%0 Journal Article %A J. R. Morris %A S. E. Spayd %A D. L. Cawthon %T Effects of Irrigation, Pruning Severity and Nitrogen Levels on Yield and Juice Quality of Concord Grapes %D 1983 %R 10.5344/ajev.1983.34.4.229 %J American Journal of Enology and Viticulture %P 229-233 %V 34 %N 4 %X Concord (Vitis labrusca L.) grape response to supplemental irrigation, pruning severity, and nitrogen level was studied in a factorial experiment for four years. Supplemental irrigation increased yields and was beneficial in attaining acceptable quality levels and maintaining vine size when vines were less severely pruned. Balance-pruning to a 60+10 severity increased yields for the first two years, after which the 60+10 severity was similar in yields to the 30+10 severity. This adjustment in yield was due to the reductions in node fruitfulness and vine size by the 60+10 pruning severity. Nitrogen fertilization, at the levels used, had little influence on yields or vine size, but tended to increase percent soluble solids and pH, and to reduce titratable acidity. Additional nitrogen fertilization may be necessary to mature fruit on vines receiving supplemental irrigation. Juice quality as indicated by percent soluble solids and color tended to be related to yields, with higher yields resulting in lower quality. %U https://www.ajevonline.org/content/ajev/34/4/229.full.pdf