MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



13. Immerse in two changes of absolute alcohol for a total time 

 of two to three minutes. 



14. Wash in solution G for two to three minutes. 



15. Immerse in two changes of xylol for a total time of two to 

 three minutes. 



16. Mount in D.P.X. or Clearmount or Cristalite mountant. 



Results: 



Callose is stained sky blue to greenish blue; lignified cellulose 

 (in the xylem cells and in most cortical or phloem fibres and 

 sclereids) blue. Cellulose walls, nuclei, slime and cytoplasm, light 

 brown to greyish brown. 



Reference: Vernon, J. C. and Gifford, E. M. (1953), Stain Tech., 28, 49-53. 



LACMOID - MARTIUS YELLOW 

 For callose in pollen tubes 



Solution required: 



Lacmoid 0-01% .. .. .. 10 ml. 



Martins Yellow 0-01% .. .. lo ml. 



Add a few drops of diluted ammonia (o-i ml. 

 cone, ammonia with 10 ml. distilled water) until the 

 solution assumes an olive tint. 



Technique: 



1. Slender styles or ovaries are crushed between two slides while 

 still wet. Larger styles or ovaries should be cut by hand into longi- 

 tudinal sections, then crushed. 



2. Stain two to five minutes in the Lacmoid - Martins yellow 

 solution. 



3. Mount in the stain and examine under the microscope, using 

 a strong light. 



Results: 



Pollen tubes, blue. Background, light yellowish green. 



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