Comparison between three different trellis systems in a steep vineyard of Piedmont (North West Italy).

In a very steep vineyard of Piedmont, long cane pruned vines trained to central curtain or lyre system were compared to vines trained on the traditional vertical trellis, and pruned according to a modified Guyot system (with a arched cane). The aim of the work was to reduce cultivation costs and improve, or at least not worsen, winegrape quality. The trial was carried out at Albugnano (AT) in an experimental vineyard (cv 'Malvasia di Schierano') in which the rows follow more or less the contour lines. The assessed parameters were: shoot number and development, total leaf area, stem water potential, light absorbance, ripening evolution and, at harvest, yield quantity and quality. From a qualitative point of view both lyre and vertical trellis seem to indicate better results than the central curtain, which had a higher yield. In particular musts from vines trained to lyre showed a tendency of higher accumulation of glycoside aromatic compounds. Nevertheles, the traditional vertical trellis confirms to be a system that allows a production of good quality, in the local conditions. It is also very important to remember that this system is less complicated and less costly to establish than the lyre system. In this steep slope, with rows following the contour lines, the establishment costs of lyre were high; as a consequence the yearly amortization costs were 30% higher than with the traditional system.