Girdling of shoots at flowering stage reduces shatter in grapevine cv. Malbec

PICCOLI P.; BERLI F.; CARRILLO N.; RODRIGUEZ J.; BOTTINI R.; BERLI F.

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020 vol. 26 p. 102 - 109

1322-7130

Background and Aims: Certain grapevine cultivars like Malbec are unstable in yield, due to poor fruit set or fruitlet abscission. The phenomenon is known as ?shatter? and this study aims to explore the potential of using the shoot girdling technique at flowering, to direct the carbohydrate partitioning towards inflorescences.Methods and Results: Fruitful Malbec shoots were girdled above the apical bunch, below the basal bunch, double girdled or not girdled (control) during 2016 and 2017. Most vegeta-tive variables were unaffected, but shoots widened and the leaf expansion improved in the fruit zone. Fruit set doubled in respect to control, ovary abortion was reduced, and fruit yield increased, mainly due to a greater number of small berries in the base and double girdled treatments. In addition, base girdling increased total soluble solids per berry, reducing phenol-ics concentrations in the normal size berries. Girdling effects were consistent during both sea-sons.Conclusions: Shoot girdling below the basal bunch proved to be effective in reducing shat-ter. The increase in carbohydrate supply available to the inflorescences during flowering was able to augment their weak sink strength relative to the perennial organs. Significance of the Study: Contribute to understanding the importance of the photoassimi-lates flow towards inflorescences in reducing shatter and increasing yield in Malbec vines.