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DISEASES OF ECONOMIC PLANTS 



that the whole potato may give way in a few days after 

 infection. Other tubers, if they have broken surfaces or 

 wounds and He in contact with affected ones, will also be 

 infected. The rotten roots are therefore often found in 



Fig. 126. — Sweet potato soft rot. Original. 



groups through the pile. This rot is sometimes found in 

 the field, but is not usually destructive until after digging. 

 Normally it cannot enter a sound potato ; a wound must 

 furnish it a passageway. Therefore all wounded roots 

 should be laid aside for immediate consumption, and only 

 sound roots put in storage. 



