CHANGES IN BERRY COLORATION AND RESISTANCE OF TABLE GRAPE CULTIVARS (Vitis vinifera L.) IN RESPONSE TO DIFFERENT GROWTH CONDITIONS OF SOILLESS CULTURE AND VINEYARD CULTIVATION

Abstract

Extreme climatic conditions resulting from global climate change became a challenging problem adversely affecting the sustainability of horticulture crops. Inconvenient climatic events seriously affect the plant physiology and metabolisms. Poor coloration is one of such problems frequently occurred in both table and wine grapes recently. Soilless culture in protected agriculture is one of the safest methodologies for coping with the negative effects of climate change on grapevines. Therefore, this study was performed to reveal the changes in berry quality, such as coloration and skin resistance of table grape cultivars Alphonse Lavallée’, ‘Italia’ and ‘Prima’ (Vitis vinifera L.) in response to different growth conditions of soilless culture and vineyard cultivation. Bilateral cordon pruned grapevines of each cultivar were cultivated in two different conditions as soilless culture (solid medium of peat and perlite mixture) in glasshouse and open area vineyard (1.2 x 2.7 m). The midday air temperatures in glasshouse of soilless culture reached about 37°C for many days, while other lots of the study grapevines experienced a temperature not higher than 33°C, during the berry growth stages. Skin color features, such as lightness, chroma and Hue angle values changed remarkably depending on the cultivars in response to growth conditions. But berry skin rupture force was obviously higher in grapes from soilless culture than those of vineyard condition. Viticulturists should, thus, consider new production techniques under multiple stress conditions, such as soilless culture under protected agriculture to improve berry coloration and resistance because the skin features of grapes are among the pioneering agronomic features determining the visual or biochemical quality properties.