Oat cultivars more efficient at reducing fungicide can prevent contamination of soil, water and food. The objective of the study is to measure the efficiency of oat cultivars recommended for growing in Brazil by reducing the number of fungicide applications, considering favorable and unfavorable crop season conditions for productivity and progress of the main leaf diseases. The study was conducted in 2015, 2016 and 2017, in Augusto Pestana, RS, Brazil. The experimental design was a randomized block with three replications in a 22 x 4 factorial scheme, for 22 oat cultivars and 4 conditions of fungicide use [without application; an application at 60 days after emergence; two applications at 60 and 75 days after emergence; and three applications at 60, 75 and 90 days after emergence]. The fungicide FOLICUR® CE was used in 2015 and 2016 and the fungicide PRIMO® in 2017 in the dosage of 0.75 and 0.3 liters ha-1, respectively. The plots were sprayed using BD 04 fan nozzle with 45 PSI pressure, and spray volume close to 120 liters ha-1. The condition of a crop season favorable to the progress of leaf diseases identifies with quality cultivars more efficient in reducing the use of fungicide, enabling processes with lower environmental impacts with food security. Under favorable agricultural year conditions and unfavorable to the productivity and progress of the main leaf diseases of oats, the most efficient cultivars to reduce the use of fungicide are URS Altiva and URS Guria

O estudo teve como objetivo comparar dois aparelhos portáteis (Optium Xceed® e Ketovet®) para o diagnóstico de cetose subclínica no campo; conhecer a prevalência desta patologia na região noroeste do estado do Rio Grande do Sul, em sistemas à pasto e confinado; avaliar a composição do leite de vacas em diferentes níveis de corpos cetônicos e glicose no sangue. Os dados foram coletados de três propriedades leiteiras do município de Augusto Pestana, Rio Grande do Sul, Brasil, sendo duas propriedades em sistema de manejo alimentar à pasto e uma em sistema de Compost Barn, sendo todos os bovinos da raça holandesa. Com a realização deste estudo conclui-se que a cetose apresenta prevalência maior, em sistema à pasto no período pós-parto devido à alta exigência de energia para a produção de leite dos animais; ambos os aparelhos Ketovet® e Optium® são eficazes no diagnóstico de cetose subclínica independente do período (pré ou pós-parto) e dos sistemas avaliados (à pasto ou confinado) e a ocorrência de cetose subclínica não causa alterações significativas na composição do leite de vacas. A cetose é um tema de extrema importância na bovinocultura de leite, sendo um assunto encontrado diariamente na rotina veterinária, revelando que é possível realizar o diagnóstico de forma rápida e com baixo custo à campo, possibilitando evitar perdas sanitárias e financeiras aos rebanhos.

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Purpose: The objective of the study is to analyze the management of the fungicide that seeks a longer interval between the last application and the harvest of oat grains, with an indication of the cultivars with the highest satisfactory productivity without application in the grain filling. Validate artificial neural network models in the expectation of satisfactory productivity with food security, through the interaction between management, pathogen, genotype, and environment.   Method/design/approach: The study was conducted in 2015, 2016, 2017, in a randomized block design, in a 22 x 4 factorial scheme, for 22 white oat cultivars (recommended and no longer present in the current Brazilian recommendation) and 4 fungicide application conditions (no application; one application at 60 days after emergence (DAE); two applications, 60 and 75 DAE; and three applications, at 60, 75, 90 DAE), with three repetitions.   Results and conclusion: The oat cultivars URS Altiva, URS, Guará, URS Charrua, FAEM 4 Carlasul, IPR Aphrodite, and UPFPS Farroupilha showed satisfactory yields in absence of fungicide applications. URS Altiva, FAEM 4 Carlasul, and IPR Aphrodite showed significant yield increases with fungicide application before grain filling. Artificial neural networks are efficient in predicting productivity and are a reliable alternative for simulating scenarios to validate more sustainable management practices.   Originality/value: An unprecedented study seeking more sustainable managements to reduce the use of fungicides in the control of oat diseases and development of simulation models by artificial intelligence, providing opportunities for analysis of different scenarios of the complex interaction plant, pathogen, and environment.