SECTION THREE 



TRYPAN BLUE 



A nuclear stain for plant material 



Solutions required: 



A. Formol Acetic alcohol ( Telly esniczky) 

 Formaldehyde 40% 

 70% Alcohol 

 Glacial acetic acid . . 



B. Trypan blue 1% aqueous . . 



Ethylene glycol 



Absolute alcohol 

 Zinc sulphate 



C. Trypan blue 1% aqueous . . 

 Distilled water 

 Absolute alcohol 

 Cresol 

 HCl, concentrated . . 



D. Exactly the same as solution C but omit 

 the HCl. 



E. Absolute alcohol . . . . . . 95 ml. 



Cresol . . . . . . . . 5 ml. 



F. Naphthol yellow, saturated in equal volumes 

 of alcohol and ethylene glycol. 



G. Sodium thiocyanate 0-5% in equal volumes of 

 ethylene glycol and absolute alcohol. 



H. Ponceau 3R satd. in 80% alcohol i volume 

 80% alcohol . . . . . . I volume 



Technique: 



1. Fix epidermis or smears in solution A. 



2. Stain epidermis overnight in solution B or C. 



Note: Anther smears are stained in solution D for one half to 

 two hours. 



3. Differentiate in 50% alcohol (epidermis for about fifteen 

 minutes; smears for about five minutes), controlling by micro- 



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