Dracenas Diseases 251 



Leaf Spot and Tip Blight 



Caused by FJiysalospora dracena Sheld. 



The conidial stage as first mentioned by Halsted 

 is a species of Gloeosporium. However, the ascus 

 stage was found by Sheldon,* who named it Physa- 

 lospora dracentz. The disease is generally confined 

 to the tip of the foliage (fig. 53, a.). The affected 

 tissue becomes straw colored and shrunken. The 

 disease may be controlled by spraying with a stand- 

 ard fungicide. 



Phyllosticta Leaf Spot 



Caused by Phyllosticta macuUcola Hals. 



Dracenffi, particularly the beautiful species 

 Cordyline terminales, are often subject to a leaf 

 spot which renders them worthless. The disease 

 attacks plants of all ages and sizes. 



Symptoms. The trouble is characterized by small, 

 brown, somewhat angular spots on the leaves (fig. 

 53, b.). The tissue adjoining the spots becomes 

 yellowish in color. Within these spots may be 

 found minute black bodies (pycnidia) from which 

 the spores, when ripe, ooze out as long colorless 

 tendrils. Little is known of the organism. The 

 disease may be controlled by spraying. 



'Sheldon, J. L., Jour. Myc. 13: i38-i4(^ 1907. 



