GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Consistency of the hydraulic traits and stomatal responses in grapevines with contrasting hydraulic vulnerability

Consistency of the hydraulic traits and stomatal responses in grapevines with contrasting hydraulic vulnerability

Abstract

Context and purpose of the study ‐ Different from wild species in arid and semiarid conditions, cultivated species are very sensitive to drought and, beyond some stress thresholds, food production is not possible. It is therefore important to gain further knowledge on the responses of plant species of agricultural importance to realistic water shortage extents, and their consistencies. A valuable model for water stress studies has been the grapevine (Vitis vinifera L.), a species with a high variability in their stomatal sensitivity to water stress. In contrast to usual agricultural practices, grapevines for oenological purposes are grown under controlled water stress conditions.

Material and methods ‐ In the abovementioned context, we aimed to study the physiological responses to a progressive, not severe (Ѱpd > ‐1MPa), water deficit in the grapevine varieties Syrah and Carménère, in two consecutive season using different sites each year, and with different row orientation. We assessed a) the relationship between the water status of plants and the stomatal responses to water availability; b) the hydraulic traits derived from Ѱ isotherms (pressure vs volume curves); c) the impact of the water stress on the hydraulic traits derived from the pressure vs volume curves and on photosynthetic responses; d) the stomatal sensitivity to ABA (only on one of the study sites) and e) their stem hydraulic vulnerability in relation to xylem characteristics.

Results – Acording to the Ѱleaf/Ѱpd relationship (), and contrary to various previous reports, we found Syrah to be an isohydric grapevine variety, while Carménère, an emblematic variety cultivated in Chile, behaved as anisohydric. Syrah resulted to be more variable in terms of , gs50 and gs12 (the pd upon which stomata is reduced down to a 50% and 12%), 0 and tlp (the at full turgor and the  at turgor loss point), likely associated to the higher genetic variability of Syrah compared to that of Carménère. Also, Carménère, the anisohydric variety was capable of osmotic adjustment and was more sensitive to ABA at the stomatal level, two traits typical of anisohydric species, contrary to that observed in Syrah. Even though the capacity to maintain stomata open, theoretically, would imply a lower energy load into the photosynthetic systems, both varieties reduced their photosynthetic capacity up to a similar extent upon drought. Finally, Syrah, despite having wider xylem vessels than Carménère, is less vulnerable to cavitation, and had a lower hydraulic safety margin, typical of isohydric species. We will discuss our results in terms of the genetic variability of the varieties regarding the consistency of their hydraulic responses, the importance of the environment, the degree of isohydry in relation to stomatal responses to critical thresholds as well as drought resistance, and the implications for photosynthesis in the long term. 

DOI:

Publication date: June 19, 2020

Issue: GiESCO 2019

Type: Article

Authors

Luis VILLALOBOS‐GONZÁLEZ (1), Constanza QUINTANA (1), Dayna DONAIRE (1), Mariana MUÑOZ‐ ARAYA (1), Nicolás FRANCK, Claudio PASTENES (1)

(1) Universidad de Chile, Facultad de Ciencias Agronómicas.

Contact the author

Keywords

ABA sensitivity, anisohydry, drought resistance, grapevine, stomatal conductance

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Aromatic maturity is a cornerstone of terroir expression in red wine

Harvesting grapes at adequate maturity is key to the production of high-quality red wines. Enologists and wine makers define several types of maturity, including technical maturity, phenolic maturity and aromatic maturity. Technical maturity and phenolic maturity are relatively well documented in the scientific literature, while articles on aromatic maturity are scarcer. This is surprising, because aromatic maturity is, without a doubt, the most important of the three in determining wine quality and typicity (including terroir expression). Optimal terroir expression can be obtained when the different types of maturity are reached at the same time, or within a short time frame. This is more likely to occur when the ripening takes place under mild temperatures, neither too cool, nor too hot. Aromatic expression in wine can be driven, from low to high maturity, by green, herbal, fresh fruit, ripe fruit, jammy fruit, candied fruit or cooked fruit aromas. Green and cooked fruit aromas are not desirable in red wines, while the levels of other aromatic compounds contribute to the typicity of the wine in relation to its origin. Wines produced in cool climates, or on cool soils in temperate climates, are likely to express herbal or fresh fruit aromas; while wines produced under warm climates, or on warm soils in temperate climates, may express ripe fruit, jammy fruit or candied fruit aromas. Growers can optimize terroir expression through their choice of grapevine variety. Early ripening varieties perform better in cool climates and late ripening varieties in warm climates. Additionally, maturity can be advanced or delayed by different canopy management practices or training systems.

