East-west vineyard trellis system orientation improves water use efficiency and productivity of potted grapevines

Canopy architecture modulates light interception patterns affecting grapevine physiology and therefore water relations, productivity and ripening process. An experiment in potted red and white grapevines, ‘Bobal’ and ‘Verdejo’ respectively, was carried out during two seasons. The aim was to improve the whole vine water use efficiency (WUE) by means of orienting the vine row trellis system towards east-west direction instead of the more traditional north-south. Results show that east-west rows orientation significantly reduces transpiration by 13% in ‘Bobal’ and 5% in ‘Verdejo’ without compromising yield or clearly modifying the vegetative growth-productivity ratio. This is due to the lower amount of radiation intercepted by east-west hedgerows during the whole summer and the low photosynthetic efficiency of the north-south vines during the afternoon. These results show the relevance that the vineyard design and canopy architecture can play on the WUE and productivity. Nevertheless, more effort is needed in further seasons to improve our knowledge on canopy and vineyard management effects on vine WUE.