design was a complete randomized block. Results were analyzed by ANOVA and Tukey`s test. C. macrodidymum populations, before and after treatments were compared to controls, as well as percent of yield increase and yield per plant. Survival of Trichoderma spp. in the soil of both formulations was also evaluated. Results showed that no statistical differences were observed in the C. macrodidymum populations after Trichoderma spp. treatments independently of the type of formulation. However, percent of yield increase was statistically significantly higher than control, when Trichoderma spp. formulations were applied. The Trichoderma populations in the soil after treatment with the solid formulations was higher than the one obtained with the liquid biofungicide. The results indicate that soil treatments with Trichoderma spp. in table grapes affected by C. macrodidymum resulted in a yield increase in treated plants cropped in a semi arid region of Chile.