Vertical cordon training system enhances yield and delays ripening in cv. Maturana Blanca

Abstract

The growing interest in minority grape varieties is due to their potential for adaptation to global warming and their oenological capabilities. However, the cultivation of these varieties has often been limited due to their low economic efficiency. One such example is Maturana Blanca, a recently recovered and authorized minority grape variety in the DOCa Rioja region, known for its remarkable oenological potential but low productivity. This study aimed to increase the yield of Maturana Blanca by implementing the vertical cordon training system, which allowed for a higher number of buds per plant and an increased cluster count per vine. A comparative analysis was conducted between two training systems, head-trained (HT) and vertical cordon (VC), along with two irrigation regimes, rainfed and irrigation at 30 % of ET0. The results indicated that the training systems had a more significant impact on production and fruit composition compared to the irrigation treatment. Specifically, the VC system increased yield by ranging from 60% to 80% when compared to the HT system. Additionally, the higher productivity observed in the VC vines led to more optimal source-sink ratios, resulting in a tendency toward delayed ripening. This research provides valuable insights into viticultural practices to improve the productivity and quality of minority varieties such as Maturana Blanca and contributes to a broader understanding of sustainable viticulture and biodiversity preservation in the face of climate change. Moreover, our findings have significant implications to promote the cultivation and valorization of this minority grape variety adapted to semi-arid climates as an adaptation measure to counteract the challenges posed by global warming.