Impact of Pruning Severity on the Performance of Malbec Single‐High‐Wire Vineyards in a Hot and Arid Region

Background and Aim: The single‐high‐wire (SHW) system is a very productive trellis system suitable for the mechanization of cultural practices. It has been proposed as an adaptation strategy for mitigating the effects of global warming in warm and hot wine regions. The aim was to study the impact of different pruning severity treatments [16, 24 and 32 bud m −1 of productive cordon and simulated mechanical pruning (SMP)] on the performance of a Malbec SHW vineyard in a hot and arid region. Methods and Results: The vineyard performance was assessed by means of characterizing the canopy architecture, winter trunk reserves, yield, fruit and wine composition. The variation of the pruning severity affected the architecture of the shoots but did not affect the canopy total leaf area. Lower pruning severity levels increased the number of smaller shoots and decreased the proportion of the leaf area corresponding to secondary shoots. After 3 years of treatment, bud fruitfulness and winter wood reserves were not adversely affected by lowering pruning severity. In general, it was observed that the lower the pruning severity, the higher the yield. Indeed, the lowest pruning severity level (SMP) increased the number of smaller clusters with fewer and smaller berries. Moreover, we found that pruning severity did not affect the berry’s anthocyanin and volatile organic compound profiles. Additionally, reducing pruning severity slightly decreased soluble solid accumulation and alcohol content of wines without affecting colour and acidity. Conclusion: The cultivar Malbec trellised to the SHW system in a hot and arid region is able to self‐regulate between vegetative and reproductive growth, attaining maximum yield without forfeiting quality at low pruning severity levels such as it is imposed by mechanical box pruning. Significance of the Study: These findings support growing and managing Malbec on the SHW system with mechanized pruning in hot and arid regions.