Albugo Candida 1 (BLISTER BLIGHT) 



A. Classification: 

 Division I. Thallophyta. 



Subdivision II. Fungi. 

 Class V. Phycomycetes. 

 Order. Peronosporales. 

 Family. Peronosporaceae. 

 Genus. Albugo. 

 Species. Candida. 



B. Habitat: 



This fungus is parasitic on plants belonging to the 

 mustard family (Cruciferae) . It causes the " blister- 

 blight," or " white rust/' on the leaves and stems 

 of the shepherd's purse (Capsella bursa-pastoris) 

 and often on the radish. 



C. Naked-eye Characters: 



1. Describe the appearance (color, shape, size, etc.) 

 of the blisters formed by this parasite on the host- 

 plant. What organs of the host are affected? 



2. Make drawings, natural size, showing all the 

 features observed. 



D. Microscopic Characters: 



1. Study cross-sections of the host-plant taken through 

 one of the blisters. 



2. What causes the blisters? In what tissue or tissues 

 of the host does the mycelium grow? 



E. Nutrition and Growth: 



1. In what form must carbon be supplied to this plant? 

 Why? 



2. In thin sections look for absorbing organs (haus- 

 toria) , branching from the mycelium and penetrating 



1 Cystopus -candidus (Pers.) Lev. 



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