Limits of vitiviniculture: climatic challenges and opportunities of the Lào Cai (Vietnam) area

Abstract

With global warming, vitiviniculture has been spreading towards the poles. It also gains the tropics, probably because of the growth of economical powers such as Brazil and India and also thanks to significant agronomic progresses made since the middle of the 20^th century. Constant heat and humidity in some tropical areas limit the production of wine grapes, because the lack of cool nights and the development of cryptogamic diseases have negative impacts on the enological potential of grapes. These conditions are met in Lao Cai (North Vietnam) where two experimental vineyards have been planted in 2004, within the framework of a tripartite collaboration between the local authorities, the region Aquitaine (France) and the French Institute of the Vine and Wine (IFV). In these altitude vineyards (900 m and 1400 m asl) the winter is cold enough to offer only one production cycle from March to July. The summer monsoon favors the development of downy and powdery mildews, forcing the grape growers to anticipated harvest. The use of the Grapevine Flowering and Véraison model GFV to predict phenology in order to select adapted grape cultivars to these climatic conditions shows a difference of one month between observed and predicted dates. A spatial analysis using WordClim data shows that vitiviniculture expansion would be easier at lower height were constant heat would offer a better control of vegetative growth seasons.