Comparison of the Efficacy of Trichoderma and Bacillus Strains and Commercial Biocontrol Products against Grapevine Botryosphaeria Dieback Pathogens

Grapevine trunk diseases (GTDs) cause significant yield losses worldwide and limit the lifespan of vineyards. In last few years, using biological control agents (BCAs) for pruning wound protection has become a promising management strategy these pathologies. This study aimed to compare antifungal activities grapevine-native Trichoderma harzianum isolate high-potential Bacillus velezensis strain against two pathogenic Botryosphaeriaceae species in artificially inoculated, potted, grafted plants under controlled greenhouse conditions, taking three commercial biocontrol products (based on T. atroviride I-1237, T-22, subtilis BS03 strains) as reference. To reproduce certain field conditions more realistically, inoculation protective pathogens was conducted simultaneously immediately after instead allowing BCAs colonize wounds before pathogen inoculation. Significant differences necrosis lengths were detected both Neofusicoccum parvum- Diplodia seriata-infected plants, remarkable effect BUZ-14 observed all cases. Trichoderma-based treatments showed different efficacies fungi. While tested resulted reductions vascular caused by N. parvum, they did not significantly reduce D. seriata infection compared untreated inoculated control. The B. effective. reported results provide support potential may have fungi, encouraging its evaluation natural conditions.