Evaluation of different tools to measure water status in vines (Vitis vinifera L.) with cv. Tempranillo blanco

Abstract

Different irrigation treatments were applied in vines (Vitis vinifera L.) with cv. Tempranillo blanco during 2016 in an experimental field located in Rincón de Soto (La Rioja, Spain), 42°12’37″N; 1°52’36″W. In the R2 treatment, the irrigation treatment applied was equivalent to 30% of the crop evapotranspiration (ET₀) from the phenological stage of fruit-setting until harvest; in R5, irrigation with 60% of ET₀ from the phenological stage of fruit-setting until harvest; in R5D, an equivalent treatment to R5 but with early thinning of leaves at the beginning of blooming; and in R0, treatment without irrigation. Measures of water potential and stomatal conductance were taken throughout the vine cycle with the purpose of determining the water status of plants and establishing possible correlations between both parameters. At the same time, reflectance and fluorescence measures were taken in order to determine the nutrient and water status within the different treatments. High correlations were found between the measure of water potential and the measures of stomatal conductance, reflectance and fluorescence. In the no-irrigation treatment (R0) and in the treatment with early thinning of leaves (R5D) the obtained yield was significantly reduced. Both treatments showed the lowest levels of total acidity in wines while, on the other hand, in the treatment with higher doses of irrigation (R5), the highest levels of this parameter were found.