MARKET DISEASES OF VEGETABLES. 27 



BEAN: WATERY SOFT ROT; SCLEROTINIA ROT. 



(See Watery Soft Rot) . 



BEET: BLACK ROT. 



Cause: A fungus (Phoma betae). 



In this rot, the affected tissue is coal black, rather firm 

 and extends deeply into the root. There is no bad odor. 

 The surface becomes somewhat shrunken, and often bears 

 the black pycnidia of the causal fungus. 



This disease causes a leaf spot and a blight of the plants 

 in the field. The fungus is carried with the seed. 



Control consists of seed and seed-bed sanitation and re- 

 moval of diseased leaves from roots previous to storage. 



Ref. (17). 



BEET: LEAF SPOT. 



Cause: A fungus (Cercospora beticola). 



This disease occurs only on the leaves where its lesions 

 appear as distinctly circular spots with purple borders and 

 tan to ashen gray centers. Leaves may be killed by the 

 coalescence of numerous lesions. The death of the older 

 leaves may cause the crown to elongate, thus affecting the 

 shape of the root. 



Beet leaf spot is widespread in its occurrence and is of 

 considerable economic importance in the field. In the sugar 

 beet crop, it lowers the efficiency of the leaves as sugar pro- 

 ducers. In the market, leaf spot predisposes the leaves to 

 the attack of slimy soft rot. 



Spraying with Bordeaux mixture will control the disease. 



Ref. (40). 



BEET: SLIMY SOFT ROT; BACTERIAL ROT. 



(See Slimy Soft Rot). 



BEET: GRAY MOLD ROT; BOTRYTIS ROT. 



(Se&Gray Mold Rot). 



BEET: WATERY SOFT ROT; SCLEROTINIA ROT. 



(See Watery Soft Rot). 



BEET: NEMATODE DISEASE. 



(See Nematode Disease). 



BEET: MISCELLANEOUS DISEASES. 

 ROOT ROT. 



Cause: A fungus (Rhizoctonia). 



This rot starts typically from the crown, and progresses 

 downward from the leaf bases. 

 Ref. 417). 



SCAB. 



Cause: A fungus (Actinomyces scabies). 



