Doses de fungicida multissítio no controle de mancha amarela em trigo

Abstract

Wheat is an important cereal in human nutrition, but the crop is subject to the incidence of diseases, such as yellow spot, which causes considerable losses in productivity. The objective of this work was to evaluate the efficiency of applying different doses of multisite fungicide, associated or not with systemic fungicides, to control yellow spot in wheat. The experiment was conducted in the Experimental Area of the UFFS - Erechim Campus, in the 2021 crop. The wheat cultivar TBIO Noble was used in a randomized block design (BCT) with 4 replications and 6 treatments, totaling 24 experimental units. The treatment T1 represented the control, in which no fungicide was applied, and the other treatments (T2, T3, T4, T5 and T6) received fungicide application according to the application programs: T2: fluxapyroxad; pyraclostrobin; epoxiconazole; trifloxystrobin; tebuconazole; methyl thiophanate; T3: fluxapyroxad; pyraclostrobin; mancozeb; epoxiconazole; trifloxystrobin; tebuconazole; methyl thiophanate; T4: fluxapyroxad; pyraclostrobin; mancozeb; epoxiconazole; trifloxystrobin; tebuconazole; methyl thiophanate; T5: fluxapyroxad; pyraclostrobin; mancozeb; epoxiconazole; trifloxystrobin; tebuconazole; methyl thiophanate; T6: fluxapyroxad; pyraclostrobin; mancozeb; epoxiconazole; trifloxystrobin; tebuconazole; methyl thiophanate. The incidence severity of yellow spot in wheat was evaluated, as well as grain yield. Application programs 5 and 6 showed the best percentages of yellow spot control in wheat. The best results for number of full grains, ear length and thousand grain weight were obtained in application programs 5 and 6. The highest yield was obtained with application schedule 6 resulting in a yield 19% higher than the control. It can be concluded that the application programs represented in T5 and T6 provide 95.90 and 100.00% efficiency in the control of yellow spot, thus presenting the best yield for the wheat cv.