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RESUMOPalavras-chave adicionais: cinamomo, agroecologia, extratos vegetais, produção orgânicaThe aim of this study was to evaluate the effect of aqueous extract of chinaberry (Melia azedarach L.) on Elsinoe ampelina, the etiological agent of grapevine anthracnose, and on the disease control. For the trials of mycelial growth, sporulation and conidium germination, the concentrations 0, 10, 20, 30, 40 and 50 mL L -1 extract were used, besides standard treatments with bordeaux mixture and mancozeb. Under field conditions, an experiment was conducted in a commercial vineyard for two consecutive cycles (2009/2010, 2010/2011) to evaluate increasing concentrations of extract and vegetable oil (2.5 mL L -1 ), in addition to an absolute control (without treatment) and standard treatment with bordeaux mixture. Concentrations equal to or higher Silva, C.M.; Botelho, R.V.; Faria, C.M.R.D. Use of aqueous extract of chinaberry to control grapevine anthracnose. Summa Phytopathologica, v.38, n.4, p.312-318, 2012. than 20 mL L -1 extract led to complete inhibition of sporulation. The concentration of 50 mL L -1 decreased by 99.4% the colony diameter and did not differ from the treatment with bordeaux mixture, besides reducing conidium germination by 84.8 and 90.8%, compared to control, at 12 and 24 hours after incubation. In the first year of the experiment in the field, there was a negative linear effect of extract concentrations on anthracnose severity. However, in the second year, the use of vegetable oil as adjuvant masked the extract effect. The isolate application of vegetable oil reduced AUDPC by 64.0%, which is similar to the results obtained with all concentrations of chinaberry extract and the standard treatment with bordeaux mixture.O objetivo desse trabalho foi avaliar o efeito do extrato aquoso de cinamomo (Melia azedarach L.) sobre Elsinoe ampelina, agente etiológico da antracnose da videira, e no controle da doença. Para os experimentos de crescimento micelial, esporulação e geminação de conídios do fungo foram utilizadas as concentrações de 0, 10, 20, 30, 40 e 50 mL L -1 de extrato, além dos tratamentos padrões com calda bordalesa e mancozebe. Em condições de campo, um experimento foi conduzido em vinhedo comercial por dois ciclos consecutivos (2009/2010, 2010/2011) Additional keywords: chinaberry, agroecology, plant extracts, organic production. ABSTRACTA videira é economicamente uma das mais importantes fruteiras cultivadas no mundo, devido às inúmeras utilizações dos seus frutos para consumo in natura e processamento. As doenças fúngicas constituem-se como sendo um dos principais problemas de interesse econômico na viticultura, em consequência das perdas registradas. Conforme Sônego & Garrido (28), dentre as principais doenças fúngicas, destaca-se a antracnose, causada por Elsinoe ampelina (de Bary) Shear e responsável por grandes danos para a viticultura no sul do Brasil, assim como em outras regiões vitícolas do mundo.A antracnose da videira é uma doença de origem européia que reduz a qualidade e a quan...

RESUMOEste trabalho teve como objetivo avaliar o efeito do extrato aquoso de cinamomo (Melia azederach) no controle de Plasmopara viticola. Para o teste de germinação de esporângios do oomiceto foram utilizadas as concentrações de 0, 5, 10, 15, 20 PALAVRAS-CHAVES:Vitis vinifera, lírio-da-índia, agroecologia, Plasmopara viticola, Melia azederach. ABSTRACT ALTERNATIVE CONTROL OF DOWNY MILDEW WITH AQUEOUS EXTRACTS OF CHINA-BERRY AND VEGETABLE OIL.The aim of the present study was to evaluate the effect of aqueous extract of chinaberry (Melia azedarach) in the control of Plasmopara viticola. For the germination test of sporangia of the oomycete, concentrations of 0, 5, 10, 15, 20 and 25 mL L -1 of aqueous extract of chinaberry (EC) were used, as well as treatments with mancozeb and bordeaux mixture. The experiment in the greenhouse and field involved concentrations of 0, 30, 40 and 50 mL L -1 of EC (1:10 w/v) and a treatment with bordeaux mixture (1:1:100 ). In the second experiment in the field the treatments were: 0, 10, 20, 30, 40 and 50 mL L -1 of EC with an added 2.5 mL L -1 of vegetable oil, the bordeaux mixture and an absolute control. In the germination test, there was highest inhibition of P. viticola at 2 hours after incubation at 20° C, for the 20 and 25 mL L -1 concentrations of the EC, with a reduction of 66.5 and 62.0%, respectively. In the greenhouse conditions, the EC at a concentration of 40 and 50 mL L -1 showed a reduction of 70.0% and 86.0% of the disease, respectively, while the same concentrations in the first cycle of the field experiment showed a decrease of 34.0% and 31.0%, respectively. However, in the second cycle, the use of vegetable oil as an adjunct masked the effect of the EC, and the isolated application of vegetable oil decreased the area under the disease progress curve (ADPC) by 76.3%, similar to results obtained with all concentrations of EC and with the bordeaux mixture.