Drought Resilience in Wine Grapes: Genotypic Influence on Leaf Micronutrient Dynamics

This study aimed to examine variations in the micronutrient content of leaves in two-year-old indigenous and widely recognized grapevine cultivars under different levels of water stress. Eight wine grape cultivars (‘Adakarası,’ ‘Papazkarası,’ ‘Karasakız,’ ‘Karalahana,’ ‘Yapıncak,’ ‘Vasilaki,’ ‘Cabernet Sauvignon,’ and ‘Sauvignon Blanc’) were grown in pots as own-rooted plants and subjected to five distinct irrigation treatments—100%, 75%, 50%, and 25% of available water capacity (AWC), as well as the no-irrigation condition. The experiment was conducted over two consecutive years, from May to September, using a computer-controlled nutrition and irrigation system under semi-controlled conditions. The findings revealed that, except for sodium (Na), all micronutrient concentrations in leaf tissues increased in the second year of the study. The response of leaf micronutrient content to varying AWC levels was predominantly influenced by the cultivars' genotypic characteristics rather than the irrigation regime. Additionally, significant correlations were observed among micronutrient levels.