Evaluation of berry resistance to detachment and compression of some new Vitis vinifera L. cultivars for table grapes

Abstract

Since quality requirements for table grapes are closely relatedto their mechanical characteristics, the aim ofthis work was the assessment of berry resistance to detachment from the pedicel and its resistance to compression at five new Vitis vinifera L. cultivars for table grapes: Gelu, Milcov, Napoca, Splendid and Transilvania. The determinations made on the mature berries consisted in the analysis of the normal pressing force and the deformation under its influence, as well as the force required for the detachment of berries from the pedicels, using a CETR UMT-2 tribometer. Grape berries with higher weight and volume and larger diameter (Transilvania cv.) incurred a higher mechanical deformation, while long berries (Gelu cv.) showed higher resistance to detachment from the pedicel probably due to a more pronounced development of vascular bundles, indicating a higher resistance of grapes to handling, packing, transport and storage.