REPORT OF CRANBERRY SUBSTATION FOR 1916. 239 



From a sample of cranberries of the cherry variety taken July 2, 1917, 

 at Madrid, Me., which had been kept in the cellar of a house all winter, 

 50 softened berries were chosen at random and cultures were made from 

 their pulp, as described above. Twenty of these berries, or 40 per cent., 

 jielded the end-rot fungus, while 22 berries, or 44 per cent., showed no 

 fungi, and were presumably destroyed by the other causes discussed in 

 this paper. 



Effect of Carbon Dioxide on Fungi in the Berries. 



That carbon dioxide in high concentrations injures fungi in the cran- 

 berries as well as the berries themselves is indicated by a test in which equal 

 numbers of rotten cranberries from a single lot were placed in similar ves- 

 sels, one of which was filled with carbon dioxide and the other left open. 

 At the end of one week transfers of tissue were made from each berry. Of 

 the berries which had been kept in an atmosphere of carbon dioxide 70 

 per cent, contained no viable fungi and the others yielded Penicillium, or 

 the end-rot fungus. Of the berries kept in the open vessel only 15 per 

 cent, contained no living fungi, and the others yielded fungi of six different 

 species. 



The rate at which carbon dioxide is given off by cranberries in storage 

 and the variation of this rate with temperature, the concentration of the 

 gas necessary to cause injury, and the concentration which occurs under 

 storage conditions, have not been determined, and further investigations 

 on this line are planned. It seems very probable from the facts now in 

 hand, however, that this spoilage is a considerable factor in the loss during 

 storage, and throws new light on the results of Dr. Franklin, ^ which indi- 

 cate the importance of ventilation, as well as on this year's results in 

 shipping cranberries in tight as compared with ventilated packages. 



1 Franklin, H. J.: Report of Cranberry Substation for 1915, Mass. Agr. Expt. Sta., Bui. No. 

 168, 1916. 



