Effect of Explant's Size and Phytohormonal Composition of Nutritive Medium on Post-Vitification Recovery of Garlic Meristems

Abstract

Investigation of the effect of explants dimensions and composition of nutritive medium on morphometric parameters of devitrified garlic meristems will enable a significant optimizing of the cryopreservation techniques intended to establish a collection of its cultivars at low temperature bank. Apexes were subjected to dehydration with plant vitrification solution (1M sucrose + 2M glycerol + 2.5 M ethylene glycol based on Murashige-Skoog salt medium) for 120 min, placed into a polypropylene container and immersed into liquid nitrogen. Thawing was performed in a water bath at 40°C, washing of cryoprotectants was carried-out by a two-fold transfer into the medium with 0.3 M sucrose. It has been shown that the solution under study was non-toxic to garlic meristems and allowed the obtaining of a high level of viability. After cryopreservation by means of vitrification of garlic meristems of ‘Manuylivskyy’ spring variety the number of regenerated plants reached (56.3 ± 11.2)%, and ‘Duchess’ winter variety did (44.8 ± 3.7)%. For the cultivation of the cryopreserved garlic meristems as the phytohormone the kinetin is advisable to be used in concentration of 0.5 mg/l. It has been shown that after cryopreservation by vitrification the garlic meristems of 2–3 mm had the highest viability (60–70%). Larger meristems (3.5–4 mm) had a high regenerative potential but low viability (below 25%). In smaller meristems (1–1.5 mm) the viability rates were reduced (30–47%) as well as a regenerative potential. In the meristems of 0.5 mm a regenerative potential was absent.