Evaluación de la tolerancia a estrés por sequía en cuatro genotipos naturalizados de vid (Vitis vinifera) provenientes del norte de Chile

the grapevine (vitis vinifera) is grown and characterized by seasonal drought suffered in most of the world's producing regions, a situation that increases in arid and semiarid regions of chile, which have experienced declines in rainfall and prolonged dry periods, one of the main problems that affect the productivity of the vines in these regions. the research aim was to analyze the morpho-physiological responses of naturalized grapevine genotypes exposed to water stress and determine their level of tolerance. physiological and architectural parameters were evaluated in four grapevine genotypes (10, 93, 134, 148), collected from a latitudinal gradient in arid and semi-arid northern chile (18° sl to 32° sl). by using a system of mini-rhizotrons, clonal material of the four genotypes was subjected to mild and severe (60% and 40% field capacity, respectively), water stress treatments during three months under a fully randomized design. significant differences were obtained at treatment's level for survival and stem length, internode distance and all physiological performance parameters evaluated. furthermore, there were significant differences between genotypes in traits such as root length, internode distance, photosynthesis and water potential. this allowed identifying anisohydric genotypes such as 134 and 148, from near isohydric genotypes, such as 10 and 93 in relation to the stress response behaviour. determination of early drought effects in development, survival, and physiological performance, allowed differentiating genotype 134 as the most tolerant of those assessed. this methodology will enable to select new genotypes for potential use as rootstocks or grafts for arid and semi-arid regions, emphasizing the fundamental role of exploring the grapevine genetic variability and its use as a crop model.