Influence of rootstock and trellis systems on the productivity of Sultana grapevines

Abstract

Sultana vines, either own-rooted or grafted to Dog Ridge or Ramsey rootstocks, were trained to 4 trellis systems: 0.3-m narrow T, 0.9-m wide T, arch cane, swing-arm. The swing-arm trellis generally gave the highest yields over the 9 years of the trial. Average annual yields were 19.5, 22.0, 15.6, and 26.2 kg/vine (1442 vines/ha), respectively, for the 4 trellis systems. Vines grafted to Ramsey rootstock had higher overall yields than own-rooted vines and vines grafted to Dog Ridge rootstock (24.0 v. 20.8 v. 17.8 kg/vine). The yield advantage conferred by Ramsey rootstock was greatest in years 1-3 of the trial. There was no significant trellis x rootstock interaction. Trellis effects on yield were primarily due to effects on bunch number, while rootstock had a greater effect on berry and bunch weight. Grafted vines were less fruitful than own-rooted vines. There was no significant difference in quality of fruit dried in a dehydrator, but when fruit was trellis-dried, quality was higher for the swing-arm than for the wide T-trellis, with the other trellises intermediate. Own-rooted vines produced better quality trellis-dried fruit than did vines grafted to Ramsey rootstock. The swing-arm trellis was not well suited to commercial production, but it produced good yields and had other desirable characteristics that are incorporated in some new trellis systems being developed in major dried vine fruit production areas in Australia.