H2O2

Vinegar

Allowed for seed starilisation

Dear Prof. @Abdul ,

There are many ways of sterilizing using different biochemical and physical principles (osmosis, polarity, temperature, pH etc.), none of which is absolutely effective, therefore it's important to combine them and sterilize all the used material.

This is the protocol I use:

Seal the filter paper in a bag and autoclave it for 20' at 121°C reaching 300 kPa.

Work under laminar flow hood that has been sterilized with radiations and EtOH before use.

Shake the seeds for 5' to 10' in 400-1000 uL of a solution 12% (V/V) NaOCl + Triton X-100 in proportion 1000:1, then centrifuge, remove the solution using 10 uL tip on a 1000 uL one in order to avoid taking the seeds.

Then I wash them with dH2O five times before spreading them on the filter paper with the last washing water and let them dry before use.

Alternatively use a solution 70% (V/V) EtOH twice for 2' or 10% Ca(ClO)2 for up to 30'. The bigger the seed, the longer the time.

Also solutions of 0.015% (m/V) KMnO4 , 3% (V/V) H2O2 and acids such as acetic acid and sulphuric acid are used.

One can also reduce time and concentration to use different solvents in sequence.

The sequence NaOCl, KMnO4 and H2O2 with rinsing with dH2O in between and afterward seems to give best results for nuts and beans.

Be careful not to mix them because permanganate and hypochlorite react with each other.

Other options:

Surface sterilization with HgCl2 and fumigation with methyl bromide and propylene oxide are effective, but seldom used because of the danger and required equipment. Same goes with irradiation with UV and gamma rays.

Article Effect of surface sterilization, fumigation and gamma irradi...

Titanium dioxide (TiO2) has been proven to be effective, but it's expensive.

Article Efficiency of Titanium Dioxide on Mungbean Seed Sterile and ...

The procedure may vary with the legume crops, dosage, and duration of exposure. Sodium hypochlorite, Triton X-100, and Mercuric chloride are found to be effective as seed sterilization agents. Treatment with 0.25% Triton X-100 for one minute and sterilization with 1% NaOCl for one minute is effective.

For example, several chemical agents are used to sterilise seeds, but the most effective include mercuric chloride, calcium carbonate, sodium hypochlorite, and others. However, a mild detergent or bleach solution may be used as a low-cost alternative. However, employing ethanol is not advised since it destroys seeds more effectively than bleach and does not kill bacteria or fungal spores.

Dear Prof. Aswathi Raj K P mam, can you please tell me more about Triton X-100?

Abdul Awal Chowdhury Masud

Triton X-100 is a surfactant that can be used to sterilize legume seeds. Check out the publication of Jisha and Puthur, in which Triton X-100 is employed for seed sterilization.