332 Diseases of Greenhouse Crops 



spots. The pycniospores are oblong, hyaline, and 

 one celled. 



Control, All dead and infected leaves should be 

 destroyed by fire, and the plants should be sprayed 

 with ammoniacal copper carbonate. 



ScHizANTHus {Schzzantkus pnnatus) 



Cultural Considerations. Schizanthus is forced 

 mostly as an early spring flower. It does not require 

 a very rich soil, and thrives best under night tem- 

 peratures of 45 to 50 degrees F. 



Diseases of Schizanthus. 



Schizanthi are very hardy plants. There is but 

 one disease recorded in the United States on the 

 greenhouse plants. 



Anthracnose 



Caused by Colletotrichum schizanthi Jen. and 

 Stewart. 



Symptoms. Anthracnose has been found by Jen- 

 sen and Stewart* to be a very destructive disease on 

 greenhouse Schizanthus. The younger parts of the 

 plant are usually more susceptible than the older 

 ones. On infected stems, branches, or petioles, the 

 disease causes watersoaked areas which extend in all 

 directions. The spots become depressed, and grow 



♦Jensen, C. N., and Stewart, V. B., Phytopath i: 120, 1911. 