‘Cabernet Sauvignon’ (Vitis vinifera L.) berry skin flavonol and anthocyanin composition is affected by trellis systems and applied water amounts

Trellis systems are selected in wine grape vineyards to mainly maximize vineyard yield and maintain berry quality. This study was conducted in 2020 and 2021 to evaluate six commonly utilized trellis systems including a vertical shoot positioning (VSP), two relaxed VSPs (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a guyot (GY), combined with three levels of irrigation regimes based on different crop evapotranspiration (ETc) replacements, including a 25% ETc, 50% ETc, and 100% ETc. The results indicated SH yielded the most fruits and accumulated the most total soluble solids (TSS) at harvest in 2020, however, it showed the lowest TSS in the second season. In 2020, SH and HQ showed higher concentrations in most of the anthocyanin derivatives compared to the VSPs. Similar comparisons were noticed in 2021 as well. SH and HQ also accumulated more flavonols in both years compared to other trellis systems. Overall, this study provides information on the efficacy of trellis systems on grapevine yield and berry flavonoid accumulation in a currently warming climate.

Teasing apart terroir: the influence of management style on native yeast communities within Oregon wineries and vineyards

Newer sequencing technologies have allowed for the addition of microbes to the story of terroir. The same environmental factors that influence the phenotypic expression of a crop also shape the composition of the microbial communities found on that crop. For fermented goods, such as wine, that microbial community ultimately influences the organoleptic properties of the final product that is delivered to customers. Recent studies have begun to study the biogeography of wine-associated microbes within different growing regions, finding that communities are distinct across landscapes. Despite this new knowledge, there are still many questions about what factors drive these differences. Our goal was to quantify differences in yeast communities due to management style between seven pairs of conventional and biodynamic vineyards (14 in total) throughout Oregon, USA. We wanted to answer the following questions: 1) are yeast communities distinct between biodynamic vineyards and conventional vineyards? 2) are these differences consistent across a large geographic region? 3) can differences in yeast communities be tied to differences in metabolite profiles of the bottled wine? To collect our data we took soil, bark, leaf, and grape samples from within each vineyard from five different vines of pinot noir. We also collected must and a 10º brix sample from each winery. Using these samples, we performed 18S amplicon sequencing to identify the yeast present. We then used metabolomics to characterize the organoleptic compounds present in the bottled wine from the blocks the year that we sampled. We are actively in the process of analysing our data from this study.

Climate ethnography and wine environmental futures

Globalisation and climate change have radically transformed world wine production upsetting the established order of wine ecologies. Ecological risks and the future of traditional agricultural systems are widely debated in anthropology, but very little is understood of the particular challenges posed by climate change to viticulture which is seen by many as the canary in the coalmine of global agriculture. Moreover, wine as a globalised embedded commodity provides a particularly telling example for the study of climate change having already attracted early scientific attention. Studies of climate change in viticulture have focused primarily on the production of systematic models of adaptation and vulnerability, while the human and cultural factors, which are key to adaptation and sustainable futures, are largely missing. Climate experts have been unanimous in recognising the urgent need for a better understanding of the complex dynamics that shape how climate change is experienced and responded to by human systems. Yet this call has not yet been addressed. Climate ethnography, coined by the anthropologist Susan Crate (2011), aims to bridge this growing disjuncture between climate science and everyday life through the exploration of the social meaning of climate change. It seeks to investigate the confrontation of its social salience in different locations and under different environmental guises (Goodman 2018: 340). By understanding how wine producers make sense of the world (and the environment) and act in it, it proposes to focus on the co-production of interdisciplinary knowledge by identifying and foreshadowing problems (Goodman 2018: 342; Goodman & Marshall 2018). It seeks to offer an original, transformative and contrasted perspective to climate change scenarios by investigating human agency -individual or collective- in all its social, political and cultural diversity. An anthropological approach founded on detailed ethnographies of wine production is ideally placed to address economic, social and cultural disruptions caused by the emergence of these new environmental challenges. Indeed, the community of experts in environmental change have recently called for research that will encompass the human dimension and for more broad-based, integrated through interdisciplinarity, useful knowledge (Castree & al 2014). My paper seeks to engage with climate ethnography and discuss what it brings to the study of wine environmental futures while exploring the limitations of the anthropological environmental approach.

Local adaptation tools to ensure the viticultural sustainability in a changing climate

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...