Skip to main content
padlock icon - secure page this page is secure

Free Content Sucrose Treatment and Explant Water Content: Critical Factors to Consider in Development of Successful Cryopreservation Protocols for Shoot Tip Explants of the Tropical Species Dioscorea rotundata (Yam)

Download Article:
(PDF 529.5 kb)
A study was conducted to determine the optimum methods for conditioning explants to be used in the development of a simple protocol for long-term conservation of the germplasm of Dioscorea rotundata via cryopreservation. Shoot tips from cultures maintained in vitro were exposed to high concentrations of sucrose prior to silica gel-based dehydration and vitrification solution-based cryopreservation protocols. Explant water contents were determined, and ultrastructural studies were also carried out. Initially, culturing explants on medium supplemented with 0.3 M sucrose for 3-5 d considerably reduced tissue water content from about 12.2 g g−1 dry mass to between 4.8 and 5.5 g g−1 dry mass before cryoprotection with modified PVS2 (MPVS2) or silica gel dehydration. Ultrastructural studies indicated that cells had deposits of starch in plastids following sucrose treatments. Survival for D. rotundata shoot tips treated with MPVS2 vitrification solution, unloaded with 1.0 M sucrose medium and cooled to −70°C, was 16% for 15 min treatment and 44% for 40 min. After the 40 min MPVS2 treatment the TTZ test indicated 88% viability retention of explants cooled to −70°C, and 44% at −196°C. Plantlet development was obtained for −70°C-cooled shoot tips, whereas only callus development occurred from tissues exposed to liquid nitrogen. Explant regeneration was not obtained with air-dehydration techniques. It was concluded that vitrification-solution based cryopreservation presently offers the best option for conservation of this Dioscorea species.

16 References.

No Supplementary Data.
No Article Media
No Metrics


Document Type: Research Article

Publication date: May 1, 2009

More about this publication?
  • CryoLetters is a bimonthly international journal for low temperature sciences, including cryobiology, cryopreservation or vitrification of cells and tissues, chemical and physical aspects of freezing and drying, and studies involving ecology of cold environments, and cold adaptation

    The journal publishes original research reports, authoritative reviews, technical developments and commissioned book reviews of studies of the effects produced by low temperatures on a wide variety of scientific and technical processes, or those involving low temperature techniques in the investigation of physical, chemical, biological and ecological problems.

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more