GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 Impact of changing climatic factors on physiological and vegetative growth

Impact of changing climatic factors on physiological and vegetative growth

Abstract

Context and purpose of the study – scientific information on grapevine response to predicted levels of climate parameters is scarce and not sufficient to properly position the Wine Industry for the future. It is critical that the combined effects of increased temperature and CO2 on grapevines should be examined, without omitting the important link to soil water conditions. The purpose of this study is to quantify the effects of envisioned changes in climatic parameters on the functioning and growth of young grafted grapevines under controlled conditions, simulating expected future climate changes. Scientific knowledge of precisely how the newly-planted grapevine will react morphologically, anatomically and physiologically (at leaf, root and whole plant level) to the expected changes in important climatic parameters will enable producers to make better-informed decisions regarding terroir, cultivar and rootstock choices as well as the adaptation of current cultivation practices.

Material and methods – four glass house compartments were set up with combinations of the two main environmental factors, namely ambient temperature and CO2. Within each compartment, another treatment factor, water supply, was introduced. Young, grafted grapevines were established in pots in a randomized block design. Five growth cycles of 12 weeks each were monitored, with Shiraz as scion cultivar in three of them and Merlot in the other two. The rootstock used throughout was 101-14 Mgt. Vegetative and physiological growth parameters were measured throughout the growth cycles with critical sampling times at 4, 8 and 12 weeks after planting.

Results – a change in environmental growth conditions significantly affected physiological activity of the grapevine. Both increased CO2 levels and adequate water supply increased photosynthetic activity for all treatment combinations. Newly planted vines were photosynthetically more active and reacted more strongly to treatments than slightly older vines. The higher temperature treatment seemed to impair photosynthesis under comparable CO2 and H2O conditions, especially with regards to very young vines. The effect of temperature on vegetative growth was insignificant compared to the CO2 and H2O effects and only seemed to affect initial growth directly after planting. The availability of water was critical to root, shoot and leaf growth – higher CO2 levels further enhanced vegetative growth.
The results indicate that the importance and impact of the climatic variables and the vine reaction change during the growth season. The strong interactions found between weeks after planting, available water, ambient temperature and CO2 levels necessitate multi-variable research on the effect of changing climatic factors on the grapevine.

DOI:

Publication date: March 11, 2024

Issue: GiESCO 2019

Type: Poster

Authors

H. THERON 1,2*, C.G. VOLSCHENK 3, J.J. HUNTER 3

1 Cape Peninsula University of Technology (CPUT), Wellington, South Africa
2 University of Stellenbosch (US), Stellenbosch, South Africa
3 ARC Infruitec-Nietvoorbij, Stellenbosch, South Africa

Contact the author

Keywords

Climate change, Grapevine, CO2, Temperature; Water deficit, Growth, Physiology

Tags

GiESCO | GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Rootstock selection moderates the effect of rising temperatures through drought tolerance and modulation of stomatal conductance

Climate change is increasing crop evapotranspiration and reducing water availability, especially in the Mediterranean area.

Guyot or pergola for dehydration of Rondinella grape

Pergola veronese is the most important vine training system in Valpolicella area but Guyot in the last decades is diffusing. Rondinella is one of the three most important varieties

Zoning, environment, and landscape: historic and perspective

Dans une approche globale, nous proposons la définition suivante du zonage : “représentation cartographique associée à une sectorisation du territoire en zones unitaires homogènes à partir de facteurs discriminants établis sur la base d’indicateurs quantifiables et d’avis d’experts”. La première application de cette méthode a porté sur la caractérisation du terroir en liaison avec les aspects qualitatifs des vins. Il est également possible d’envisager d’appliquer cette démarche dans les stratégies environnementales et paysagères liées aux approches territoriales et aux pratiques viticoles. Cette méthode peut servir de base dans la mise en œuvre des outils financiers associés aux mesures environnementales (CTE, aides spécifiques).

Low-cost sensors as a support tool to monitor soil-plant heat exchanges in a Mediterranean vineyard

Mediterranean viticulture is increasingly exposed to more frequent extreme conditions such as heat waves. These extreme events co-occur with low soil water content, high air vapor pressure deficit and high solar radiant energy fluxes and result in leaf and berry sunburn, lower yield, and berry quality, which is a major constraint for the sustainability of the sector. Grape growers must find ways to proper and effectively manage heat waves and extreme canopy and berry temperatures. Irrigation to keep soil moisture levels and enable adequate plant turgor, and convective and evaporative cooling emerged as a key tool to overcome this major challenge. The effects of irrigation on soil and plant water status are easily quantifiable but the impact of irrigation on soil and canopy temperature and on heat convection from soil to cluster zone remain less characterized. Therefore, a more detailed quantification of vineyard heat fluxes is highly relevant to better understand and implement strategies to limit the effects of extreme weather events on grapevine leaf and berry physiology and vineyards performance. Low-cost sensor technologies emerge as an opportunity to improve monitoring and support decision making in viticulture. However, validation of low-cost sensors is mandatory for practical applicability. A two-year study was carried in a vineyard in Alentejo, south of Portugal, using low-cost thermal cameras (FLIR One, 80×60 pixels and FLIR C5, 160×120 pixels, 8-14 µm, FLIR systems, USA) and pocket thermohygrometers (Extech RHT30, EXTECH instruments, USA) to monitor grapevine and soil temperatures. Preliminary results show that low-cost cameras can detect severe water stress and support the evaluation of vertical canopy temperature variability, providing information on soil surface temperature. All these thermal parameters can be relevant for soil and crop management and be used in decision support systems.

A deep learning object detection approach for smart pest identification in vineyards

Flavescence dorée (FD) poses a significant threat to grapevine health, with the American grapevine leafhopper, Scaphoideus titanus, serving as the primary vector.