226 DISEASES OF TROPICAL PLANTS OH. 



weeks. Bordeaux mixture is not successful in com- 

 bating this disease. 



Bacterial Wilt. The bacterial wilt (Bacillus solan- 

 acearum, Smith), which is so destructive on potatoes, 

 tomatoes, and egg - plants, also attacks the peppers 

 (pp. 210, 216). 



Fusarium Wilt. This disease is very similar to, and 

 probably the same as the disease of the same name 

 which attacks the tomatoes (page 212). 



Leaf Spot. This disease, which is due to Cercospora 

 sp., is very common on the pepper throughout 

 tropical and subtropical America. Although it 

 reduces the vitality of the plants, it is not destructive. 



Leaf Spot. The pepper is also subject to the attack 

 of an undetermined species of Phyllosticta, which causes 

 small circular greyish spots, with pycnidia in the 

 centre. 



BEAN 



Anthracnose. This disease (Figs. 80, 81) is due 

 to the fungus Colletotrichum lindemuthianum, Sacc. 

 & Magnus, and is widely distributed throughout the 

 bean-growing districts of the world. It attacks plants 

 of all ages and all parts above the ground, and is 

 carried in the seed. It can be detected on the young 

 plants, by the discoloured, sunken spots or cankers on 

 both stems and leaves. If the attack is severe, many 

 of the plants die. If the plant escapes death and 

 grows, the stems and leaves are more or less covered 

 with spots and cankers. Those on the leaves frequently 

 break into holes, giving an ugly, ragged appearance to 

 the plant. On the pods it causes canker-like spots, 

 which are usually circular or slightly irregular in 

 outline, and frequently have reddish margins. Within 

 these spots great numbers of spores are produced, and 

 are readily distributed by the rain and dew. 



Since the disease penetrates the pods and into the 

 seeds themselves, the planter should use care in the 

 selection of the seed. Diseased seedlings should be 



