Effects of Rootstock and Nitrogen Fertilization on the Growth and Yield of Chardonnay Grapevines in New York

Abstract

Two rootstocks and three nitrogen fertilizer rates were evaluated for their effects on growth, yield, and petiole nutrient concentrations of Chardonnay (<i>Vitis vinifera</i> L.) grapevines. Rootstock had a greater effect on scion growth than did differential N application (0, 39, or 84 kg N/ha/yr), even though increased N availability significantly increased petiole N concentrations in the second year of application. Cane pruning weights of vines grafted to Couderc 3309 (C-3309) rootstocks averaged 1.42 and 1.20 kg/vine in 1984 and 1985, respectively. Pruning weights of vines grafted to Elvira averaged 0.75 and 0.79 kg, respectively, in those years. Fruit yields were not proportional to vine size; yields averaged 4.55 and 4.45 kg per vine in 1984 and 1985, respectively, with vines grafted to C-3309 and 4.08 and 4.13 kg per vine, respectively, for vines grafted to Elvira. Increased N availability reduced yields with vines grafted to C-3309 and increased yields in one year with vines grafted to Elvira. The percentage of flowers that set fully developed berries in 1985 was greater for vines grafted to Elvira than for vines grafted to C-3309. Fruit set of non-fertilized vines grafted to C-3309 was greater than fruit set of vines that received 84 kg N/ha. In addition to effects on growth and fruit set, vines grafted to C-3309 were associated with greater shoot growth rates, greater petiole potassium concentrations, and denser canopies than were vines grafted to Elvira. Neither rootstock nor applied N affected the duration of vegetative growth.