THE PESTS AND DISEASES OF THE CANE. 



A disease similarly characterized was described in 1849 by Bojer 27 in 

 Mauritius, who attributed it to electrical influences in the atmosphere. 



10. Yellow Stripe Disease. (Gele Strepen Ziekte.) This is a leaf disease 

 often referred to in the Java literature, and as yet imperfectly diagnosed. Some 

 references show points of similarity with the ' leaf splitting' disease of Hawaii. 



11. Broivn Leaf Spot. Cercospora longipes. The disease due to this 

 organism is described by Butler as prevalent in North and South Behar; 

 narrow oval spots about inch long and of a reddish colour are the first signs of 

 the disease ; as the spots increase in size a brown centre becomes evident, and 

 at one stage of the disease three concentric rings, brown, red and yellow, are 

 seen ; eventually the spot become a broad oval deep brown ring, with a straw 

 coloured centre. The rings are usually from a quarter to a third of an inch 

 long by an eighth of an inch or more in breadth. The technical description of 

 this fungus is: Cercospora longipes. Maculis elongatis, amphygenis, saepe con- 

 fluentilus, primo sangwneis, orescendo stramineis, Irunneo-cinctis ; hyphis in 

 caespitulos gregarios collectis, plerumque hypophyllis flexuosis, Irunneis, sursum 

 geniculatis vel denticulatis, 100200 X 4 conidiis obclavatis sursum attenuatis, 

 rectis vel curvatis, ! 6 septatis, 1^080x5 hyalinis. In Fig. 65 are shown 

 (after Butler) spores of this fungus. 



x 130 



FIG. 65. FIG. 66. 



Diseases of the Leaf Sheath. 



1. Eye Spot of the Leaf Sheath. Cercospora vagina. Kriiger. This 

 disease is characterized by a brick red spot appearing on the leaf sheath; 

 this red colouration does not spread over the leaf sheath ; the centre of this 

 spot becomes eventually black. The disease is due to the organism Cercospora 

 vagina ; Kriiger gives the length of the spores as from 19-640 microns, 

 with an average length of 25*2 microns, and the breadth as seven microns. 

 In Fig. 66 are shown (after Kriiger) spores of this fungus. 



2. Ited Rot of the Leaf Sheath. 31 The organism causing this disease 

 is imperfectly known ; the disease is characterized by the leaf sheath becoming 

 red, the red colouration spreading all over the sheath, and shading off into 

 an orange colouration. The disease passes from the leaf sheath to the stem, 

 attacking the soft parts near the nodes ; at a late period of development the 



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