Programas de aplicação de fungicidas para o controle de Oídio em trigo

Abstract

Powdery mildew is one of the most important diseases in the culture of wheat, since it can appear in the early stages of plant development. To avoid more significant losses in the crop, it is necessary to have a correct selection of fungicides used as well as the positioning of each one. Thus, to evaluate programs for fungicide application in wheat, with a view to a more assertive management in the control of powdery mildew and its effects on productivity of the crop. The experiment was conducted in the Experimental Area of UFFS - Erechim Campus in the 2021 crop season, with entirely randomized design (IDC) with 4 replicates and 5 treatments, totaling 20 experimental units. Treatment T1 represented the control, in which no fungicides were applied, and the other treatments (T2, T3, T4 and T5) received fungicides according to the application programs (aplic. ): T2: fenpropimortfe; picoxystrobin; cyproconazole; trifloxystrobin; metconazole; pyraclostrobin; azoxystrobin; T3: tetraconazole; azoxystrobin; picoxystrobin; cyproconazole; trifloxystrobin; metconazole; pyraclostrobin; tebuconazole; T4: tetraconazole; azoxystrobin; kresoxim-methyl; epoxiconazole; pyraclostrobin; metconazole; thiophanate-methyl; tebuconazole; T5: tetraconazole; azoxystrobin; tebuconazole; chlorothalonil; thiophanate-methyl; epoxiconazole; pyraclostrobin. Mildew incidence and severity, and grain yield were quantified. For the incidence and severity of powdery mildew, the results showed a significant difference among the treatments evaluated. All treatments that received fungicide application obtained a higher productivity when compared to the control, with T4 presenting a productivity 14% higher than the control, statistically different from the others. The treatments T4 and T5 obtained better efficiency in powdery mildew control. It can be concluded that the application program performed in T4 provides efficiency in the control of powdery mildew, as well as greater productivity for the wheat variety TBIO Astro.