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Mestrado em Engenharia Agronómica - Hortofruticultura e Viticultura - Instituto Superior de Agronomia This study aims to contribute to the diagnosis of brown spot of spitzkool cabbages, clarifying symptoms associated with the disease and its evolution in the final stage of field. We identified the causative agent of the disease as Stemphylium sp. by classical methods of mycology and sequencing fragments amplified by PCR of DNA purified from cabbage leaves with injuries, which has shown very significant homologies with the fungal genus Stemphylium. We tested the biological efficacy of six fungicides for Stemphylium sp. in in vitro studies. The mycelial growth was inhibited by more evidence fungicide pyraclostrobin + boscalid, pyraclostrobin and difenoconazole + dimethomorph. Based on these results, were selected pyraclostrobin and boscalid + difenoconazole to assess inhibition of spore germination. The fungicide used the first showed efficacy. We evaluated the disease from its onset in a field production, in field subjected to conventional treatments scheme and control field treated with water and refrigerated conditions. The disease was detectable one week before the harvest in the field treated with water, but over time disease developed in a stronger manner in the field treated with fungicides. During storage, room temperature conducted to the development of more spots in the cabbages that refrigeration conditions.