بررسي تاثير سه نوع سيستم تربيت بر عملكرد و كيفيت محصول پنج رقم انگور

INFLUENCE OF THREE TRAINING SYSTEMS ON FRUIT YIELD AND QUALITY OF FIVE GRAPEVINE CULTIVARS

According to the vegetative and reproductive characteristics, grape is grown and trained on supporting systems for commercial production. The aim of training systems in grapevine culture is to maximize yield and fruit quality, facilitate garden operations and improve plant protection. The experiment was conducted in Horticultural Department Research Centre, Faculty of Agriculture, University of Tehran during years of 1998-2002, to investigate the effects of three training systems on yield, fruit quality and some vegetative characters of five grapevine cultivars. The systems used in this study were vertical shoot positioning (VSP), Y-trellis and sloping-T trellis and the cultivars were `Flame Seedlessʹ, `Dante Chinʹ, `Bidane Sefid Bidaneʹ `Ghermezʹ and `Shahroodiʹ. Length of bunch and sugar content of berries were affected by training systems but yield per vine and other measured characters were not affected. Sugar content of berries on Y-trellis and sloping-T training systems was higher than at VSP system. Although there was no significant difference between them. Length of bunch in sloping-T system was higher than other systems. There was also significant differences among the cultivars that was attributed to their genetic characters. Wind blowing resulted in some problems in sloping-T system such as breaking of shoots in early spring and rotating of vine canopy and the need of frequently tying cordons to cordon wire in this system. In general, according to present research Y-trellis system is recommended for five studied grapevine cultivars due to providing better light penetration into canopy. better distribution of shoots, decreasing fungal infection, producing high quality crop, easier pruning and harvesting and better access to bunches for different treatments.