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Storage Rots. 



As every orchardist can testify, the loss from disease does 

 not end with the placing of fruit in storage. Most of the 

 diseases which occur on the fruit in the orchard may continue 

 to develop after harvest, and sometimes • the shrinkage of the 

 crop due to this is greater than on the tree. Scab, black-rot, 

 bitter-rot, brown-rot, spongy dry-rot, fruit-spot and bitter- 

 pit, all of which develop more or less on stored fruit, already 

 have been described. In addition, there are several rots 

 which occur only after the fruit has left the tree. 



Blue Mold. 



The rot caused by this fungus, Penicillium expatisum, is the 

 most common and destructive of all storage troubles. It is 

 frequently called soft-rot, and this name is descriptive of the 

 disease. The rotted tissue is light brown and watery and has 

 a musty odor and taste. On the surface of the rotted fruit 

 there develop white tufts of the mold, which soon turn blue- 

 green in color. From these tufts myriads of minute spores 

 are given off and each is capable of starting a new rotten 

 spot. (Fig. 20.) 



Apparently the fungus is unable to penetrate the sound 

 skin of the fruit. Bruises, wormholes, scab or other disease 

 spots, stem punctures or any other wounds offer easy access, 

 and once the fungus gets into the flesh it causes rapid decay 

 of the fruit. The disease spreads from one fruit to another, 

 either through contact or by scattering of the spores. Soft- 

 rot is primarily a disease of overripe or injured fruit. 



Cold retards development of the fungus, but apples which 

 have become overheated may continue to rot when affected 

 by it, even after being cooled to cold-storage temperatures. 

 Fruit that is carefully picked, sorted and packed and placed 

 in storage at 32 degrees F. within forty-eight hours after 

 picking will escape much of the trouble from this source. 

 Wrapping with paper to prevent contact will do much to 

 reduce the amount of soft rot. 



