Agronomic responses of grapevine ‘Chenin Blanc’ as a function of training systems and rootstocks

Abstract

The aim of this research was to study the influence of training system and rootstock on the yield, vigor and physiology of the ‘Chenin Blanc’ grapevine at São Francisco Valley, northeastern Brazil. An experiment was carried out on eight harvests, from 2013 to 2017, in Petrolina, in the state of Pernambuco. Grapevines were grown under two training systems, lyre and espalier, and five rootstocks: ‘IAC 572’, ‘IAC 313’, ‘IAC 766’, ‘Paulsen 1103’ and ‘SO4’, using a split-plot randomized block design, with training systems assigned to the main plot and the rootstock assigned to the subplot. Lyre favored an increase in the number of bunches, branches and leaf mass in the harvest of the first semester of the year, while in the second semester there were increases of 40 % in the number of bunches and 10 % in leaf mass. Lyre promoted more balanced vines, showing a better ratio between production and pruning weight (Ravaz index). The rootstocks ‘IAC 766’, ‘IAC 313’ and ‘IAC 572’ increased yield and bunch mass under both training systems, while ‘SO4’ reduced yield and vigor. The stomatal conductance and instantaneous efficiency of water use were not influenced by either the training system or the rootstock. Under tropical conditions in the São Francisco Valley, ‘Chenin Blanc’ grapevine may be grown under the lyre training system, preferably on the ‘IAC 766’ rootstock, to obtain high yields and balanced grapevines.