Grapevine is an economically important fruit crop; in fact the growing areas account over 10 million hectares in the world. It is reported that the number of cultivars ranges between 5000 and 8000, many of them are endangered. To avoid genetic erosion it's necessary the rescue and preservation of the grapevine germplasm both in situ and ex situ, e.g. in collection fields or in vitro. Growth reduction of in vitro cultures is obtained by decreasing O2 rate or temperature and light quantity. Cryopreservation at -196°C in liquid nitrogen (LN) is an in vitro cheap, sure, and easy method of preservation that we have been used since 2000. This method stops cellular divisions and metabolic processes of vegetal material (cellular suspensions, calli, shoot tips, somatic embryos) without damages or changes for unlimited period. Vegetal materials containing much water, are susceptible to chilling injury and must be dehydrated. Cryopreservation methods used include vitrification and incapsulation-dehydration. The last technique uses sucrose as cryoprotector and air-flow or silicagel to dehydrate, while alginate beads protect during this step. Vitrification technique uses chemical cryoprotectans such as dimethylsulfoxide (DMSO), ethyleneglycol, propilenglycol at low temperature. Cryopreservation begins to be used to eliminate viroses. There is a great number of viral diseases and among them Rupestris Stem Pitting (RSP) that is caused by different viruses and reported from almost all grapevine growing regions of the world. This virus complex causes serious damages to the plant: infected individuals show less vigour and delayed bud opening, and many of them decline and die within a few years. Till now meristem culture and thermotherapy have been the most used methods to obtain healthy plants. Among purposes of this experimentation, that has already showed good results in preservation of somatic embryos, there is the possibility of employing the cryopreservation of shoot tips to obtain virus-free grapevine plants. To explain recovery there is the hypothesis that freezing in LN kills the cells with large vacuoles in the lower layers of the infected shoot tips, while only small cells with dense cytoplasm, which are located in the top layers of shoot tips can escape an invasion of the virus, and can survive freezing in LN.
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