Effect of training system and vine spacing on vine growth and productivity of Cv 'Barbera' in S. Colombano al Lambro (north Italy). First results

Shoot development and its effect on the density of a canopy notably influences the qualitative characteristics of the final product. The present preliminary study was aimed to analyse relations among vine space availability, training system, and vegetative expression. Barbera on 420A rootstock grown with two training systems in Northern Italy, and sis vine spacings were compared. Cordon de Royat compared to Guyot showed less variability as a consequence of increasing vine spacing. Although Cordon de Royat closer spaced vines were the most vigorous, they were significantly different only from the larger density in the shoot length, number of nodes/shoot, cane mass/ha, and cane size (weight per cm of cane). On Guyot the differences were more evident; high vine density induced dramatically inferior shoots length, number of nodes, and internodes length. These first results indicate a better stability in the vegetative expression of the Cordon de Royat to the change of plant density, which suggest a threshold value in the vine density beyond which the Guyot trained vines showed vegetative behaviour completely different from that of Cordon de Royat vine training.