Cryopreservation of Potato Shoot Tips

Potato is one of the most important staple crops in both developed and developing countries of the world. Potato genetic resources are a prerequisite for potato breeding in both conventional and genetic engineering programmes. Cryopreservation has long been considered an ideal means for the long-term conservation of plant genetic resources. This review provides comprehensive information on variously novel cryogenic techniques that have been developed since 1990. Factors affecting the success of cryopreservation of potato shoot tips are analyzed and discussed. Evidence of morphological and molecular analysis demonstrates that plants regenerated from cryopreserved shoot tips are genetically stable. Efficient elimination of potato viruses by cryotherapy of shoot tips provides an alternative method for virus elimination. Thus, the materials can be simultaneously prepared for virus elimination and long-term preservation. Routine application of cryopreservation of shoot tips for the long-term preservation of potato genetic resources has already started in Germany, Peru, Czech Republic and Korea. Speciesand cultivar-specificity has to be taken into account for much wider application when cryoprotocols are to be developed. Fundamental studies on mechanisms by which potato shoot tips withstand freezing in liquid nitrogen would help solve this problem. _____________________________________________________________________________________________________________