This article will guide you about how to prepare cytokinins stock solution.
Take 50 mg of cytokinin in a clean dry test tube. Dissolve in 1-2 ml of IN NaOH. Slightly warm it and then add more distilled water volume to 100 ml. The final concentration of this stock will be 0.5 mg/ml.
Steps involved in medium preparation (MS 1 litre medium) are:
1. Take 1 litre capacity flask.
2. Add 50 ml of stock solution number 1.
3. Add 20 ml each of stock solutions number 2 and 3.
4. Add 10 ml each of stock solutions number 4 and 5.
5. Add 100 mg of myo inositol.
6. Add 30 g of sucrose.
7. Add distilled water to make volume to 900 ml.
8. Dissolve sucrose and myo inositol by continuous stirring/shaking the flask.
9. Add required concentration of growth regulator.
10. Adjust the pH of the medium to 5.8 with 1 N NaOH/HCl.
11. Add 7 g of agar (solidifying agent).
12. Make final volume to 1 litre with distilled water.
13. Boil the medium and stir while boiling to dissolve the agar.
14. Pour the boiled medium (15-20 ml) in the test tube/jars and plug with cotton plug/caps, respectively.
15. Autoclave the media at 121°C, at 15 lbs/square inch pressure for 20-25 minutes.
16. Store the media after autoclaving at room temperature for 2-3 days, before inoculations.
Precautions:
To avoid precipitation due to mixing of mono and divalent salts, prepare stock solutions (no. 1-5) as recommended; Store stock solutions in dark coloured bottles. Stock solutions should be properly labeled and stored in refrigerator. Never use precipitated stock solutions for media preparation. Adjust the pH of the media carefully otherwise media may not solidify after autoclaving. For inoculations, always use the media at least 3 days after autoclaving.