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RESUMO Entre as doenças que causam manchas foliares no algodoeiro, a mancha de ramulária tem se tornado importante em ambientes tropicais, porque as condições climáticas são favoráveis para o desenvolvimento do patógeno. Objetivou-se nesse trabalho avaliar o desempenho dos fungicidas difenoconazol, trifenil hidróxido de estanho, trifloxistrobina, protioconazol e mancozebe, isolados ou em misturas, no controle da mancha de ramulária no algodoeiro. O experimento foi conduzido na safra 2014/2015, em uma fazenda localizada no município de Sapezal, estado do Mato Grosso. O delineamento experimental foi em blocos casualizados e quatro repetições, com parcelas subdivididas no tempo. Foram realizadas sete avaliações de níveis de severidade da mancha da ramulária nos sete tratamentos. Os fungicidas foram aplicados oito vezes, em intervalos de 15 dias. Ao final do período experimental, foi avaliada a produtividade e a eficiência de controle dos fungicidas em comparação com a testemunha. A aplicação de fungicidas reduziu os danos de produtividade devido ao ataque italico fungo Ramularia areola. O trifenil hidróxido de estanho, isolado ou em mistura com o difenoconazol permitiu maior controle da severidade da mancha de ramulária do que a combinação de trifloxistrobina + protioconazol com difenoconazol, ou difenoconazol com mancozebe. ABSTRACT Among the diseases that cause leaf spots in the cotton crop, ramularia leaf spot has become important in tropical environments since the weather conditions are favorable to the pathogen development. The aim of this study was to evaluate the performance of fungicides difenoconazole, triphenyltin hydroxide, trifloxystrobin, prothioconazole and mancozeb, alone or in mixtures, in controlling ramularia leaf spot in the cotton crop. The experiment was carried out in the 2014/2015 crop season, at a farm located in Sapezal Municipality, Mato Grosso State. Experimental design was in randomized blocks with four replicates and split plot in time. Seven evaluations of ramularia spot severity levels were performed with seven treatments. Fungicides were applied eight times, at 15-day intervals. At the end of the experimental period, the yield and the control effectiveness of fungicides were evaluated in comparison with control. Fungicide applications reduced yield damage caused by the attack of the fungus Ramularia areola. Triphenyltin hydroxide alone or in combination with difenoconazole allowed greater control of ramularia spot severity than the combination of trifloxystrobin + prothioconazole with difenoconazole, or diphenoconazole with mancozeb.

Dithiocarbamates are widely used fungicides, including in passion fruit, whose fruits are mainly used for juice production, the leaves for the preparation of herbal tea and medicines. Also, the use of the peel in the food industry has been proposed. In this study, the spectrophotometric method for determination of dithiocarbamate residues, as CS2, in passion fruit (Passiflora edulis) was validated at a limit of quantification (LOQ) of 0.05 mg kg-1 CS2, and 108 samples (55 fruits and 53 leaves) collected from Brazilian growers were analyzed. About 25% of the fruit peel samples were positive (0.06 to 1.4 mg kg-1) and only one sample had residues in the pulp (0.09 mg kg-1), 43.4% of leaf samples contained residues. Washing of fruit reduced the residues in the peel by up to 100%, and drying the leaves increased residue levels by up to 60%. This is the first study that reports dithiocarbamate residues in passion fruit in Brazil, and the results are important for government authorities when planning monitoring programs, and for food and herbal medicine industries.

