CHANGES IN YIELD AND QUALITY CARACTERISTICS OF VITIS VINIFERA L. CV. MUSCAT DE HAMBURG UNDER THE INFLUENCE OF GIBBERELIC ACID (GA3)
ROXANA COŢOVANU FILIMON 1, RĂZVAN V. FILIMON 1, LILIANA ROTARU 2 1. Research Development Station for Viticulture and Winemaking (SCDVV), 48 M. Sadoveanu Alley, Iaşi, Romania, e-mail: roxanacotovanu@yahoo.com; razvan_f80@yahoo.com
2. University of Agricultural Sciences and Veterinary Medicine (USAMV) “Ion Ionescu de la Brad”, 6 M. Sadoveanu Alley, Iaşi, Romania, e-mail: lirotaru@uaiasi.ro
The aim of the work was to determine the optimal dose of gibberelic acid (GA3) to be applied to achieve a higher yield and a harmonization of quality features at the grapevine cultivar for table grapes Muscat de Hamburg grown in Iasi vineyard, NE of Romania, in two years of harvest. Treatments were performed by spraying the inflorescences with 25 ppm, 50 ppm and 100 ppm GA3. The optimal dose of GA3 applied was 25 ppm, resulting in a higher yield and quality of grapes. Lower GA3 doses resulted in an equilibrated sugars/acid ratio, a higher accumulation of anthocyanins and phenolic compounds in berries, improving the commercial aspect of grapes by increasing color intensity and uniformity. The treatment led to an increase in production of over 18% and to a percentage of marketed production up to 74%. This variety develope a tolerance at high concentrations of GA3. The foliar photosynthetic activity was more intense causing an increasing intracellularly CO2 concentration.
