Cryopreservation of chayote (Sechium edule JACQ. SW.) zygotic embryos and shoot-tips from in vitro plantlets

Cryo Letters. 2002 Sep-Oct;23(5):299-308.

Abstract

This paper presents the development of cryopreservation protocols for zygotic embryos and apices of chayote (Sechium edule Jacq. Sw.), a tropical plant species with recalcitrant seeds. Zygotic embryos of two cultivars, Ccocro negro (CN) and Claudio (Cl) could withstand cryopreservation, with survival percentages of 10 and 30 %, after desiccation to 23 and 19 % moisture content (fresh weight basis), respectively. Apices sampled on in vitro plantlets of cultivars Cl, 13 and JM were successfully cryopreserved using a vitrification technique. Optimal conditions included the culture of mother-plants for 22 days on medium containing 0.3 M sucrose, culture of excised apices on the same medium for 1 day, loading of apices for 20 min with 2M glycerol + 0.4M glycerol, treatment with a series of diluted PVS2 solution (60 % PVS2 followed by 80 % PVS2 solution for 15 min (cultivar Cocoro Blanco [CB]) or 30 min (cultivars CN and Cl) at each concentration), rapid freezing and thawing, washing of shoot-tips with a 1.2 M sucrose solution, followed by recovery on media with progressively decreasing sucrose concentrations until the standard concentration of 0.1 M was reached. The highest survival percentages achieved ranged between 17 and 38 %, depending on the cultivar.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Clinical Protocols
  • Cryopreservation / methods*
  • Cryoprotective Agents / pharmacology
  • Cucurbitaceae / embryology*
  • Cucurbitaceae / growth & development
  • Culture Techniques / methods
  • Desiccation / methods
  • Plant Shoots / chemistry
  • Plant Shoots / drug effects
  • Plant Shoots / growth & development*
  • Seeds / chemistry
  • Seeds / drug effects
  • Seeds / growth & development*
  • Survival Rate
  • Time Factors
  • Water / analysis

Substances

  • Cryoprotective Agents
  • Water