MARKET DISEASES OF APPLES, PEAES, QUINCES 3 



or two. They may sustain bruises or skin breaks, however, that 

 under favorable conditions in storage or in transit mean just as 

 nearly total loss as if the fruits had been mashed or broken in pieces 

 while being harvested or packed. In this connection it should be 

 remembered that the susceptibility to fungous rots increases as the 

 fruits become more mature, and hence ripe fruits require especially 

 careful handling at all stages of the marketing process if excessive 

 loss from rot is to be avoided. 



It is highly important, also, that packing houses, packing-house 

 machinery, and the immediate surroundings of packing houses should 

 be kept free of all cut, mashed, or decaying fruits and all fruits 

 culled out of the pack for any reason. A few apples or pears af- 

 fected with blue-mold rot or gray-mold rot, if run through grading 

 machines or left lying on the floor in out-of-the-way places, can 

 produce enough spores to make them a serious source of danger to 

 all the fruit that passes through the house. Stacks of field boxes 

 filled with rotting culls give up spores to every wind that blows over 

 them. If they stand inside the packing house, or near doorways, 

 even though outside, they mean trouble. The safest procedure is to 

 get them away from the house as soon as possible and to clean up 

 the grading machinery and bins and the packing-house floor at least 

 once every day. It is desirable to have the floor of the house tight, 

 to keep mashed and decaying fruit from dropping through to the 

 ground below and there becoming a source of fungus infection. 



At various places in the pages that follow, descriptions are given 

 of injuries that may result from the washing of apples or pears to 

 remove spray residue. It cannot be too often emphasized, however, 

 that if the washing is done with proper equipment and care and 

 under desirable sanitary conditions, neither the market value nor 

 the keeping quality of the fruit will be impaired ; on the contrary, 

 both are generally enhanced {68^ 69).^ 



The common names of diseases used in this publication are for the 

 most part those that have become well established in the literature of 

 plant diseases and are in general use among persons concerned with 

 the growing and marketing of apples, pears, and quinces. A few, 

 such as Jonathan spot and York spot, indicate the name of the 

 variety on which they were first described or on which they are most 

 common. Some of the names, such as bullseye rot, flyspeck, and 

 scald, are briefly descriptive of the diseases to which they are applied. 

 Still others contain the name of the causal or inducing agent; 

 among these are Alternaria rot, drought spot, and freezing injury. 



A few of the names imply a quality of the affected tissues which 

 is not really characteristic or typical, but they are so well established 

 by usage that it has seemed best to retain them. The diseased flesh 

 of apples affected by bitter rot and bitter pit is not often bitter; 

 " black rot " lesions are usually only dark brown, whereas " brown 

 rot " lesions eventually become black. 



Most of the insect injuries are named for the insect that causes 

 them. 



^Italic numbers in parentheses refer to Literatm-e Cited, p. 59. 



