关键词: 香蕉, 茎尖, 超低温保存, 玻璃化法

Abstract: Shoot tips excised from healthy in vitro plants of three Banana cultivars were successfully cryopreserved with the vitrification technique. A suitable procedure was established as follows: 3 - 4 weeks after subculture, shoot tip s about 2 - 3 cm in length were precultured for 2 days onMS medium supplemented with
0.4 mol/L sucrose. Dissected shoot apices about 1.0 - 1.5 mm in length with one or two leaf primordium were loaded with a mixture of 2 mol/L glycerol plus 0.4 mol/L sucrose for 20 - 30 min at room temperature. These excised shoot tips were sufficiently dehydrated in a highly concentrated plant vitrification solution for 40 min at 0℃. And then plunged directly into liquid nitrogen and conserved for at least 1 h. After rapid thawing in water at 40℃ for 90 s, the tips were rinsed with 1.2 mol/L sucrose solution for 20 min at room temperature and then plated on MS medium supplemented with 0.5 mg/L 6-BA. The cryopreserved materials were cultured in darkness for one week so that they could grow quickly. Successfully cryopreserved shoot tips resumed growth
within 10 days of plating and developed shootswithin 1 month without intermediary callus formation. This simple protocol was successfully applied to the three cultivars belonging to two genomic group s of banana. The
survival rate of shoot tips was 75.9% , 40.0% , 69.6% , and regrowth rate reached 63.4% , 35.0% , 63.4% respectively. Almost all the shoot tips formed roots and were successfully transferred to soil in pots. The plantlets could normally root and survive after transplantation.

Key words: Banana, Shoot-tip, Cryopreservation, Vitrification