174 



DISEASES OF CULTIVATED PLANTS 



BOTRYOSPHAERIA (Ces. and De Not.) 



Stroma innate, subrotund, brownish ; asci clavate, 

 8-spored ; paraphyses present ; spores elongated, hyaline, 



continuous. 



Briar scab. This disease, caused by Botryosphaeria 

 dothidea (Ces. and De Not.), now and again appears as an 

 epidemic in a garden, and amongst cultivated roses, it 



44. Botryosphaeria diplodia. 



1. fungus 011 portion of stem of a wild 

 rose, reduced ; 2, ascus containing 

 8 s|K>res, highly mag. 



appears to exercise mu< h discrimination in the choice of a 

 host. In one garden a bed of ' Solcil D'Or,' and another 

 bed of 'Caroline Testout,' about thirty yards apart, had every 

 plant in each bed badly infected, whereas intervening beds 

 of roses showed no sign of disease. Wild roses throughout 

 the country are frequently met with in a diseased condition. 

 The fungus forms large, slightly raised, black scabs, cracked 

 more or less concentrically, on the bark. 



