Original Research ARTICLE
Controversies in the midday water potential regulation and stomatal behauvior might result by the environment, genotype and/or roostock: evidence from Carménère and Syrah grapevine varieties.
- 1Agricultural Production, Faculty of Agricultural Sciences, University of Chile, Chile
- 2University of Chile, Chile
Controversies exist regarding the iso/anisohydric continuum for classifying plant water use strategies. Isohydricity has been argued to result from a plant-environment interaction, rather than an intrinsic property of the plant. Discrepancies remains regarding the degree of isohydricity () of plants and their threshold for physiological responses and resistance to drought. Thus, the aim of this study was to evaluate the isohydricity of the grapevine varieties Syrah and Carménère through a non-lethal water deficit progression from veraison on different locations: Cachapoal Valley (CV) and Maipo Valley (MV), in central Chile, and with different rootstock only in Syrah. For this purpose, the midday water potential (md) regulation and stomatal responses to drought, leaf traits related to pressure-volume curves, stomatal sensitivity to ABA, cavitation threshold and photosynthetic responses were assessed. A higher atmospheric water demand was observed in the CV compared to the MV, with lower md values in the former for both varieties. Also, the values in Carménère were 1.11 0.14 MPa MPa-1 and 0.68 0.18 MPa MPa-1 in the CV and MV, respectively, and in Syrah was 1.10 0.07 MPa MPa-1 in the CV and 0.60 0.10 MPa MPa-1 in the MV. Even though similar variations in between locations in both varieties were evident, Carménère plants showed a conserved stomatal response to md in both study sites, while those of Syrah resulted in a higher stomatal sensitivity to md in the site of lower . Besides the differences in seasonal weather conditions, it is likely that the different rootstock and clonal variability on each season in Syrah was able to induces coordinated changes in gs12 and osmotic potential at full turgor (0). On the other hand, irrespective of the , and given the similarity between the 0 and gs12 in leaves before drought, it seems that0 could be a convenient tool for assessing the md threshold values posing a risk to the plants, in order to aid the irrigation decision making in grapevines under controlled water deficit. Finally, water deficit in vineyards might be irreversibly compromising the photosynthetic capacity of leaves.
Keywords: water relations, Vitis vinifela L., drough, Isohydricity, leaf traits
Received: 09 Jul 2019;
Accepted: 31 Oct 2019.
Copyright: © 2019 Villalobos-González, Muñoz-Araya, Franck and Pastenes. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Mr. Luis Villalobos-González, Faculty of Agricultural Sciences, University of Chile, Agricultural Production, Santiago, 882 08 08, Santiago Metropolitan Region (RM), Chile, email@example.com
Dr. Claudio Pastenes, Faculty of Agricultural Sciences, University of Chile, Agricultural Production, Santiago, 882 08 08, Santiago Metropolitan Region (RM), Chile, firstname.lastname@example.org