Comparative studies on vine vigour and fruitfulness of wine varieties of grapes (Vitis vinifera L.) during summer pruning under Cumbum valley condition of Tamil Nadu

Field investigation was carried out during 2017-2018 in order to study the effect of summer pruning on vine vigour, fruitfulness and quality of wine varieties of grapes at Grapes Research Station, TNAU, Anaimalayanpatty, Theni, Tamil Nadu. The experiment was conducted in Randomized Block Design with three replications. The vines were trained on bower system with spacing of 3.0 m x 2.0 m and pruned during May. Among the ten wine grapes varieties (viz., Cabernet Sauvignon, Zinfandel, Shiraz, Merlot, Manjiri Medika, Muscat Hamburg, Chenin Blanc, Sauvignon Blanc, Symphony and Viognier) evaluated, the variety Manjiri Medika recorded the higher pruning mass (1.95 kg vine-1), shoot length (131.48 cm), number of canes vine-1 (49.75), cane diameter (20.63 mm), number of berries bunch-1 (102.45), individual bunch weight (549.88 g), yield (8.75 kg vine-1) with shorter internodal length (2.18 cm). The variety Muscat Hamburg had recorded earliness in bud sprouting (9.55 days) and highest individual berry weight (4.46 g). The number of internodes (13.35) and number of bunches vine-1 (46.77) were maximum in the variety Chenin Blanc.