The Efficacy of Bordeaux Mixture and Trichoderma Powder in Preventing Fungal Diseases on Cashew Nut Wounds after Pruning

Cashew cultivation is an important agricultural industry in Cambodia, providing high income for farmers. Pruning cashew trees helps maintain their health and ensures adequate light exposure, but it also makes them susceptible to fungal infections, which can lead to reduced yields and cause some farmers to abandon cultivation. This study aimed to identify effective biological products for protecting cashew wounds from fungal infections. It was conducted in two phases: the first phase determined the inhibitory effects of Trichoderma asperellum on pathogenic fungi grown on potato dextrose agar plates, after which T. asperellum was produced in powder form. The second phase applied Bordeaux mixture and Trichoderma powder to cashew wounds, using a completely randomized design with three treatments: T1: 10% Bordeaux mixture, T2: 40% Trichoderma powder, and T3: 50% Trichoderma powder. Results showed that T. asperellum completely inhibited Rhizopus fungus within 6 days. One-way ANOVA analysis of the percentage of healing showed a significant difference (p < 0.01). T3 (50% Trichoderma powder) was the most effective, preventing fungal infection for up to 60 days and reducing the healing period from 90 to 3.83 ± 4.4%. The use of Trichoderma powder also protected against fungal diseases like gummosis, Penicillium, and Rhizopus, with 50% Trichoderma powder proving most effective in preventing fungal infections and speeding up wound healing after pruning.