TY - JOUR T1 - Effects of Excessive Potassium Levels On pH, Acidity and Color of Fresh and Stored Grape Juice JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 35 LP - 39 DO - 10.5344/ajev.1983.34.1.35 VL - 34 IS - 1 AU - J. R. MORRIS AU - C. A. SIMS AU - D. L. CAWTHON Y1 - 1983/01/01 UR - http://www.ajevonline.org/content/34/1/35.abstract N2 - Three excessive rates of potassium (K) were applied throughout the growing season to two-year-old containergrown Concord (Vitis labrusca L.) vines. Excessive K resulted in an increase in the K levels and a decrease in the magnesium (Mg) levels of leaves, petioles, canes, trunks and roots at fruit harvest and, to a lesser extent, during dormancy. Potassium levels in petioles correlated better with K and pH in fresh and stored juice than did the K levels in other plant parts. Excessive K levels in the juice were detrimental to fresh and stored juice pH and color quality. High juice pH levels, created by the excessive K fertilization, produced problems in color stability during storage ER -