One hundred and sixty individual vines representative of the entire growing region for cv. Plavac Mali (Middle and Southern Dalmatia) were ampelographically analyzed in situ during a period of four years. High phenotypical variability was determined in the maturity period (35.6% “early maturity” vs. 11.9% “late maturity”), colouring (>50% of vines had bunches that were not coloured completely) and density of bunches, and degree of firmness of flesh and size of the berries. In a sample of 36 vines harvested in 2005 high variability was determined in: parameters of fertility, sugar content (range 66- 139°Oe), and the size parameters of bunches. The samples were tested for the presence of four viruses by ELISA test (Grapevine Fanleaf Virus (GFLV), Arabis Mosaic Virus (ArMV), Grapevine Leafroll associated Virus 1 and 3 (GLRaV-1 and GLRaV-3). 91% of all analyzed samples tested positive for GLRaV-3, while an infection with the ArMV (6%) was the least common. Only 5% of genotypes resulted as negative in virus testing. The results of the research point to a significant degree of intra cultivar genetical variability and the necessity of further individual clonal selection.

Vitis vinifera L.; cv. Plavac Mali; ampelography; clonal selection

Published by University of Zagreb, Faculty of Agriculture, Zagreb, CROATIA
Sponsored by Ministry Science and Education of the Republic of Croatia