Defoliation, application of S-ABA and vegetal extracts on the quality of grape and wine Malbec cultivar

Abstract

High rainfall and low temperatures can cause grapes not to reach adequate maturation indexes. The aim of this work was to evaluate the effect of leaf removal, hormonal regulator and vegetable extracts on the quality of grape and wine. An experiment was conducted in a vineyard of Malbec cv.in southern Brazil by two consecutive seasons. Treatments were: 1) control, 2) manual defoliation in early maturation; 3) defoliation 15 days after the first defoliation; 4) S-ABA200 mg L-1; 5) S-ABA400 mg L-1; 6) S-ABA600 mg L-1. 7) vegetal Stachytarpheta cayenensis extract (100 g L-1) and 8) Cymbopogon citratus 100 g L-1. Diameter and length of canes, soluble solids, titratable acidity, anthocyanins and polyphenols in berry and wine, photosynthetically active radiation (PAR), chlorophyll index, defoliation percentage and leaf chlorosis and color index of berry skin were evaluated. Defoliation and S-ABA increased PAR. S-ABA provided leaf chlorosis and lowered the chlorophyll content, causing senescence. Defoliation and S-ABA increased the levels of total polyphenols, anthocyanins both in berry skin and wine of grapes Malbec cv. Vegetal extracts applied did not influence physical and chemical analyses, neither in anthocyanins and total polyphenols.

Modeling Pinot Noir Aroma Profiles Based on Weather and Water Management Information Using Machine Learning Algorithms: A Vertical Vintage Analysis Using Artificial Intelligence

“…Specifically, these effects manifest through the influence of the microclimate within bunches [49], phenolic compounds [50,51], and the flavonol profile [52]. Due to the direct effect of bunch exposure to radiation in the aroma profiles obtained in wines, researchers have investigated the effect of defoliation as a management strategy to increase berry quality and aroma traits, which depends on the cultivar, timing of defoliation, and climatic region [53][54][55][56][57][58][59][60]. These researches demonstrate the importance of fruit exposure to solar radiation and microclimate conditions that are favorable to the development of berry quality traits.…”

Influence of abscisic acid,Ascophyllum nodosumandAloe veraon the phenolic composition and color of grape berry and wine of 'Cabernet Sauvignon' variety

“…The maximum total concentration of polyphenols was associated with 600 mg/L in 'Isabel' grapes. Pessenti et al (2019Pessenti et al ( , 2020 also found an increase in anthocyanin content in 'Primitivo' and 'Malbec' varieties with the use of S-ABA at veraison stage.…”

Qualidade fenólica em cultivares de uva submetida a poda verde e regulador hormonal

“…Além disso, a relação entre flavonoides e compostos fenólicos sobre a qualidade do vinho é de extrema importância, especialmente em vinhos com potencial de envelhecimento e amadurecimento (Würz, Allebrandt, Filho, Bem, Brighenti, Outemane, et al, 2018). Pessenti et al (2019) verificaram que a aplicação de S-ABA proporcionou desfolha de até 60% na altura dos cachos com dose de 600 mg L -1 , isso contribui para o aumento de antocianinas e polifenóis totais na cv. Malbec.…”

“…A expressão das antocianinas depende de fatores internos, como o enântiomero S do ácido abscísico (S-ABA), que induz o fator de transcrição MYB1A, proteína encarregada de regular a transcrição de genes que compõem a rota biossintética das antocianinas das uvas tintas (Jeong et al, 2004;Pastore et al, 2013). Vários trabalhos sugerem que aplicações exógenas de S-ABA antecipam a época de colheita, aumentando as concentrações de antocianinas e proantocianinas nas cascas das uvas, com considerável melhoria em sua coloração, proporcionando maior uniformidade e qualidade (Koyama et al, 2019;Pessenti et al, 2019;Pessenti et al, 2017).…”