INTRODUCTION 



Pome fruits — apple (Malus sylvestri Mill.), pear (Pyrus com- 

 munis L.), and quince (Cydonia oblong a Mill.) — must be handled 

 carefully and held under refrigeration until placed on the market 

 if quality is to be maintained and spoilage is to be held to a 

 minimum. According to Wiant and Bratley (136) 2 some spoilage 

 occurred in about four-fifths of the carlots of apples inspected 

 at New York City during 1935-42 and in about two-thirds of 

 those of pears. 



The word "disease" as used in this publication means any 

 departure from the normal or usual condition of fruits that 

 renders them inedible or otherwise undesirable for use by con- 

 sumers. Under such a definition, internal break-down of apples 

 is as truly a disease as is blue mold rot or scab. Internal break- 

 down, however, is a nonparasitic, or physiological, disease pro- 

 duced by environmental factors and the life processes of the fruit 

 itself, whereas scab and blue mold rot are produced by the action 

 of certain fungi that are referred to as the causes of the respective 

 diseases. 



Some of the more important facts concerning fungi (molds) 

 should be kept in mind in dealing with fungus diseases of fruits. 

 An important characteristic of most fungi is that they produce 

 minute bodies called spores, which are usually the most important 

 means by which fungi reproduce themselves and are distributed. 

 Being small and light, spores are easily carried by wind, rain, 

 insects, and other agents. Spores of several kinds of fungi that 

 attack fruits are quite common on the soil surface and on all 

 plant parts above ground. Spores on the surface of a fruit, under 

 favorable conditions, produce fine fungus threads that may enter 

 the fruit and cause disease. 



Fungus spores lie inert until temperature and moisture condi- 

 tions are favorable for their germination. The fungus threads 

 they produce may or may not enter the fruit through the unbroken 

 skin, but they are always more likely to enter if skin breaks are 

 present. Factors that favor the development of each disease in 

 storage, in transit, or on the market are discussed under appropri- 

 ate headings. 



Care During and After Harvest 

 pome fruits in general 



All fruits should be handled carefully through all stages of the 

 harvesting and packing processes. Unlike eggs, apples or pears 

 are not visibly ruined when they are dropped a foot or two. They 

 may sustain bruises or skin breaks, however, that during storage 

 or in transit may mean serious loss. In this connection, it should 

 be remembered that the susceptibility to fungus rots increases 

 as the fruits become more mature, and hence ripe fruits require 

 very careful handling at all stages of the marketing process if 

 excessive loss from rot is to be avoided. 



2 Italic numbers in parentheses refer to Literature Cited, p. 66. 



3 



