Résumé
The influence of vine water status on the seasonal changes of fresh weight, dry matter and the levels of potassium and calcium in grape-berries on field vines of 'Grenache Noir' (Vitis vinifera L.), was studied over a two-year period. Two levels of water status, irrigated and non-irrigated, were investigated using a single level of total leaf surface – each primary shoot was confined to ten leaves, one grape bunch, and the secondary shoots were removed as they appeared. The mineral element contents were determined separately in different fruit compartments, i.e. the skin, flesh and seeds. Potassium and calcium accumulate independently of one another, but their seasonal change in the fruit and their final quantities in the berry depend principally on plant water status. The accumulation of potassium parallels the change in fruit fresh weight; approximately 50 % of the final content was accumulated pre-veraison and loading continued during berry ripening. This report shows that a small quantity of calcium may accumulate throughout fruit ripening phases in situations where water supply is not a limiting factor. These results imply that fruit xylem is functioning partially during ripening. Moreover, in both water status situations, the quantity of calcium in the skin increases during ripening, which suggests apoplastic and/or symplastic migration in the berry.