Osservazioni preliminari sull'attività vegeto-produttiva del "Sangiovese" innestato su tredici portinnesti nella zona di produzione del "Morellino di Scansano"

The main function attributed to rootstocks in grapevine-growing has so far been that of ensuring adequa1 te resistance against phylloxera and tolerance of other limiting soil and climate factors such as active lime¬stone, aridity, soil compaction, sali¬nity and so forth. In recent years, however, there has been increasing awareness that the rootstock also plays an important role as an inte-gral part of a complex mechanism which can influence the physiologi¬cal activity of the entire plant, with particular effect on vigor and other quantitative and qualitative aspects of production. Choice of rootstock thus represents one of the agronomic factors that can notably affect the economic results of a vineyard. Research on rootstocks was conducted at the Villa Acquaviva estate at Montemerano, in the Morellino di Scansano Doc area. The vineyard was set up in 1994 with 'Sangiovese' grapevines graf¬ted onto thirteen rootstocks (101-14, 1103P, UOR, 140Ru, 161-49, 41B, 420A, 775?, 779P, K5BB, S04, Gravesac). Vines were trained to espalier and pruned to horizontal single cordon. Results obtained in the first two years of observation showed some differences in vegetati¬ve and production behavior. In par¬ticular, 41B induced lower produc-tivity and elevated sugar levels while also maintaining good acidity levels, in contrast with virtually all the other rootstocks studied