26 



THE CURLY-TOP OF BEETS. 



beets showing curly-top when harvested at the end of the preceding 

 season had again developed the symptoms. Of those showing no 

 symptoms when harvested, 83 per cent were affected on the same 

 date. Later in the season but 2 per cent of this latter batch was free 

 from visible symptoms of the disease, and even the 2 per cent was 



Fio. 7. — Mature healthy seed beet. (For comparison with seed beets affected with 



curly-top. ) 



checked in growth. Of the large number of beets siloed from the 

 major portion of the field, where practically no cases of the disease 

 had appeared during the preceding season and which were planted 

 out at the same time in the spring for seed production, about 10 per 

 cent had developed curly-top on May 24. It will be remembered that 

 no leafhoppers appeared until May 20, and then but few. 



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