TY - JOUR T1 - Effect of Irrigation, Fruit Load, and Potassium Fertilization on Yield, Quality, and Petiole Analysis of Concord (<em>Vitis labrusca L.</em>) Grapes JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 145 LP - 148 DO - 10.5344/ajev.1982.33.3.145 VL - 33 IS - 3 AU - J. R. Morris AU - D. L. Cawthon Y1 - 1982/01/01 UR - http://www.ajevonline.org/content/33/3/145.abstract N2 - A 14-year old Concord vineyard which had received no potassium fertilization since establishment was fertilized with 0 or 450 kg/ha of K under two irrigation and two fruit load regimes. Supplemental irrigation from bloom to véraison increased yields and vine size. Juice soluble solids were reduced by irrigation in a year with near normal rainfall; but in a year of severe drought, soluble solids were improved by irrigation. Increased fruit loads reduced juice quality. Vines receiving K fertilization showed a response the first year of application through increased yeilds and vine size. Juice pH and K content were increased by K fertilization. ER -