Avaliação de diferentes estratégias de fungicidas no controle da mancha de Bipolaris no milho e seus efeitos na produtividade de grãos

Bipolar leaf spot, caused by the fungus Bipolaris maydis, has become one of the main foliar diseases affecting corn crops, especially in regions with warm and humid climates. This disease affects the active leaf area of the plant, interfering with photosynthesis and, consequently, productivity. Therefore, this study aimed to evaluate the effectiveness of different fungicide application strategies to control the disease and their effects on grain yield of the DKB 356 hybrid. The experiment was carried out at the IFMG – Bambuí Campus, using a randomized block design with five treatments, varying the number of applications and the products used. Visual assessments of leaf spot severity were made on standard leaves, and at the end of the cycle, a harvest and productivity analysis was performed. The data were subjected to statistical analysis using ANOVA and the Scott-Knott test at a 5% probability level. Treatments that received fungicide applications showed lower disease severity and higher grain yield. Treatment 4 showed the best yield, followed by treatments 3 and 5. It is noteworthy that treatment 3, even without fungicides, showed similar results to those of the chemical treatments, indicating a possible secondary action of the insecticide used or the influence of environmental conditions. The results show that well-planned chemical management can significantly contribute to controlling leaf spot caused by Bipolaris and increasing productivity. Furthermore, they reinforce the importance of integrated strategies that reconcile agronomic efficiency with sustainability.