260 DISEASES OF ECONOMIC PLANTS 



leaf tips by day, followed by night recovery. The wilting 

 becomes more pronounced on succeeding days until in the 

 third or fourth day the leaves wilt permanently, lose color, 



Fig. IIG. — Peanut leaf spot cercosporose. Original. 



dry, and soon fall. These stages may succeed each other 

 so rapidly as to appear almost simultaneous. The roots 

 appear normal ; but on the stem near the ground are found 

 shrunken, discolored areas in the bark, often extending 

 considerable of the way around the stem. Later the roots 

 may rot from secondary causes. 



