INFLUENCE OF ROOT TEMPERATURE, ROOT STOCK AND FERTILIZATION ON THE COMPOSITION OF CABERNET SAUVIGNON GRAPEVINES

Two-year-old Cabernet Sauvignon grapevines on own-roots and on AxR # 1 (Ganzin 1) rootstock were grown at low (12°C) and high (25°C) root temperatures in combination with two fertilizer treatments on vines (0 and 2.4, 1.2 and 1.2 grams of N,P,K respectively, per 20 liter pot) in a greenhouse for a period of 15 weeks.
The dormant vines were pruned to two 10-node canes just prior to initiation of temperature and fertilizer treatments.
Air temperatures ranged between 15°C at night to 30°C during the day, and were the same for all treatments.

The levels of arginine, NO₃ and total N in roots was greater at low root temperature than at high root temperature.
High root temperature, however, increased the concentration of total N in leaf blades and NO₃ in blades and petioles of own-rooted vines compared to low root temperature.
Fertilization increased the concentration of nitrogenous substances in leaves and roots of all vines.
The levels of K, Ca, and Mg in leaf blades, petioles and roots were generally higher at 25°C than at 12°C root temperature.
The level of K was higher in leaves and roots of vines on own-roots than vines on AxR; however, the Ca and Mg content of these tissues did not show any consistant trends between AxR and own-rooted vines.

X African Symposium on Horticultural Crops

A. Zelleke, W.M. Kliewer

https://doi.org/10.17660/ActaHortic.1985.158.31