The viability of seeds is tested by:

Step-by-step solution

Viability of seeds can be known by two methods: (i) ability to germinate, (ii) testing their ability to respire. All viable seeds respire. This can be tested by immersing a section of seed containing the embryo in 0.1 % solution of triphenyl tetrazolium chloride. The viable embryo will turn pink due to conversion of colourless triphenyl tetrazolium chloride into insoluble coloured dye called triphenyl formazone due to reduction. Tetrazolium Chloride (TZ) test is also called as quick germination test. Related Theory