Submitted to: In Vitro Cellular and Developmental Biology - Plants
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2005
Publication Date: 6/5/2005
Citation: Ellis, D.D., D.M. Skogerboe, C.G. Andre, B.C. Hellier, and G.M. Volk, 2005. Cryopreservation of 12 allium sativum (garlic) accessions: a comparison of plant vitrification solutions (pvs2) and pvs3. In Vitro Cellular and Developmental Biology - Plants. June 5-7, 2005, Baltimore, Maryland. p. 11-12. Meeting Abstract.
Interpretive Summary: Cryopreservation in liquid nitrogen is used to preserve plant tissue for 100’s of years. It is therefore of value for the preservation of valuable germplasm which cannot be stored by conventional means as seed. Any crop which is vegetatively (clonally) propagated, like garlic, falls into this category as reproduction by seed does not yield a true-to-type plant. In garlic this is further compounded by the fact that many garlic accessions do not produce seed and do not store well as bulbs. Yearly grow-outs of this garlic is required to maintain the clone. Cryopreserving garlic could save the crop if a disease, insect or some other stress destroyed the field crop in a particular year. Cryopreservation of garlic has been reported and two main methods appeared successful. To initiate a program for the cryopreservation of many garlic genotypes, we compared the two methods. Results from this study confirmed that there was genotype-specificity in the response to the method, with one method working on some genotypes and the other on other genotypes. The conclusion from these data are that for the large-scale cryopreservation of multiple garlic genotypes, it is recommended that both methods be used on all accessions simultaneously.
Technical Abstract: The USDA's National Plant Germplasm System (NPGS) maintains more than 200 Allium sativum (garlic) accessions at the Western Regional Plant Introduction Station in Pullman, WA. Many accessions must be grown out in the field annually since garlic plants do not produce seeds and bulbs are difficult to store for extended lengths of time. Shoot tips excised from garlic cloves can be successfully cryopreserved using either Plant Vitrification Solution 2 (PVS2; 15% DMSO, 15% ethylene glycol, 30% glycerol, 0.4 M sucrose) or Plant Vitrification Solution 3 (PVS3; 50% sucrose, 50% glycerol). We compared regrowth of shoot tips representing diverse garlic germplasm after exposure to either PVS2 or PVS3 during the cryopreservation procedure. At the National Center for Genetic Resources Preservation, we consider accessions successfully preserved if a minimum of 40% of explants exhibit regrowth after liquid nitrogen exposure and at least 60 viable shoot tips remain in long-term storage. Eleven of twelve diverse garlic accessions were successfully cryopreserved using either PVS2 or PVS3 as cryoprotectants. Seven genotypes had higher regrowth levels after exposure to PVS2, three genotypes had higher regrowth levels after exposure to PVS3, and one genotype performed well using either vitrification solution. This project is part of an ongoing project aimed at cryopreserving accessions of the NPGS garlic collection.