Cryopreservation of Raspberry Cultivars: Testing Techniques for Long-Term Storage of Kazakhstan's Plant Germplasm

Authors: KOVALCHUK, IRINA - Almaty; TURDIEV, TIMUR - Almaty; KUSHNARENKO, SVETLANA - Almaty; RAKHIMBAEV, IZBASAR - Almaty; Reed, Barbara

Submitted to: Asian and Australasian Journal of Plant Science and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/2/2010
Publication Date: 7/10/2010
Citation: Kovalchuk, I., Turdiev, T., Kushnarenko, S., Rakhimbaev, I., Reed, B.M. 2010. Cryopreservation of Raspberry Cultivars: Testing Techniques for Long-Term Storage of Kazakhstan's Plant Germplasm. Asian and Australasian Journal of Plant Science and Biotechnology. 4:1-4.

Interpretive Summary: The genetic resources of vegetatively propagated plants are usually maintained in field genebanks. Tissue culture methods play an important role as backup collections for these irreplaceable plants. Medium-term backups can be held as shoot cultures in cold storage for several years, but also remain at risk of loss. In order to provide long-term storage of raspberry genetic resources, cultures of raspberries held in the Kazakhstan national germplasm collection were tested for cryopreservation in liquid nitrogen (-320°F). Three techniques were tested. Cold acclimation (CA) can be used to improve regrowth following cryopreservation, so the optimum duration in cold temperatures needed to produce cold tolerant plants was determined for two cultivars. Three weeks of CA was optimal for both types of raspberry. Regrowth of shoots following liquid nitrogen exposure was 59-82% with only one of the techniques. The other two techniques produced less than 50% regrowth in both cultivars. Eleven raspberry types were cryopreserved with the successful technique and stored in liquid nitrogen. Initial results after short liquid nitrogen exposure showed 52-82% regrowth from nine of the eleven raspberries. Samples remaining in liquid nitrogen for long-term storage will be assessed later. This study indicates that cryopreservation is a reasonable technique for long-term storage of Kazakhstan’s raspberry germplasm.

Technical Abstract: The genetic resources of vegetatively propagated plants are usually maintained in field genebanks. In vitro methods play an important role as backup collections for these irreplaceable plants. Medium-term backups can be held as in vitro cultures in cold storage for several years, but also remain at risk of loss. In order to provide long-term storage of raspberry genetic resources, in vitro cultures of raspberry cultivars and selections held in the Kazakhstan national germplasm collection were tested for cryopreservation in liquid nitrogen. Three techniques were tested, two with PVS2 vitrification and one with encapsulation dehydration. Cold acclimation (CA) can be used to improve regrowth following cryopreservation, so the optimum CA duration was determined for two cultivars. Three weeks of CA was optimal for the best regrowth of raspberry ‘Druzhnaya’ while 3 to 5 weeks were best for ‘Anar’. Three months of CA did not improve regrowth for ‘Anar’. Regrowth following liquid nitrogen exposure was best with the 0.3 M sucrose pretreatment and the PVS2 vitrification technique. Cryopreservation with the other two techniques produced significantly less regrowth in both cultivars. Cultivars and selections Anar, Babiye Leto, Druzhnaya, Kerzhach, Kokinskaya, K-10-12, K-12-4, K-13-60, Latham, Osnovyanka, and Pathfinder were cryopreserved with the sucrose pretreatment and PVS2 vitrification technique and stored in liquid nitrogen dewars. Initial results after short liquid nitrogen exposure showed 52-82% regrowth from nine of the eleven raspberries. Samples remaining in liquid nitrogen for long-term storage will be assessed later. This study indicates that cryopreservation is a reasonable technique for long-term storage of raspberry germplasm