Antirrhinum Diseases 203 



The Organism. The stroma is well developed; 

 the conidia are straight to curved, with both ends 

 rounded. The conidiophores are short, the setae 

 abundant, dark brown, simple, and mostly straight 

 (fig. 40, e and f). 



Control. The disease is often introduced in the 

 greenhouse with infected cuttings. Cuttings should 

 therefore be secured from healthy plants. This 

 disease attacks only the snapdragon. It should 

 therefore be an easy matter to prevent its introduc- 

 tion indoors. If the disease makes its appearance, 

 spraying with Bordeaux mixture should be resorted 

 to. All diseased material should be destroyed by 

 fire. 



Branch Blight 



Caused by Phoma poolensis Taub. 



Symptoms. The disease seems to be confined to 

 the tender and growing shoots. It seldom affects 

 the older and more woody stems. Affected parts 

 wilt, and become discolored without showing any 

 definite spotting. Later, however, numerous pycni- 

 dia appear on the dead parts. 



The Organism. — Stewart* has proved by artificial 

 inoculation that the causal organism is a parasite. 

 The writer's investigation of this organism has con- 

 firmed the work of Stewart. In 1916 and 1917, a 

 careful study of this disease was made, as it occurred 

 in several greenhouse establishments in San Antonio, 



•Stewart, F. C, New York (Geneva) Agr. Expt Sta. Bui. 

 179: 109-110, 1900. 



