82 PARASITES BELONGING TO THE GENUS GLOMERELLA. 



DEWBERRY TO APPLE. 



On October 2 three apples were inoculated by puncture with conidia 

 from a culture from dewberry. At the end of a month only one apple 

 showed a decayed spot, 1.75 inches in diameter. Small decayed spots 

 occurred on the other two apples at points of inoculation 26 days 

 later. 



On October 12 four Willow Twig apples were inoculated by punc- 

 ture with conidia from a culture. At the end of three weeks only 

 one fruit showed development of rot, about 1.75 inches in diameter. 



On October 26 three apples were inoculated by puncture with 

 conidia from culture from the apple previously inoculated from dew- 

 berry. Only a slight decay occurred about the point of inoculation 

 after several weeks and no acervuli formed. Cultures made from 

 these decayed spots produced acervuli. 



DEWBERRY TO APPLE TO AGAR TO APPLE. 



On December 7 three apples were inoculated by puncture with 

 conidia from an agar culture made from the fiist apples inoculated 

 from the dewberry. Infection followed in all cases. Decayed 

 spots 0.5 to 0.75 inch in diameter developed in six days, but no 

 acervuli were produced. 



DEWBERRY TO APPLE TO APPLE TO AGAR TO APPLE. 



On January 3 three apples were inoculated by puncture with conidia 

 from a pure culture made from the second generation of the dewberry 

 fungus on apples. Infection followed in all cases. The decayed spots 

 developed more rapidly than in the previous generation and abundant 

 acervuli were formed. 



On January 10 three apples were inoculated by puncture with 

 conidia from a culture from the second generation grown on apple. 

 Infection followed in all cases. Decayed spots an inch in diameter 

 developed in 10 days and numerous acervuli appeared. These experi- 

 ments seem to indicate that the dewberry form of Glomerella becomes 

 quickly adapted to growth on apples, developing in the third genera- 

 tion about as rapidly as the fungus taken directly from apples and 

 producing typical rot and acervuli. 



DEWBERRY TO GRAPE. 



On October 16 eight berries were inoculated by puncture with 

 conidia from a culture from the same strain of the dewberry Gloeo- 

 sporium used in the inoculations with apples. At the end of two weeks 

 some rot was found, but no acervuli were ever produced. 



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