Giesco
21st GiESCO International Meeting: ‘A Multidisciplinary Vision towards Sustainable Viticulture’ CHANGES IN PHENOLIC MATURITY AND TEXTURE CHARACTERISTICS OF THE GRAPE BERRY UNDER PRE-, AND POST-VERAISON WATER DEFICIT 1 2 2 3 1 1
Zsolt ZSÓFI ; Ottó BENCSIK ; András SZEKERES ; Xénia PÁLFI ; Ádám BOZÓ ; Szabolcs VILLANGÓ 1 ESZTERHÁZY KÁROLY UNIVERSITY, DEPARTMENT OF VITICULTURE AND OENOLOGY, Leányka str. 6, Eger H3300 Hungary. 2 UNIVERSITY OF SZEGED, DEPARTMENT OF MICROBIOLOGY, Közép fasor 52., Szeged, H-6726 Hungary, 3 ESZTERHÁZY KÁROLY UNIVERSITY, FOOD AND WINE RESEARCH INSTITUTE, Leányka str. 6., Eger, H-3300, Hungary *Corresponding author: zsofi.zsolt@uni-eszterhazy.hu
Abstract: Context and purpose of the study - Kékfrankos (Vitis vinifera L.) grapevines grafted on Teleki-Kober 5BB rootstock were submitted to water deficit under greenhouse conditions. The aim of the experiment was to study the effect of pre-, and post-veraison water deficit on grape berry phenolic maturity and texture characteristics. Material and methods - Plants were planted into 50L white plastic containers in a mixture of perlite (20%), loamy soil (30%) and peat (50%) (v/v). Three regimes of water supply were examined: (1) moderate water deficit from berry set until veraison (WD1), (2) moderate water deficit from veraison until harvest (WD2), (3) no water deficit (C). The water deficit treatments defined by the leaf daily stomatal conductance (between 50-150 H 2O mmol m-2s-1). Anthocyanin glucosides and flavonols from berry skin were measured by Shimadzu HPLC system, berry texture characteristics were monitored by TA.XT Plus Texture Analyser. Cell and seed maturity indexes (CMI%, SMI%) and basic parameters (yield, sugar concentration, pH, must acidity) were also investigated. Results - Pre-veraison treatment resulted in the lowest berry and cluster weight. The highest sugar concentration was found in control berries, and it was followed by the WD1 and WD2 treatments. Berries of the well-watered plants presented the lowest phenolic concentration. Pre-veraison water deficit resulted in a sllighty higher concentration of anthocyanin-glucosides compared to post-veraison water deficit. Water restriction during the ripening period induced higher flavonol (ie. quercetin, kaempferol etc.) concentration related to berry skin fresh weight as well as to the whole berry compared to WD1 treatment. Berry skin hardness (Fsk) was the highest in the case WD2 and the lowest was in WD1. Similar results were obtained in the case of berry skin thickness (S psk). Seed (SMI%) maturity index presented higher values in the case of WD treatments compared to C. Cell maturity index (CMI%) of WD2 was significantly higher than C and WD1, however no differences were found between C and WD1.
Keywords: Water deficit, Anthocyanin extractability, Phenolic maturity, Berry texture THE WORK WAS SUPPORTED BY EFOP-3.6.2-16-2017-00001 RESEARCH GRANTS AND BY THE SZÉCHENYI 2020 PROGRAMME, THE EUROPEAN REGIONAL D EVELOPMENT FUND AND THE H UNGARIAN GOVERNMENT (GINOP-2.3.2-15-2016-00061).
Abstract: Context and purpose of the study - Kékfrankos (Vitis vinifera L.) grapevines grafted on Teleki-Kober 5BB rootstock were submitted to water deficit under greenhouse conditions. The aim of the experiment was to study the effect of pre-, and post-veraison water deficit on grape berry phenolic maturity and texture characteristics. Material and methods - Plants were planted into 50L white plastic containers in a mixture of perlite (20%), loamy soil (30%) and peat (50%) (v/v). Three regimes of water supply were examined: (1) moderate water deficit from berry set until veraison (WD1), (2) moderate water deficit from veraison until harvest (WD2), (3) no water deficit (C). The water deficit treatments defined by the leaf daily stomatal conductance (between 50-150 H 2O mmol m-2s-1). Anthocyanin glucosides and flavonols from berry skin were measured by Shimadzu HPLC system, berry texture characteristics were monitored by TA.XT Plus Texture Analyser. Cell and seed maturity indexes (CMI%, SMI%) and basic parameters (yield, sugar concentration, pH, must acidity) were also investigated. Results - Pre-veraison treatment resulted in the lowest berry and cluster weight. The highest sugar concentration was found in control berries, and it was followed by the WD1 and WD2 treatments. Berries of the well-watered plants presented the lowest phenolic concentration. Pre-veraison water deficit resulted in a sllighty higher concentration of anthocyanin-glucosides compared to post-veraison water deficit. Water restriction during the ripening period induced higher flavonol (ie. quercetin, kaempferol etc.) concentration related to berry skin fresh weight as well as to the whole berry compared to WD1 treatment. Berry skin hardness (Fsk) was the highest in the case WD2 and the lowest was in WD1. Similar results were obtained in the case of berry skin thickness (S psk). Seed (SMI%) maturity index presented higher values in the case of WD treatments compared to C. Cell maturity index (CMI%) of WD2 was significantly higher than C and WD1, however no differences were found between C and WD1.
Keywords: Water deficit, Anthocyanin extractability, Phenolic maturity, Berry texture THE WORK WAS SUPPORTED BY EFOP-3.6.2-16-2017-00001 RESEARCH GRANTS AND BY THE SZÉCHENYI 2020 PROGRAMME, THE EUROPEAN REGIONAL D EVELOPMENT FUND AND THE H UNGARIAN GOVERNMENT (GINOP-2.3.2-15-2016-00061).