Water supply of crop plants is the most essential physiological condition influencing quality and quantity performance of grain yield. In a 12-year experimental series of winter wheat agronomic trials run at the Nagygombos experimental site (Hungary) the effect of water availability has been studied. The location represents the typical average lowland conditions of the country, the annual precipitation of the experimental site belonging to the 550–600 mm belt of the Northern edges of the Great Hungarian Plain, while the average depth of groundwater varies between 2 to 3 metres. Crop years with various precipitation patterns have had different impacts on crop yield quality and quantity. Yield figures were in positive correlation with annual precipitation in general. Water availability had diverse influence on quality manifestation. Good water supply has often resulted in poorer grain quality, especially wet gluten and Hagberg values have been affected by that. Drought reduced the amount of yield in general, but contributed to a better quality manifestation in some of the crop years.
