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ABSTRACT The use of resistant cultivars is the main strategy to control Fusarium wilt on tomato, caused by Fusarium oxysporum f. sp. lycopersici . This study aimed to quantify the incidence and distribution of this disease in the region of Nova Friburgo, RJ, as well as the type of resistance of tomato cultivars to the three FOL races. Samples of healthy and wilted plants from 40 properties were evaluated for the presence of vascular discouloration. Seventeen tomato cultivars were evaluated for resistance to the three FOL races using a grading scale. Classification for resistance/susceptibility, incidence and percentage of infection of the vascular system, fresh weight accumulation and seedling length were determined. All the cultivars analysed behaved as similar to immune (SI) to race 1 of FOL and similar to immune or partial resistance to race 2. Only Aguamiel cultivar presented a SI reaction to FOL race 3. None of the cultivars presented a SI reaction to the three races. It can be concluded that failures on the control of the disease in this region can be attributed to the majority use of cultivars with incomplete resistance to the three FOL races. The seed packages also contain incomplete information about FOL resistance.

A produção de couve-flor e demais brássicas vem sendo impactada, a nível mundial, devido à ocorrência da doença hérnia das crucíferas, causada por Plasmodiophora brassicae (Wor.). Diante disso, torna-se necessário a busca por estratégias de manejo que possam contribuir na redução das perdas causadas pela doença. Este trabalho objetivou, de forma preliminar, avaliar os efeitos de diferentes doses de torta de mamona (TM) na severidade da hérnia das crucíferas e no crescimento de plantas de couve-flor. Foram realizados dois ensaios em casa de vegetação onde, no primeiro, avaliou-se em tubetes os efeitos das doses 0, 10, 20 e 40 Mg ha-1 de TM na incidência da doença e na massa seca da parte aérea (MSPA). No segundo, avaliou-se em vasos as doses 0, 10, 20, 30 e 40 Mg ha-1 na severidade da doença, atributos das raízes e acúmulo de biomassa nas plantas. Foram observadas diferenças significativas quanto à incidência da doença, que foi reduzida, e da MSPA que aumentou em função das doses. Houve decréscimos na severidade da doença e incrementos no crescimento das raízes sadias. Adicionalmente, observaram-se efeitos positivos na altura das plantas, número de folhas e massa seca de folhas, caules e raízes. Conclui-se que a utilização de torta de mamona foi promissora nas condições analisadas e que novos estudos devem ser realizados em condições de campo e com ciclo mais longo.

Clubroot, caused by Plasmodiophora brassicae, is a disease that limits the cauliflower cultivation and is difficult to control. This study aimed to evaluate the efficiency of liming combined with the use of Trichoderma harzianum-based biofungicide for the control of clubroot in cauliflower. In a field experiment, the use of the biofungicide in combination with the application of calcined limestone doses (0 Mg ha-1, 1.0 Mg ha-1, 2.0 Mg ha-1 and 4.0 Mg ha-1) was evaluated. Subsequently, in a greenhouse, the biofungicide combined with liming with quicklime (2.54 Mg ha-1) was tested, and cyazofamid and water were tested as controls. The disease severity and attributes related to root and plant development were analyzed. In the field experiment, the healthy root volume and fresh weight, total root dry weight and inflorescence fresh weight and diameter were all significantly increased, while the diseased root volume, in response to the limestone doses, was reduced. The biofungicide reduced the root growth and inflorescence fresh weight. In the greenhouse, liming increased the healthy root volume and fresh weight, as well as total root dry weight, and reduced the disease severity. No significant difference was observed between the biofungicide and the control (water), which were inferior to cyazofamid. The biofungicide was not efficient in controlling the disease and did not favour the growth of cauliflower plants, either alone or combined with liming. Liming reduced the disease severity and increased the cauliflower root growth and yield.