Cryogenic Technologies for the Long-Term Storage of Citrus Germplasm

  • Anna De Carlo
  • Maurizio LambardiEmail author
  • Elif Aylin Ozudogru
Part of the Methods in Molecular Biology book series (MIMB, volume 710)


With its beautiful trees, Citrus species have long been valued by humanity. The tasteful fruits, extensively used for nutrition, are also good for health due to the high content in vitamins, minerals, and dietary fibers. Like majority of the woody fruit plants, Citrus germplasm is conserved mainly as field collections in clonal orchards. However, such a traditional approach presents several difficulties, among which are the high cost, manual labor, and extensive land required to maintain the collections, as well as the necessity of a careful protection of plants from diseases and extreme environmental conditions. As many species in the genus have seeds recalcitrant to desiccation, conservation in seed banks is also inadequate. On the other hand, cryopreservation, i.e., the storage of specimens at ultra-low temperatures (usually in liquid nitrogen, at −196°C) where reactions within the cells are minimized, presents a unique alternative for the safe storage of such germplasm. The present contribution outlines the cryopreservation techniques applied to seeds, zygotic and somatic embryos, embryogenic callus cultures of Citrus spp. and provides sample protocols to be used for Citrus conservation.

Key words

Citrus Cryopreservation Desiccation Embryogenic callus Embryos Encapsulation Nucellar cells Seeds Slow-cooling 



The procedure under Subheading 3.1 was optimized in the frame of the Project CRIOGERM, financially supported by the Ente Cassa di Risparmio di Firenze, which is gratefully acknowledged.


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Copyright information

© Humana Press 2011

Authors and Affiliations

  • Anna De Carlo
    • 1
  • Maurizio Lambardi
    • 1
    Email author
  • Elif Aylin Ozudogru
    • 2
  1. 1.IVALSA/Istituto per la Valorizzazione del Legno e delle Specie Arboree, CNRFirenzeItaly
  2. 2.Biology DepartmentGYTE, Gebze Institute of TechnologyGebzeTurkey

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