Notes on some Sugar-Cane Matters. 



123 



Leaf Diseases. 



Leaves of tlie sugar-cane are subject to a luunber of leaf spot 



diseases caused by fungi. The two most commonly niet with here 



are the "ring-spot" (Fig. 2), caused by the fungus Leptosphaeria 



sacchari, and the " eye-spot " caused by the fungus Hclminthosponum 



sacchari. . • , i i 



These diseases are especially bad during moist, cool seasons and 



Fig. 1. — Root disease of cane. Tbe fungus is evident on the 

 cutting and on the basal leaves of the young shoots. 



in noist, cool localities. A Phoma fungus is usually associated with 

 the Leptosphaeria, and is only a stage in the life-cycle of the \attei\ 



Killing areas of the leaf tissues, these fungi interfere with the 

 normal function of leaves as builders up of starch and of sugar trom 

 the carbonic acid gas of the atmosphere. 



