terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Time vs drought: leaf age rather than drought drives osmotic adjustment in V. vinifera cv. Pinot Noir

Time vs drought: leaf age rather than drought drives osmotic adjustment in V. vinifera cv. Pinot Noir

Abstract

Global warming and increased frequency and/or severity of drought events are among the most threatening consequences of climate change for agricultural crops. In response to drought, grapevine (as many other plants) exhibits osmotic adjustment through active accumulation of osmolytes which in turn shift the leaf turgor loss point (TLP) to more negative values, allowing to maintain stomata opened at lower water potentials1. We investigated the capacity of Pinot noir leaves to modulate their osmotic potential as a function of: (i) time (seasonal osmoregulation), (ii) growing temperatures, and (iii) drought events, to enhance comprehension of the resilience of grapevines in drought conditions. We performed trails under semi-controlled field conditions, and in two different greenhouse chambers (20/15 °C vs 25/20 °C day/night). For two consecutive vegetative seasons, grafted potted grapevines (Pinot noir/SO4) were subjected to two different water regimes for at least 30 days: well-watered (WW) and water deficit (WD). Via pressure-volume (PV) curves and osmometer measurements we derived the leaf osmotic adjustment capability and TLP, while monitoring the plant gas exchange and water potential. Surprisingly, lower water potentials in WD vines throughout the season and in all situations (field and greenhouse) did not trigger osmoregulation, changes in TLP nor a modification of the modulus of elasticity. PV curves provided clear evidence that both temperature and water availability do not stimulate active osmotic adjustment in Vitis vinifera cv. Pinot Noir. Conversely, there is a clear impact of seasonal osmoregulation throughout the growing season2, decreasing the osmotic potential at full turgor by an average of 0.46 MPa in 90 days. Lack of osmotic adjustment in response to drought observed in this cultivar suggests Vitis genotypes have a broad spectrum of responses to drought and the strategy adopted to cope with it is highly dependent on the cultivar under analysis.

Acknowledgements:

The work was financially supported by the Austrian Science Fund (FWF): I 4848 “PlasticGrape”.

References:

1)  Bartlett, M. K., Scoffoni, C., & Sack, L. (2012). The determinants of leaf turgor loss point and prediction of drought tolerance of species and biomes: a global metaanalysis. Ecology letters15(5), 393-405.

2)  Herrera, J. C., Calderan, A., Gambetta, G. A., Peterlunger, E., Forneck, A., Sivilotti, P., … & Hochberg, U. (2022). Stomatal responses in grapevine become increasingly more tolerant to low water potentials throughout the growing season. The Plant Journal109(4), 804-815.

DOI:

Publication date: October 3, 2023

Issue: ICGWS 2023

Type: Article

Authors

Elena Farolfi1*, Francesco Flagiello2, Federica De Berardinis1, Soma Laszlo Tarnay1, Jan Reščič3, Astrid Forneck1, Jose Carlos Herrera1

1University of Natural Resources and Life Sciences, Vienna, Department of Crop Sciences, Institute of Viticulture and Pomology, 3430 Tulln an der Donau, Austria
2University of Natural Resources and Life Sciences, Vienna, Department of Crop Sciences, Institute of agronomy, 3430 Tulln an der Donau, Austria
3University of Nova Gorica, School for Viticulture and Enology, Dvorec Lanthieri/Lanthieri Mansion Glavni trg 8, 5271 Vipava, Slovenia

Contact the author*

Keywords

grapevine, drought, osmotic adjustment, osmoregulation, turgor loss point

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Chemical profiling and sensory analysis of wines from resistant hybrid grape cultivars vs conventional wines

Recently, there has been a shift toward sustainable wine production, according to EU policy (F2F and Green Deal), to reduce pesticide usage, improve workplace health and safety, and prevent the impacts of climate change. These trends have gained the interest of consumers and winemakers. The cultivation of disease resistant hybrid grape cultivars (DRHGC), known as ‘PIWI’ grapes can help with these objectives [1]. This study aimed to profile white and red wines produced from DRHGC in South Tyrol (Italy). Wines produced from DRHGCs were compared with conventional wines produced by the same wineries. The measured parameters were residual sugars, organic acids, alcohol content, pigments and other phenolics by LC-QqQ/MS, colorimetric indexes (CIELab); and volatile profiles (HS-SPME-GCxGC-ToF/MS [2]).

Potential of new genetic resources to improve drought adaptation of grapevine rootstocks

Grapevines are grown mainly as grafts worldwide, but the rootstocks most commonly used were selected between the late 19th and early 20th centuries and are based on reduced genetic diversity[1]. In the context of climate change, it is indeed urgent to diversify the range of rootstocks with genotypes much more adapted to drier environments, than the existing ones[2]. The aim of this study was to evaluate the potential of new genetic resources for grapevine rootstock breeding programs. For this purpose, 12 American and Asian wild Vitis species (3 to 5 accessions per species = 50 accessions) were evaluated for their rooting ability and drought response.

Stomatal abundance in grapevine: developmental genes, genotypic variation, and physiology

Grapevine cultivation is threatened by the global warming, which combines high temperatures and reduced rainfall, impacting in wine quality and even plant survival. Breeding for varieties resilient to these challenges must address plant traits such as tolerance to supraoptimal temperatures and optimized water use efficiency while minimizing productivity and quality losses. Stomatal abundance (SA) determines the maximum leaf potential for transpiration and thus water loss and cooling. Since SA results from a developmental process during leaf emergence and growth, knowledge on the genetic control of this process would provide specific targets for modification.

Vineyard management practices to reduce sugar content on ‘Monastrell’ grapes

Climate change is resulting in more dry and hot summers, accelerating grape ripening and increasing berry sugars concentration. This results in wines with a higher alcohol content, which has a negative impact on wine quality, as well as, on consumer health. Agronomic practices that minimize these effects on berry composition and, consequently, on wine quality must be defined. In this work, different management practices have been assessed on rainfed ‘Monastrell’ grapevines in Jumilla (Murcia, Spain) from 2021 to 2023 vintages. Mulching, shading, application of kaolin and different types of pruning were evaluated, among others field adaptation practices.

Biotic and abiotic factors affecting physiological aspects underlying vegetative vigour in two commercial grapevine varieties

Grapevine vigour, defined as the propensity to assimilate, store and/or use non-structural sugars for allowing fast growth of shoots and producing large canopies[1], is crucial to optimize vineyard management. Recently, a model has been proposed for predicting the vigor of young grapevines through the measurement of the vegetative growth and physiological parameters, such as water status and gas exchange[2]. Our objectives were (1) to explore the influence of the association of two grapevine varieties (Tempranillo and Cabernet Sauvignon, grafted onto R110 rootstocks) with arbuscular mycorrhizal fungi (AMF) on the vegetative vigour of young plants; and (2) to assess the effect of environmental factors linked to climate change on the vegetative vigour of Cabernet Sauvignon.