Question

Before inoculation into the culture media in tissue culture, the explant is sterilised by _________________.

Answer 1

Tissue culture is a technique in which fragments or cells of tissue from a plant is transferred to an artificial environment in which they can continue to survive and function. Tissue culture begins with the selection of an explant. An explant is any plant part, tissue or organ that is grown or cultured in a sterile culture medium.

Sterilisation is done for explants to prevent any microbial contamination.

Explants are treated with antimicrobial chemicals such as chlorine water or 1% sodium/calcium hypochlorite solution.
This is known as surface sterilisation as it removes any microbes that might be superficially present on the explant. The reagents used are mild enough to prevent any damage to the cells of the explant.

The vessels, culture media and instruments are completely sterilised in autoclaves with pressurised steam of 120°C at 12-15lbs of pressure for 15-20 mins. Autoclaving is not done to sterilise the explant as the high heat would kill the cells of the explant.

Water boils at 100°C. Boiling the explant in water for 10 minutes will not only kill microbes but also the cells of the explant.

UV radiation is mostly used to sterilise inoculation chambers or entire rooms where tissue culture is performed. UV radiations cannot be used on the explant as these might destroy the DNA of the explant cells by inducing harmful mutations.