الفهرس | Only 14 pages are availabe for public view |
Abstract In the present study, a reliable protocol for micropropagation of the two Egyptian grapevine (Vitis vinifera L.) cultivars ’Red Romy’ and ’Ghariby’ was developed using axillary bud explants. Nodal segments were cultured on MS-media (full strength MS or half strength MS) plus 3.0% sucrose and 0.7% agar with four concentrations of BA ,i.e. 0.0, 0.5, 1.0 or 2.0 mg/l for culture establishment. Half strength MS medium with 0.5 mg/l BA showed the highest efficiency in mean shoot length (11.65 and 8.37 cm) and mean number of shoots per explant (3.3 and 3.6) for cultivars ’Red Romy’ and ’Ghاariby’, respectively. For multiplication, shoots developed from the establishment stage were divided into sections (1.5 - 2 cm in length) and cultured on media comprised of {u00BD}MS basal medium plus 3.0% sucrose and 0.7% agar supplemented with different BA concentrations, i.e. 0.0, 0.5, 1.0 or 2 mg/l alone or in combination with different concentrations of IAA (0.1, 0.3 or 0.5 mg/l). The highest significant shoot length (13.32 and 9.11 cm) was found with growth regulator-free medium for ’Red Romy’ and ’Ghariby’, respectively. While, the highest number of shoots/explant (4.6 and 3.3) was recorded on {u00BD}MS medium with (2.0 mg/l BA + 0.3 mg/l IAA) and (0.5 mg/l BA + 0.1 mg/l IAA) for ’Red Romy’ and ’Ghariby’, respectively. Two cultivars (’Red Romy’ and ’Ghariby’) and a Chinese cultivar (’Cabernet Sauvignon’) were successfully cryopreserved by droplet vitrification. Axillary shoot tips were excised from two months old plantlets cultured on solidified {u00BD}MS medium with 0.5 mg/l BA, 3.0% sucrose and 0.7% agar (pH 5.8) at 25 {u25E6}C, under a 12 h light/12 h dark photoperiod with a light intensity of 40 oE m{u2013}2 s{u2013}1. For vitrification, excised shoot tips were precultured on {u00BD}MS solidified medium supplemented with 0.1 M sucrose for 3 days in darkness and then treated with a mixture of 2 M glycerol and 0.4 M sucrose (LS solution) for 20 min at 25 {u25E6}C. Shoot tips were then dehydrated with half-strength PVS2 vitrification solution (30% (w/v) glycerol, 15% (w/v) ethylene glycol, 15 % dimethylsulfoxide and 0.4 M sucrose in MS basal medium, for 30 min |