214 



Journal of Agricultural Research voi. xviii, no. 4 



have shown no sign of injury and have developed less scald than similar 

 apples held in air that was free from carbon dioxid. It was also found 

 that apples could be made less susceptible to scald by storing them for 

 a few days in an atmosphere composed entirely of carbon dioxid but 

 that this treatment sometimes gave the apples a disagreeable alcoholic 

 taste. In order to get further data as to the carbon-dioxid endurance 

 of the apple, these latter experiments were repeated in the fall of 191 8 

 with the period of storage in carbon dioxid shortened. The results are 

 given in Table I. lyOts A, B, and C were Grimes from Vienna, Va. 

 They were picked August 20 and the experiment started the following 

 day. The apples in lot D were Grimes from Wenatchee, Wash. They 

 were shipped to Washington, D. C, in a pony refrigerator and the experi- 

 ment started September 20. Lot E was Yellow Newtown apples from 

 Winchester, Va. They were in cold storage until December 19, the 

 date of starting the experiment. In all the tests the apples receiving 

 prestorage treatment with carbon dioxid were removed from this gas 

 at the end of the given number of days and stored in moist chambers 

 in normal air. Thereafter they had the same air and moisture condi- 

 tions as the controls had from the beginning of the experiment. 



Table I. — Effect of prestorage treatment with carbon dioxid upon the development of 



apple-scald 



At the end of the various experiments the apples that had been 

 treated with carbon dioxid were slightly greener than the untreated 

 fruit but were apparently normal in taste and general appearance. A 

 study of the last two columns of the table will show that the apples 

 exposed to carbon dioxid developed much less scald than those that 

 were not, giving further evidence that carbon dioxid has no tendency 

 to produce the disease. The writers are of the opinion that the appar- 

 ently beneficial effects of the carbon dioxid treatment are due to a general 

 checking of the skin activities of the apple rather than to any specific 



