Cryopreservation of germplasm is done at -196°C using liquid nitrogen. This is a technique used to preserve genetic material, such as seeds, eggs, embryos, or sperm, at extremely low temperatures to maintain their viability for future use. Here are some details about the process:

Why use cryopreservation?

Cryopreservation is used to preserve the genetic diversity of plant and animal species, particularly those that are rare, endangered, or difficult to propagate through traditional methods. It is also used in assisted reproductive technologies, such as in vitro fertilization (IVF) and embryo transfer, to improve the success rate of these procedures.

How does cryopreservation work?

Cryopreservation works by slowing down the metabolism of cells and tissues to prevent them from deteriorating over time. To do this, the sample is exposed to a cryoprotectant solution, which helps to prevent ice crystal formation that can damage cell membranes. The sample is then cooled gradually to -196°C using liquid nitrogen, which is a cryogenic fluid that can maintain these low temperatures for long periods of time.

What are the advantages of cryopreservation?

Cryopreservation has several advantages over other methods of germplasm preservation, including:

- Long-term storage: Germplasm can be stored for many years or even decades without losing viability.
- Cost-effective: Cryopreservation requires minimal space and equipment compared to other preservation methods, such as field gene banks or plant tissue culture.
- Safe: Cryopreservation eliminates the risk of contamination or genetic drift associated with other preservation methods.
- Efficient: Cryopreservation allows for the storage of large quantities of germplasm in a small space.

In conclusion, cryopreservation of germplasm is done at -196°C using liquid nitrogen, which is a technique used to preserve genetic material for future use. This method has several advantages over other preservation methods and is particularly useful for rare or endangered species.