Project Number: P04000146
Project title: Impact of climate change factors on physiological and vegetative growth parameters of young grafted grapevines
Project leaders: Theron, H and Hunter, J J
Institution: Cape Peninsula University of Technology Stellenbosch University. Department of Viticulture and Oenology
Team members
Hunter, J J
Strever, A E
Volschenk, N
Paulse, C
Marais, A
Project completed: 2019
EXECUTIVE SUMMARY
Objectives and rationale: The purpose of this study was 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. The study provides important information for making better-informed decisions regarding cultivar and rootstock choice, terroir selection, and adaptations to current cultivation practices. Although the study was executed with young grapevines, it presented a unique opportunity to understand the grapevine’s reaction during the early stages of growth, when it is most sensitive to climatic conditions.
Methods: Four glasshouse compartments at ARC Infruitec-Nietvoorbij, Stellenbosch, were prepared according to treatment criteria and used for the duration of this study. The effect of temperature, CO2 and soil water on the growth and functioning of young, grafted grapevines was measured under controlled conditions.
Key results: CO2 and water were dominant factors affecting grapevine physiology, while water supply primarily determined the vegetative growth response. The vine’s phenological stage also impacted the level of response to climate conditions. Water availability will be crucial if expected changes in climate are realised due to its vital effect on physiological activity and grapevine growth.
Conclusions: The study was successful in emphasising the importance of multi-variable research regarding the possible effects of a changing climate on grapevines. More such studies linking water availability with the combined effects of increased CO2 levels and temperature are imperative to expand scientific knowledge and understanding of the complex reaction of grapevines to future climate conditions. This will support decision-making at production level.
Recommendation to the industry / Key take-home message: Climate change is a reality and will affect the agricultural sector, including the wine industry. Based on climate prediction models, the agricultural sector should position itself in expectation of increased ambient CO2 and temperature levels. Results from this project indicate that this scenario will enhance vegetative growth in grapevines, provided that adequate water is available. Grape and wine producers should be aware of this and will benefit by being open to investigating alternative production methods, cultivars, vineyard sites and wine styles.
P04000146 – Impact of climate change factors on young grafted grapevines – Final Report