EFFECT OF PRUNING SYSTEMS ON LEAF PHYSIOLOGY AND GRAPEVINE PERFORMANCE.

Grapevine pruning is one of the most essential tools to ensure grapes quality and efficient yields of vineyards. Vine horticultural performance and leaf physiology of grapevine are influenced by viticultural practices. One of these practices is represented by pruning. The purpose of the present study was to evaluate the effect of pruning system on leaf physiology and vine performance. Currently, viticulture as a sector of agriculture is a priority sector for national and European Union policies that receive support and funding to ensure the competitiveness of wine-growing and the quality of wine products. In this context, the management of vineyard is essential to ensure the competitiveness of viticultural farms. The experiment was carry out on field conditions in a Stefanesti non-irrigated mature vineyard for two grapevine Vitis vinifera L. cultivars. The grapevines were represented by two Romanian table grape varieties: Vitis vinifera L. cv. Argessis and Vitis vinifera L. cv. Augusta. The training system used for grapevine was represented by Cazenave bilateral and cordon spur pruning with 14 buds per vine cordon. Effects of the pruning system on leaf physiology and vine performance were expressed using the following parameters: leaf area, photosynthesis rate (μmol CO2 m-2 s-1) in leaves, the relative water content (%) in leaves, respiration rate (μmol CO2 m-2 s-1), coefficient of relative and absolute fertility, relative and absolute productivity index. The coefficient of absolute fertility had a higher value for Augusta under the influence of cordon spur pruning and Argessis cultivar under the influence of Cazenave pruning. The highest value of photosynthesis rate was determined in Argessis for Cazenave pruning (7,643 μmol CO2 m-2 s-1). Grapevine canopy management by pruning is essential to select the best pruning method taking in consideration the local environment and grapevine cultivars. [ABSTRACT FROM AUTHOR]