Stomatal features such as size and density are known to affect transpiration, even though stomata cover less than two percent of the area of a leaf. A study was undertaken to evaluate the differences in stomatal density among three grapevine cultivars in Albacete, (La Mancha, Spain) and its relation to grapevine transpiration. Work was conducted in two years of contrasting climatology. There was a drought in 2012 (rainfall during the fall-winter period was only 110 mm) while 2013 was a wet year (370 mm for the fall-winter period). The cultivar 'Tempranillo' was grown in a one-ha plot that has a weighing lysimeter in the middle for the direct measurement of transpiration of two mature plants. Cultivars 'Airén' and 'Macabeo' were studied in plots nearby where two irrigation treatments during bud break to veraison were imposed. In addition to stomatal density measured post-veraison on leaves of known areas, plant leaf area and transpiration were measured. The results suggest that stomatal density is related to transpiration in various ways. Cultivar 'Tempranillo' had less stomatal density than 'Airén' and 'Airén' less than 'Macabeo'.

ISHS Acta Horticulturae 1115: XXIX International Horticultural Congress on Horticulture: Sustaining Lives, Livelihoods and Landscapes (IHC2014): IV International Symposium on Tropical Wines and International Symposium on Grape and Wine Production in Diverse Regions.

Peer reviewed