244 



VEGETABLE GARDENING 



he of the best quality because this will vaporize without 

 any residue. The vapor of this substance is very in- 

 flammable and the work should, therefore, be done at a 

 distance from other buildings and no light of any kind 

 1)6 Ijrought near." 



317. Anthracnose (CoUctotyichuiii lagciiariiiin) is the 

 most common and the most destructive of the bean dis- 

 eases. It is a fungous disease, which attacks all parts 

 of the plant except the roots. Diseased seed is often 

 the source of the malad}^. The young 

 tender stems ma}^ become affected and 

 the plants killed when conditions are 

 favorable for the parasite ; or it some- 

 times appears later on the pods, as well 

 as on other parts of the plant. The 

 disease is very noticeable on the yellow 

 pods of wax varieties, which are reduced 

 in value or rendered unfit for market 

 purposes. Figure 62 illustrates the dis- 

 eased pods. The Cornell Station (Cor- 

 nell Station Bulletin 255, p. 436) makes 

 the following statement in regard to 

 this disease : "The spots or cankers are 

 black with reddish or yellowish mar- 

 gins. IMost growers are also familiar 

 with the disease on the seed itself, espe- 

 ciallv on the white beans, where it makes rusty, red spots 

 of various sizes, sometimes involving nearly the entire seed, 

 though ordinarily onl}' producing a slight discoloration 

 on one side. The disease enters the seed by way of the 

 pod, the fungus penetrating from the outside into the 

 young and tender seed. . . . When the diseased 

 seeds are planted in the soil, and first come through the 

 ground, the_v are sure to show the small black cankers 

 on the cotyledons or seed leaves and a little later on the 

 stems." 



FIG. 62. BEAN 

 ANTHRACNOSE 



