IN VITRO PROPAGATION OF WILD EUROPEAN PLUM (PRUNUS ×DOMESTICA L.), A RARE AND ENDANGERED SPECIES

Abstract

Wild European plum (Prunus xdomestica L.) is a rare and endangered species in China. To conserve this germplasm, a protocol for in vitro propagation of this species was developed. Nodal segments were used as the explants in our study. For the initiation of culture, B5 medium was better than Murashige and Skoog (MS) medium, which showed rapid growth of axillary bud within 3 days. Shoot organogenesis could be induced from both 6-benzylaminopurine (BAP) with α-naphthalene acetic acid (NAA) and BAP with indole-3-butyric acid (IBA) in B5 medium, but the regeneration efficiency depended on the ratio and concentration used. The higher regeneration efficiency existed in BAP:NAA=3-5:1 and BAP:IBA=1-3:1, when BAP concentration was in 0.5-1.0 mg/L. Rooting efficiency could be greatly increased with the addition of 0.4 mg/L IBA and no callus was observed on shoots in rooting media. Rooted plantlets were successfully acclimatized and grown in different transplanting medium. Plantlets in sawdust show higher survival rate than in soil and in vermiculite. This new system proved to be a practical way for germplasm conservation and for further investigation of wild European plum.