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METHODS IN PLANT HISTOLOGY 
5. Stain in light green in clove oil for 1 to 3 minutes. 
6. Wash in absolute alcohol, or in carbol turpentine. 
7. Clear in xylol and mount in balsam. 
The time factors will vary slightly with different material. If 
the light green overstains slightly it may not interfere much with the 
differentiation. Mycelium, spores, amoebae, and bacterioidal tissue 
stain red and the host tissues green. If tissues do not stain readily, 
mordant in a 1 per cent solution of potassium permanganate in water 
for 2 to 5 minutes, wash in water, pass through the alcohols to 85 per 
cent alcohol, and stain. The mordant does not keep. 
This combination has given good results with the following ma¬ 
terial: Plasmodiophora brassicae, legume tubercles , Albugo Candida , 
Phytophora infestans , Uromyces caryophyllinus, Puccinia graminis , 
and many others. 
