The response of commercially managed, field grown, grapevines (Vitis vinifera L.) to a simulated future climate consisting of elevated CO2 in combination with elevated air temperature
To date, viticulture around the world has focused on increased temperature as the primary effect of climate change, largely ignoring the potential impact of elevated atmospheric carbon dioxide concentrations (eCO2). We have previously developed an open top chamber (OTC) system that used an active heating system to generate 2°C of climate warming in a mature vineyard, managed to current commercial practice. Those OTCs were subsequently augmented with a system to elevate CO2 around the grapevines, thereby providing the capacity to simulate warming and eCO2 simultaneously, simulating a future climate. Sixteen OTCs have been established, in a Shiraz vineyard, together with additional non-chamber controls. The OTCs were randomly assigned to four treatments, providing warming and eCO2 in a factorial experiment, which allowed the interaction between the two factors to be studied as well as their combined effect. The experimental system was fully operational prior to budburst in the 2013/14 growing season. As a C3 plant, and based on the very limited published data on grapevine responses to eCO2 we hypothesised that vine growth, fruit biomass and carbohydrate reserves would be greater under eCO2. Our previous OTC experiment demonstrated that all aspects of vine phenology were advanced under 2°C of warming, but that there was little effect on leaf physiology. Consequently, the focus of the new work was also on phenology, including the interaction between warming and eCO2. Vine growth, carbohydrate status, canopy physiology and nutrition were also examined.
Edwards, E.J., Unwin, D.J., Sommer, K.J., Downey, M.O. and Mollah, M. (2016). The response of commercially managed, field grown, grapevines (Vitis vinifera L.) to a simulated future climate consisting of elevated CO2 in combination with elevated air temperature. Acta Hortic. 1115, 103-110
climate change, phenology, photosynthesis, viticulture, water use efficiency