282 PLANT DISEASES 



packed conidiophores, each bearing a single conidium at 

 its tip. Eventually the epidermis of the apple is split at 

 the apex of each pustule, and the spores escape in the 

 form of a slender tendril, held together by mucus. In the 

 case of stored fruit, if these spores come in contact with 





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Fig. 75. — Gloeosporium fruciigenum. i, appearance 

 of the disease on an apple; 2, showing the apex of one 

 of the black pustules or fruit of the fungus ; the spores 

 are escaping stuck together into a thread or tendril, 

 through a rupture in the epidermis of the apple, x 50 ; 

 3, section through one of the pustules showing the 

 conidiophores bearing conidia at their tip, x 50 ; 4, three 

 conidiophores, each bearing a conidium at its tip, x 300. 



healthy apples, the disease is communicated, and in a very 

 short time the disease spreads through the entire stock. 

 A second and higher form of fruit is suspected, but the 

 genetic connection is not yet proved. 



It has been proved in the United States that this fungus 

 also attacks grapes, pears, peaches, etc. 



