Plant Growth, Leaf Gas-Exchange, Fruit Yield and Quality as Affected by Green Covers 1995-1996

Three different green cover treatments were compared in their effect on leaf gas-exchange, vine growth,\ud yield and fruit composition. The treatments were: grass cover, resident plants, and an insectary plant\ud mixture. Photosynthesis, transpiration, and water use efficiency were lower for vines with a grass cover.\ud Leaf area and shoot growth did not show a response to green cover treatment. There were no treatment\ud responses in yield and yield components except for mean berry weights which were lower for vines with\ud a grass cover. There were no differences in must soluble solids or total sugar per vine. Titratable acidity\ud was higher for vines with a resident plant cover and pH was higher for vines with an insectary plant\ud cover. The results reflect, to some extent, the higher degree of root zone competition experienced by\ud vines with a grass cover