In vitro propagation of Italian cultivars of Vitis vinifera and evaluation of genetic stability by SSRs markers

An in vitro protocol has been carried out for an effective propagation of six cultivars of grapevine, 'Lambrusco salamino', 'Lambrusco di Sorbara', 'Lambrusco Marani', 'Trebbiano modenese', 'Ancellotta' and 'Malbo gentile'. Nodal segments from greenhouse growing vine-stocks were used as explants. Different medium compositions were tested and the explants could be initiated on MS and MS ½ media supplemented with 1.1 mg L-1 BA. Subsequent cultures were carried out by growing the shoots on MS with 1.1 or 0.55 mg L-1 BA; BA was shown to affect positively the shoot length when applied at the lowest concentration tested. MS media, supplemented with 0.5 or 1.0 mg L-1 IBA, with and without activated charcoal (AC), were used for adventitious root induction. Shoots of 'Lambrusco salamino', 'Malbo gentile' and 'Trebbiano modenese' rooted in all conditions with some qualitative differences. Rooting appeared to be greatly stimulated by 1 mg L-1 IBA plus AC in 'Lambrusco Marani', and without AC in 'Ancellotta'. In 'Lambrusco di Sorbara', a cultivar recalcitrant to rooting, we managed to stimulate the root formation on MS ½ supplemented with 1 mg L-1 IBA and deprived of AC. Genetic stability, evaluated at the third subculture, and analyses of nine microsatellite loci showed an unvaried genetic profile between micropropagated shoots and adult trees from which explants were taken.