Morphology and evaluation of bunch compactness in biotypes of cv. Bobal

Abstract

Bunch compactness is a relevant factor influencing the grape composition, which consequently affects wine quality. Clusters with higher compactness are more likely to present a heterogeneous ripening, where berries do not ripen evenly those inside the bunch remain less ripe due to the lack of sunlight. Furthermore, a high compactness leads to broken berries by pressure and reduces de air circulation in the bunch, creating favourable conditions for the development of cryptogamic diseases (Tello & Ibáñez, 2014).

The aim of this study was to determine how bunch compactness varies among 102 biotypes of Bobal variety from DO Utiel-Requena carried out during 5 seasons (2021-2025). For this purpose, physical parameters were measured (bunch and berry mass, bunch length and width among others). In addition, the variation in interannual compactness and the degree of consistency in the classification of biotypes were quantified. Consistent differences in bunch compactness were observed among biotypes. However, inconsistencies among compactness indexes were found and discussed.

The importance of characterizing bunch compactness lies in the potential of selecting Bobal biotypes with features that contribute to ensuring the grape and wine quality under a climate change scenario.

References

Tello, J., & Ibáñez, J. (2014). Evaluation of indexes for the quantitative and objective estimation of grapevine bunch compactness. Vitis, 53(1), 9-16. https://doi.org/10.5073/vitis.2014.53.9-16