Cryopreservation

The preservation of cells, tissues, or germplasm by cooling them to very low sub-zero temperatures, usually –196°C, to stop all biological activity is called cryopreservation.

• Provides long-term, virtually unlimited storage of valuable genetic material
• Protects endangered plant and animal germplasm from extinction
• Supports ex-situ conservation strategies alongside seed banks and botanical gardens
• Preserves material for future breeding, research, and biotechnology applications

Before freezing, biological material must be treated with a cryoprotectant to prevent ice-crystal damage to cell membranes and organelles.

Selection of Plant Material (e.g., shoot tip, embryo)

↓

Treatment with Cryoprotectant (Glycerol / DMSO)

↓

Slow cooling to approx. −38°C 

↓

Transfer & Storage in Liquid Nitrogen (−196°C)

↓

Controlled thawing when required

↓

Reculturing / Regeneration of Plant

Cryopreservation has been successfully applied to preserve germplasm of the following species:

• Acer pseudoplatanus (Sycamore maple)
• Atropa belladonna (Deadly nightshade – medicinal plant)
• Capsicum annuum (Chilli/Pepper)
• Daucus carota (Carrot)
• Nicotiana tabacum (Tobacco)
• Oryza sativa (Rice)
• Arachis hypogaea (Groundnut)
• Lycopersicon esculentum (Tomato)

• Cryopreservation = storage at −196°C using liquid nitrogen
• Cryoprotectants (glycerol, DMSO) prevent ice-crystal cell damage
• Process order: Select → Treat → Cool (−38 °C) → Store (−196 °C) → Thaw → Regenerate
• Enables near-indefinite storage of plant/animal germplasm
• Successfully used in species like rice, tomato, tobacco, carrot, groundnut
• Distinct from seed banking and botanical gardens in method and scope