PRELIMINARY RESULTS OF TRIALS TO IMPROVE FUNGAL RESISTANCE IN PORTUGUESE VITIS VINIFERA CULTIVARS USING CLASSICAL BREEDING APPROACHES

In order to increase its natural resistance to downy mildew and powdery mildew infections, controlled crosses were made in 2001 and 2002, between the Portuguese Vitis vinifera red wine cultivars, ‘Aragones’, ‘Touriga National’ and ‘Vinhao’, and the resistant cultivars, ‘Regent’, ‘Gm 8331-1’ and ‘Gm 8331-2’. Until now, 793 hybrid seeds were obtained from the different crosses performed. The average seed germination rates were of 60% and the germinated plants are now in observation. The tests for fungus resistance were initiated and it was observed that 21 plants from the first 173 initial candidates presented resistance. Resistance evaluation is being performed either by classic methodologies of plant contamination using fungus contaminated foliar dishes or by the evaluation of “resveratrol” production. Both techniques produced satisfactory results. HPTLC techniques were tested for quantification of malvidin-3, 5-diglucoside on red wines.