244 SCIENCE REMAKING THE WORLD 



rise to the condition known as "Black Heart." Dead 

 tissue of a vegetable or fruit will decompose and spoil 

 very quickly at ordinary temperature. 



One of the most important discoveries in connection 

 with respiration of potatoes is the fact that when they 

 have been stored for a period at low temperature and 

 then transferred to higher temperature their respiration 

 for a few days is very high but gradually falls to the 

 normal rate for the given temperature. This initial 

 period of abnormally high respiration may, under cer- 

 tain conditions, become an important factor in the keep- 

 ing qualities of cold-storage potatoes during their 

 transportation and marketing. These potatoes must be 

 supplied with very good ventilation, especially for the 

 first week or two after they are taken from cold storage. 

 For the same reason potatoes in late common storage 

 must be well ventilated. Experiments are now in prog- 

 ress to discover, if possible, storage conditions that are 

 generally satisfactory but that will not impose upon 

 the tubers the initial abnormal rate of respiration when 

 they are exposed to higher temperatures. 



Storage temperature is the most important factor in 

 controlling the growth of decay organisms as well as the 

 growth of sprouts in late storage. At temperatures 

 below 46 F. the damage due to rot organisms is very 

 slight. 



When all of the temperature effects are considered, 

 the selection o f the best storage temperature will be a 

 compromise and will probably vary somewhat with 

 the storage period. Temperatures ranging from 36 to 

 42 F. are now recommended for potatoes to be used 



