A. de O. Rios, and V. Manfroi. 2020. Characterization of feijoa fermented beverage. Int. J. Agric. Nat. Resour. This study aimed to prepare a feijoa wine and to assess its physicochemical parameters, bioactive compounds, and antioxidant activity. Feijoa were harvested at physiological maturation, and their pulp was fermented in a BOD device at 16 ± 2 °C for 15 days. After the fermentation process, the beverage was characterized for its physicochemical parameters, total phenolic compounds and total flavonoids by spectrophotometry, carotenoids by HPLC, and antioxidant activity by the FRAP, DPPH, and ABTS methods. These same analyses were performed on the pulp in natura for comparative and evaluation purposes of the process. The feijoa fermentation process had a high yield (82%), and the physicochemical characteristics were in accordance with this class of beverage. The beverage had high antioxidant activity, while six carotenoids were identified in the fruit in natura, with (all)-trans-lutein and β-cryptoxanthin being the major carotenoids, in addition to a phenolic content of 176.22 mg GAE 100 g-1 and a total flavonoid content of 0.11 mEq quercetin 100 g-1. The wine had a lower bioactive compound content but a higher antioxidant activity than the pulp. Feijoa wine is a viable technological product in addition to exhibiting antioxidant activity.

Prohexadione-calcium (ProCa) is a gibberellin biosynthesis inhibitor and the objective of this study was to evaluate the effect of ProCa on the downy mildew (DM) and Botrytis bunch rot (BBR) epidemiology, and the yield and technological and phenolic parameters of grape Merlot cultivar. Experiments were carried out in a commercial vineyard in São Joaquim Municipality/SC, Southern Brazil, during the 2017-2018 and 2018-2019 growing seasons. ProCa was applied at four doses and three phenological stages: A) 0 g ha−1 (control); B) 1000 g ha−1 (inflorescence fully developed); C) 500 + 500 g ha−1 (inflorescence fully developeted and full flowering); D) 500 + 500 + 500 g ha−1 (inflorescence fully developed, full flowering, and berries pea-sized). DM and BBR incidence and severity were quantified weekly from the first symptom appearance until harvest, and their epidemiology was compared according to: a) the beginning of symptom appearance; b) the time to reach the maximum disease incidence and severity; c) the maximum value of disease incidence and severity; d) the area under the disease progress curve. In general, there were significant differences in the ProCa doses for all epidemiologic parameters of DM and BBR compared with the control plot; however, there was no significant difference among the ProCa doses. The principal epidemiological variables that differentiated the effect of ProCa on the DM and BBR control were the Smax and AUSDPC. Some yield and technological and phenolic parameters were negatively affected by different doses of ProCa, but it was still a good option for DM and BBR control in highland region of southern Brazil during the 2017-2018 and 2018-2019 growing seasons.

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