Possible application of differential global positioning system (DGPS) to harvesting date and precision viticulture

Abstract

From 2004 to 2008, the maturity of grapevine (Vitis vinifera L.) was researched on the basis of sugar content and total titratable acidity at six locations with an undulating topography in three varieties: 'Chardonnay', 'Riesling' and 'Sauvignon'. All sampling points were geo-referenced simultaneously with differential global positioning system (DGPS) for creating sugar maps. The significant influence of the varying altitude above sea level (from 389 to 462 m) on the concentration of total sugar and the total titratable acidity of grapes were estimated during the ripeness of vine berry from July to September. The results of a five-year study proved that significant improvement of the grapes quality is possible by creating site-specific maps, which enable separate begging of harvest according to the different sea level.

Key words: Vineyard, sugar map, GIS, DGPS.