TROPICAL FRUITS 



189 



growths, that give a rough, uninviting appearance. Often 

 the leaves are twisted and drawn out of shape. The warts 

 are at first yellowish, but as the disease ages they become 

 almost black, and finally crack open. 



Ammoniacal copper carbonate or Bordeaux mixture will 

 prevent this. 



Anthracnose, wither 

 tip {Colletotrichum glaeos- 

 porioides Penz.). — In 

 this disease the leaves 

 become spotted. The 

 spots are circular in out- 

 line, yellowish in color, 

 and bear small, dark 

 spots, the filaments and 

 spores of the causal 

 fungus. 



The disease also oc- 

 curs upon the fruit of 

 various citrus trees. 

 Rolfs noted its attack 

 upon the lemon, where it caused the fruit to fall pre- 

 maturely, and Hume reports that it may occur upon the 

 pomelo either before or after the fruit is picked. Here the 

 disease causes brownish spots which enlarge with age and 

 become dirty black in color. The fungus invades the in- 

 terior of the fruit as well as the rind. 



In all possible cases the diseased parts should be cut out, 

 care being taken to cut far enough back to get all injured 

 parts; also affected fruits should be removed and destroyed. 

 Spraying with Bordeaux mixture controls the disease upon 

 the fruit. 



Fig. 82. — Orange leaves showing spots caused 

 by anthracnose. After Hume. 



