The fate of five fungicide residues (azoxystrobin, fluazinam, kresoxim-methyl, mepanipyrim, and tetraconazole) from vine to wine was studied, to evaluate the decay ratio and study the influence of the technological process. The disappearance rates on grapes were described as pseudo-first-order kinetics (r between 0.96 and 0.99) and half-life (t 1/2) in the range of 4.3−15.2 days. After wine-making, fluazinam, mepanipyrim, and tetraconazole had negligible residues in all samples. This was due to fermentation in the case of fluazinam and mepanipyrim and to removal during the formation of must in the case of tetraconazole. The residue level of azoxystrobin was higher in the wine obtained by vinification without maceration than with maceration. Azoxystrobin was the only active ingredient found in both grapes and wine. The clarifying process showed that among the clarifying agents used, only charcoal was efficient in decreasing the residues completely. Keywords: Fungicide; residues; wine-making; grape

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ResumenEsta investigación tuvo como objetivo la identificación del agente causal del mildiú de la albahaca y la validación de un método de estimación de la severidad. El patógeno presenta morfométricamente zoosporangióforos monopodiales y ramificados dicotómicamente en ángulo agudo hasta 4,25 veces en la parte terminal, un largo de 320,1 µm; esterigmas cortos de 15,5 µm y de 17,9 µm de largo. Los zoosporangios, ligeramente ovoides con 27,7 µm de diámetro y con 31,9 µm de largo. La estimación de severidad se realizó por el método de Horsfall y Barratt (HB) (Horsfall y Barratt, 1945), por estimación visual directa (VD) y evaluando daño foliar por cada tercio de la planta (TH). La evaluación aleatoria se realizó en tres oportunidades por tres evaluadores, y los valores estimados fueron correlacionados con la severidad real. Para medir la confiabilidad entre evaluadores y métodos de evaluación se empleó el coeficiente de correlación y concordancia (CCC). En el método VD, los tres evaluadores obtuvieron valores de 0,57; 0,63 y 0,44 respectivamente; en el método de HB fueron 0,58; 0,46 y 0,42 y en TH 0,14; 0,08 y 0,52. Se concluye que, el agente causal del mildiú de la albahaca es Peronospora belbahrii y según el CCC el mejor método de evaluación fue el de la estimación visual directa. Palabras clave: mildiú albahaca; severidad estimada; severidad real; coeficiente de correlación; Peronospora belbahrii; Ocimum basilicum.

The flowers blight caused by Botrytis cinerea Pers. is among the most important citrus diseases, especially in cultivars whose flowering coincides with the humid seasons of the year. As a result of the pathogenic features of this fungus and the complex nature of its control, it is necessary to establish a correct plan for the usage of highly efficient fungicides. The study aimed to evaluate the effect of four chemical fungicides, such as Captan (0.25%), Propineb (0.25%), Fludioxonil + Cyprodinil (0.05%), and Iprodione (0.15%); as well as the effect of a biological fungicide, such as Melaleuca alternifolia extract (0.1%), on Botrytis cinerea Pers. Two phases were established: the first, under laboratory conditions of Department of Plant Pathology of National Agrarian University-La Molina (UNALM), evaluated the effect on mycelial inhibition at 1, 3, and 7 days after inoculation with poisoned potato dextrose agar medium. The second, under field conditions (Sayan -Huaura), evaluated the effect on incidence of the disease in flowers. In the field condition, two applications, incidence, and humid chambers were evaluated. The yield was estimated by counting the fruits. The results showed that, under laboratory conditions, Captan, Fludioxonil + Cyprodinil, and Iprodione exhibited high efficacy in the control of B. cinerea. However, under field conditions, Fludioxonil + Cyprodinil and Iprodione exhibited a significant control of B. cinerea. A similar trend was obtained for the yield estimates.