Evaluation of Cover Crop Effects in a 'Pinot noir' Vineyard 1996-1997

Three different cover crop treatments were compared for their effects on vine growth, leaf gas exchange,\ud yield parameters and fruit composition. The treatments were: resident plants, an insectary plant mixture\ud and a grass cover. At veraison (August 21), photosynthesis rate was lowest for the vines with the grass\ud cover treatment, whereas transpiration rate tended to be higher. Water use efficiency was lowest for\ud vines with a grass cover on all three measurement days (post bloom, berries pea-sized, veraison). Shoot\ud growth, leaf area, yield and fruit composition were significantly lower for vines in the grass treatment\ud than in the resident plant treatment. Performance of vines with the insectary plant mixture was\ud intermediate between that of the two other treatments (resident plants and grass)