Evaluation of amino acid contents and enzyme activities of seeds from Semillon and Carignane wine grape cultivars grown under different irrigation conditions

Abstract

The effects of deficit irrigations (DI50, DI75) and full irrigation (FI100) level together with control (Rainfed) treatment on amino acid contents and enzyme activities of seeds of Semillon and Carignane wine grape varieties were evaluated. Irrigation was started when the midday leaf water potential reached -10 bars. Accordingly, irrigation was initiated after berry set and continued at weekly intervals until the harvest time in the study area. To calculate of water volumes applied to the irrigated plots were considered 50%, 75% and 100% of the cumulative evaporation from the Class A Pan for a week duration. The results of this study showed that irrigation affected the phytochemical parameters in both cultivars. In terms of glutathione S-transferase enzyme activity and amino acid contents (except aspartate), Semillon gave higher values than those of Carignane. However, values of glutathione and catalase enzyme activities, quaternary amines and aspartate amino acids were higher in Carignane. Phytochemical contents of the seeds changed according to the irrigation levels. Generally, the values of quaternary amines, dehydrins and histidine, cystine, lysine, proline in amino acids considerably increased in the control and DI50 treatments. However, there were no significance differences in terms of amino acids (glutamine, glycine, thionine, arginine, hydroxy proline and sarcosine) among the irrigation levels. As a result of the study, it can be concluded that the amounts of compounds analyzed in the grape seeds increased with rainfed and deficit irrigation together with the rainfall under experimental conditions.