Short communication. Forage and nutritive value of the pruning residues (leaves plus summer lateral shoots) of four grapevine (Vitis vinifera L.) cultivars at grape harvest and two post-harvest dates

Abstract

The annual pruning of vineyards produces shoot and leaf residues that have traditionally been fed to sheep and goats. The aim of this work was to determine the forage and nutritive values of grapevine (Vitis vinifera L.) leaves plus summer lateral shoots at grape harvest and two post-harvest dates. The study cultivars were Cabernet Sauvignon, Merlot, Sauvignon Blanc and Sémillon, all grafted onto 5BB rootstocks. The leaves and summer lateral shoots were removed at the same time from each cultivar at three dates: grape harvest, 15 days post-harvest, and 30 days postharvest. No significant differences were seen between the cultivars in terms of their mean crude protein (CP) (45.44-46.33 g/kg), crude fibre (CF) (37.12-37.50%), neutral detergent fibre (NDF) (324.63-324.87 g/kg), acid detergent fibre (ADF) (247.44-249.44 g/kg), potassium (2.11-2.14 g/kg), calcium (3.85-3.95 g/kg) or iron (0.037-0.038 g/kg) contents at any of the three sampling dates. The highest fresh matter (1,765.33 kg/ha) and dry matter (DM) yields (610.67 kg/ha) were obtained from Sauvignon Blanc. The fresh matter yield, DM yield, CP, CF, NDF and ADF contents on the different sampling dates all differed significantly. The maximum fresh matter yield (1,925.33 kg/ha), DM yield (634.67 kg/ha) and CP content (61.67 g/kg) were recorded at grape harvest. The potassium, calcium and iron contents ranged from 2.11-2.15, 3.86-3.92 and 0.036-0.038 g/kg respectively at all stages. The leaves plus summer lateral shoots of Cabernet Sauvignon, Merlot, Sauvignon Blanc and Sémillon grapevine cultivars can be beneficially fed to sheep, goats and cattle in some viticultural regions of Turkey and other parts of the world.