614 The Philippine Journal of Science 



SUMMARY 



1. A disease exists in Japan upon the Wase Unshiu orange 

 variety, which has been observed to cause a loss of 20 per cent 

 of the crop and is capable of causing even greater losses. Al- 

 though the disease is confined to this one variety in nature in 

 Japan, inoculation experiments have shown that at higher tem- 

 peratures the disease will affect other varieties of the Unshiu 

 oranges and also mandarin oranges. 



2. The disease is described and isolation and inoculation exper- 

 iments are reviewed showing the disease to be caused by a 

 fungus identical with Gloeosporium foliicolum Nishida. 



3. Inoculation experiments with this fungus on different Citrus 

 species are also reviewed, indicating in a preliminary way that 

 Gloeosporium foliicolum is a valid species and distinct physio- 

 logically from Gloeosporium limetticolum and Collet otrichum 

 gloeosporioides. It is pointed out that, in the light of inocula- 

 tion experiments, countries where this disease is not yet reported 

 are justified in preventing the introduction of this fungus. 



LITERATURE CITED 

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