26 



FARMERS BULLETIN 856. 



seed. In other cases the fungus penetrates the pods and enters the 

 seed, causing dark, sunken specks or spots. In these diseased seeds 

 as well as in the refuse from diseased plants the fungus is propa- 

 gated from season to season. 



^ Control. — It has been demonstrated conclusively 



y that anthracnose can be avoided by a careful system 



^ of seed selection. Save seed from perfectly healthy 



pods, selected with great care for entire absence of 

 spotting. Carefully keep them awa}^ from diseased 

 pods, shell by hand to avoid reinfection, and plant 

 on clean land. Pull and burn any plants showing 

 disease. 



In the absence of such disease-free seed (1) secure 

 for planting seed having the least possible amount 

 of disease, as shown by actual examination; (2) all 

 seed should be hand picked, and no seed showing the 

 slightest discoloration should be planted ; (3) practice 

 crop rotation, and 

 never plant beans 

 on land where there 

 is any refuse of last 

 year's crop; (4) do 

 not cultivate or 

 walk through the 

 bean field or pick 

 hile wet with dew or 

 rain. If the disease is present, it 

 is then easily spread from one part 

 of the field to another. 



BEAN BLIGHT. 



Bean blight differs from an- 

 thracnose in several ways. It is 

 caused by a bacterial organism. 

 On the leaves it produces irregu- 

 lar, diseased areas which at first 

 have a water-soaked appearance, 

 but later dry out and become brown and brittle, 

 pods the disease starts as slightly raised and watery pustules, which 

 later enlarge and become of irregular shape and amber in color. In- 

 fected seeds show yellow diseased blotches or are entirely yellowed 

 and shriveled. 



The bean blight is more difficult to control than anthracnose, but 

 the same methods will give the best results at present available. 



Fig. 23. — Boan an 

 thracnose. 



bear 



-Bean blight ou leaf and pod. 



(Fig. 24.) On the 



