Sultana fruitfulness and yield as influenced by season, rootstock and trellis type

Abstract

Field-grown vines (Vitis vinifera L. cv. Sultana) were examined for their fruitfulness and yield performance over four growing seasons. Vines were either grafted to Ramsey rootstock (Vitis champini) or were grown on their own roots. Four commercially applied trellising systems were investigated, namely, a T-trellis, a Shaw trellis with a double cordon, a Shaw trellis with a single cordon and a Shaw swing-arm trellis. Fruiting potential was assessed shortly after budburst using the Merbein bunch count method. Bunches on vines that had been counted in springtime were again counted at harvest, and vine yield recorded. During the four years of the experiment fruitfulness was strongly influenced by growing season. Fruitfulness per node along the cane followed a well-established trend. Bud fruitfulness was close to zero in basal nodes but increased steeply thereafter reaching a maximum between nodes 8 and 10. Fruitfulness then decreased steadily. Grafted vines were always less fruitful than own-rooted vines, and this difference was amplified for all trellis designs in years when fruitfulness was low. At the time of pruning, more canes were retained on grafted than own-rooted vines in accordance with the greater vigour of grafted vines. This pruning strategy resulted in a larger number of bunches on grafted relative to ungrafted vines. Abbreviations and definitionsFruitfulness the proportion of primary buds that contain inflorescence primordia, estimated here after budburst; MBC Merbein bunch count

Reproductive performance of Cabernet Sauvignon and Merlot (Vitis vinifera L.) is affected when grafted to rootstocks

“…The difference in fruitfulness for scions on Ramsey between the study of Sommer et al. () and the present study may be partly due to the different vigour potentials of the scion—high for Sultana, moderate for Cabernet Sauvignon and low for Merlot (Dry ). Although vegetative growth (as measured by pruning mass and cane number) was higher on Ramsey than the ungrafted for both scion cultivars, this was not to the extent whereby higher shoot vigour or denser canopies were observed as described in Sommer et al.…”

“…Although vegetative growth (as measured by pruning mass and cane number) was higher on Ramsey than the ungrafted for both scion cultivars, this was not to the extent whereby higher shoot vigour or denser canopies were observed as described in Sommer et al. (). Conversely, a reduced fruitfulness was observed when both cultivars were grafted to 5C Teleki.…”

“…Fruitfulness for Ramsey has also been described as poor when compared to that of Sultana on own roots due to a higher vegetative growth of Sultana grafted to Ramsey (Sommer et al. ). In the present study, both Merlot and Cabernet Sauvignon on Ramsey and 1103 Paulsen had a higher fruitfulness than that of ungrafted vines, while Cabernet Sauvignon grafted to Schwarzmann had a significantly higher fruitfulness than this cultivar grafted to all other rootstocks, and this resulted in a significantly higher yield.…”

“…), climatic conditions (Buttrose , Dunn and Martin , Sommer et al. , ), excessive vigour or shading (Dry , Collins et al. ) and choice of rootstock through an effect on scion vigour (Candolfi‐Vasconcelos and Castagnoli , Cirami , Whiting , Dry , Candolfi‐Vasconcelos et al.…”

Monitoring salt stress in grapevines: are measures of plant trait variability useful?

“…These trends in shoot growth are consistent with previous studies (Walker et al 1981;Prior, Grieve & Cullis 1992b;Shani et al 1993;Fisarakis, Chartzoulakis & Stavrakas 2001) and may reflect a reduced growth rate resulting from a decrease in photosynthesis. Fitness reduction resulting from salt stress has previously been attributed to shade effects (Sommer, Islam & Clingeleffer 2001). Increased vigour in low salt stress zones compared with high zones may lead to greater competition for light within the canopy, forcing shoots to grow longer to reach sunlight.…”