Lee: A Disease of Orange Fruits 



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rotting of the fallen fruits proceeds more rapidly. As a gen- 

 eral thing fruits affected with this disease are a total loss to 

 the grower. The colored photograph, Plate 1, probably gives a 

 better idea of the disease than does the written description. 

 This disease has been called in the field Wase Unshiu rot, be- 

 cause the disease in nature has been confined to the Wase Unshiu 

 variety and the word rot is fairly descriptive of the trouble. 

 Probably, for the use of pathologists, the term anthracnose of 

 Unshiu oranges would be more descriptive. 



THE CAUSE OF THE DISEASE 



Attempts at isolation of a causal fungus were first made with 

 fruits obtained at Saigo. The isolation attempts resulted 

 uniformly, a fungus of the genus Gloeosporium being obtained 

 in every planting in each plate. This fungus was maintained 

 in pure culture and inoculated into perfectly healthy fruits of 

 the Wase Unshiu orange. The inoculation data and results are 

 given in Table 1. 



TABLE l.Showing results of inoculation experiments to reproduce Wase 

 rot on ripe Wase Unshiu orange fruits. Inoculations made with 

 needle punctures in fruits in moist chambers at laboratory temper- 

 aturr* °6 to 30° C, on October 2, 1919; results observed October 



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