Vegetable and Field Crops 



157 



Stem-rot, pod- 

 rot 1^' ''- 1^3 (Cortin 

 cium vagum). — 

 This disease is 

 manifest in three 

 forms: 



1. Damping-off 

 of seedHngs. See 

 damping-off. 



2. Dry-rot of the 

 stem. In this con- 

 dition the tissue is 

 dead, discolored, 

 and dry-rotted at 

 from 2-5 cm. above 

 the ground. The 

 rot extends to the 

 pith and usually 

 encircles the stem, 

 and thus so weak- 

 ens the plants that 

 they are often 

 broken by the wind. 

 In any event they 

 soon wilt and die. 



3. As brown 

 sunken areas upon 

 pods, penetrating to 

 and discoloring the seeds. 



Fig. 85. — Blight upon bean seeds. Alter Clinton. 



Fig. 84. — Blight of the bean. After Halsted. 



The germination of the seed is not 

 stopped by this 

 attack, and a 

 fruitful source 

 of dissemina- 

 tion is thus af- 

 forded. Such 

 seeds should be 

 avoided. 



