CRYOPRESERVATION OF CHINESE OLD ROSES (ROSA CHINENSIS JACQ.) SHOOT TIPS BY VITRIFICATION

摘要

Nodal segments (5 mm in length) with apical buds excised from in vitro plantlets of Rosa chinensis Jacq. 'Old Blush' were precultured on a semi-solid Murashige and Skoog (MS) medium containing 0.3 M sucrose for 12 days at 4 degrees C in darkness. Shoot tips (1.5-2.5 mm) excised from the nodal segments were treated with loading solution for 20 min, and placed in the plant vitrification solution 2 for 60 min at 0 degrees C, finally rapidly plunged into liquid nitrogen for 1 h. After rapid warming in water-bath at 37 degrees C for 1 min, the shoot tips were washed with unloading solution for 10 min twice at 25 degrees C. The highest survival rate of shoot tips was 88.4% tested by 2,3,5-Triphenyl tetrazolium chloride staining. Shoot tips cryopreserved by the optimal protocol were plated on the semi-solid MS medium without plant growth regulators and transferred to darkness for 14 days prior to exposure to the light for the following 30 days. The regrowth rate was 43.3%. This vitrification procedure was successfully applied to 7 other varieties of Chinese old roses and the survival rate tested by 2,3,5-Triphenyl tetrazolium chloride staining ranged from 73.3% to 97.0%, the regrowth rate ranged from 26.7% to 45.6%. Our research demonstrates that the procedure is a promising technique for cryopreservation of shoot tips from in vitro-grown plantlets of Chinese old roses.