Apple scab (Venturia inaequalis) is the most important disease in Chilean apple (Malus domestica Borkh.) orchards where fungicide management is the main tool to control disease. Sensitivity tests to difenoconazole, fenarimol, mancozeb, and pyrimethanil fungicides were conducted on V. inaequalis wild isolates to construct local baseline sensitivity distributions, and compare them with a collection of isolates from seven different commercial orchards with no evidence of practical resistance. In vitro assays were conducted and sensitivity was measured as inhibition of mycelial growth (difenoconazole, fenarimol, pyrimethanil) or conidial germination (mancozeb). Departure from the baseline distribution to less sensitivity was found for difenoconazole, fenarimol, and mancozeb with resistance factors of 4.7, 5.8, and 2.1, respectively. The highest difference between baseline and orchard populations was observed for fenarimol which showed the highest shift to less sensitivity. Discriminatory doses of 0.04, 1.0, 0.6, and 0.2 µg mL-1 are proposed for in vitro monitoring of sensitivity to difenoconazole, fenarimol, mancozeb, and pyrimethanil, respectively.La sarna del manzano (Venturia inaequalis) es la principal enfermedad del cultivo en Chile y es controlada principalmente con el uso de fungicidas. Se realizaron pruebas de sensibilidad a los fungicidas difenoconazole, fenarimol, mancozeb y pyrimethanil en aislados monoconidiales de cepas silvestres de V. inaequalis con el fin de elaborar curvas basales de sensibilidad y compararlas con la sensibilidad de una colección de aislados monoconidiales provenientes de siete huertos comerciales sin evidencias de resistencia práctica. Se realizaron pruebas in vitro donde la sensibilidad se midió como la inhibición del crecimiento miceliar (difenoconazole, fenarimol y pyrimethanil) o la inhibición de la germinación de conidias (mancozeb). La población de huertos comerciales estudiada presentó una menor sensibilidad a los fungicidas difenoconazole, fenarimol y mancozeb con valores de factor de resistencia 4,7; 5,8; y 2,1 para difenoconazole, fenarimol y mancozeb, respectivamente. La mayor diferencia de sensibilidad entre la población silvestre y la de huerto se obtuvo con feranimol, fungicida para el cual se observó el mayor cambio hacia una menor sensibilidad. Se proponen dosis discriminatorias de 0,04; 1,0; 0,6; y 0,2 µg mL-1 para difenoconazole, fenarimol, mancozeb y pyrimethanil, respectivamente.

Avaliou-se o efeito do tirame, ditiocarbamato largamente utilizado na agricultura como antifúngico e repelente de roedores, na ossificação endocondral de mamíferos, usando, como modelo, ratos Wistar. Não foram observadas lesões na cartilagem articular, nem nas placas de crescimento, o que pode ser atribuído à dose utilizada e à duração do ensaio. A diminuição da altura da placa de crescimento nos animais aos quais foi administrado o tirame parece traduzir o atraso verificado no crescimento em geral, e não um efeito específico na cartilagem, uma vez que as diferentes zonas da placa epifisária mantiveram as proporções dos animais do grupo-controle. Embora não tenham sido verificados, no presente trabalho, os efeitos registrados para outras espécies nos tecidos cartilaginosos, sugere-se a avaliação dos efeitos crónicos do tirame no crescimento e no desenvolvimento dos ossos longos em mamíferos.

Apple scab (Venturia inaequalis) is the most important disease in Chilean apple (Malus domestica Borkh.) orchards where fungicide management is the main tool to control disease. Sensitivity tests to difenoconazole, fenarimol, mancozeb, and pyrimethanil fungicides were conducted on V. inaequalis wild isolates to construct local baseline sensitivity distributions, and compare them with a collection of isolates from seven different commercial orchards with no evidence of practical resistance. In vitro assays were conducted and sensitivity was measured as inhibition of mycelial growth (difenoconazole, fenarimol, pyrimethanil) or conidial germination (mancozeb). Departure from the baseline distribution to less sensitivity was found for difenoconazole, fenarimol, and mancozeb with resistance factors of 4.7, 5.8, and 2.1, respectively. The highest difference between baseline and orchard populations was observed for fenarimol which showed the highest shift to less sensitivity. Discriminatory doses of 0.04, 1.0, 0.6, and 0.2 µg mL-1 are proposed for in vitro monitoring of sensitivity to difenoconazole, fenarimol, mancozeb, and pyrimethanil, respectively. La sarna del manzano (Venturia inaequalis) es la principal enfermedad del cultivo en Chile y es controlada principalmente con el uso de fungicidas. Se realizaron pruebas de sensibilidad a los fungicidas difenoconazole, fenarimol, mancozeb y pyrimethanil en aislados monoconidiales de cepas silvestres de V. inaequalis con el fin de elaborar curvas basales de sensibilidad y compararlas con la sensibilidad de una colección de aislados monoconidiales provenientes de siete huertos comerciales sin evidencias de resistencia práctica. Se realizaron pruebas in vitro donde la sensibilidad se midió como la inhibición del crecimiento miceliar (difenoconazole, fenarimol y pyrimethanil) o la inhibición de la germinación de conidias (mancozeb). La población de huertos comerciales estudiada presentó una menor sensibilidad a los fungicidas difenoconazole, fenarimol y mancozeb con valores de factor de resistencia 4,7; 5,8; y 2,1 para difenoconazole, fenarimol y mancozeb, respectivamente. La mayor diferencia de sensibilidad entre la población silvestre y la de huerto se obtuvo con feranimol, fungicida para el cual se observó el mayor cambio hacia una menor sensibilidad. Se proponen dosis discriminatorias de 0,04; 1,0; 0,6; y 0,2 µg mL-1 para difenoconazole, fenarimol, mancozeb y pyrimethanil, respectivamente.