24 BULLETIN 601, U. S. DEPARTMENT OF AGRICULTURE. 



lettuce drop and is said to be due to the same organism. Signs of 

 it in storage are often first found on the leaves. It causes a soft, 

 slimy decay that may consume the leaves entirely before seriously 

 injuring the celery stalks. The disease causes the stalks to become 

 discolored and watery and renders them unfit for consumption. 

 Forms of this disease are encountered frequently in the field. The 

 common foot-rot is said to be due to the same or a closely related 

 organism. 



Heart-rot is a term used to describe the darkening of the leaves 

 and stalks forming the central bud or heart of the plant. This 

 part first turns brown and later black, as the trouble develops. 

 Heart-rot is found very often in the celery fields, especially late in 

 the season. It appears to originate in the field, although some 

 plants may have merely a predisposition to the disease at the time 



PREC00LED 



PER CENT DECAY 

 S 20 15 10 6 



SO FT- ROT 



STORED TWO WEEKS 

 STORED FOUR WEEKS 



HEART-ROT 



STORED TWO WEEKS 

 STORED FOUR WEEKS 



TOTAL DECAY 



STORED TWO WEEKS 

 STORED FOUR WEEKS 



NON PREC00LED 



PER CENT DECAY 

 S 10 1$ 10 2S 30 35 40 4 











■■47 



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Fig. 17. — Diagram illustrating the percentages of soft-rot, heart-rot, and total decay at the end of two 

 weeks and at the end of four weeks in storage at 32° F. in both precooled and nonprecooled celery 

 shipped from Manatee, Fla., to New York, season of 1915. 



they are cut and show no signs of it. It does not appear to spread to 

 adjoining bunches in storage, but its development seems to bear some 

 relation to the temperature to which it is exposed. 



Leaf-spot also is a serious trouble, -especially if celery is affected 

 before being harvested. It frequently develops to an injurious ex- 

 tent in storage and is sometimes the cause of serious losses. Every 

 effort should be made to control the leaf-spot and other diseases 

 in the field through proper spraying and cultural practices. Celery 

 entering storage in a diseased condition can not be held satisfactorily, 

 even under the most favorable temperature and storage conditions. 



RESULTS OF STORAGE EXPERIMENTS. 



Summaries of the average results of the inspection of all the experi- 

 mental lots of celery are given in the following tables and diagrams. 



Table X and figure 17 show a comparison of the decay in the pre- 

 cooled and nonprecooled celery. The principal point brought out 



