and St. Kitts. They concluded that the fungus is merely a facul- 

 tative wound parasite, gaining entrance largely through borer holes, 

 and that the disease was not communicated by infected cuttings. 



In addition to the above there are reports of occurrence by South 

 (70, 71), Ballon (4), No well (64, 65), and Dash (18), in Barbados, 

 Antigua, St. Kitts, and St. Lucia. The senior author reported (49) 

 it from Santo Domingo. It is mentioned by Averna Sacca (100) 

 as one of the cane diseases of Brazil. 



Tryon (87) mentions red rot as one of the cane diseases of Queens- 

 land and Stockdale (78) in reports of the agricultural department 

 of Mauritius gives an account of its occurrence on that Island. 



Bed Rot in Porto Rico. — The losses due to this fungus in Porto 

 Eieo in no way compared with those reported from other countries. 

 It is of interest to note that this fungus, which occurs in most cane 

 countries, varies greatly in its virulence as indicated in the discus- 

 sion above, Porto Rico being one of the regions in which it is for 

 the most part a wound parasite only. In a very few instances it 

 has, in connection with a lack of water, destroyed cane over small 

 areas, one field of less than one hundred acres being the only serious 

 case observed. There are indirect losses through a decrease in effec- 

 tive leaf surface, and through its growth in connection with borer 

 injury, or Melanconium and other fungi, l)ut these are of sucli a 

 nature that it is impossible to give any estimates. 



The fungus very commonlj^ occurs in stalks injured by the moth 

 stalk-borer {Diatraea saccharalis) or other causes, producing a red 

 discoloration internally, but no external sjrtntoms, at least as long 

 as the cane remains green. Development of the fungus may be fast 

 or slow according to the variety and the vigor of the cane. The 

 damage caused is, however, more than is apparent since the fungus 

 very quickly inverts the sucrose to a considerable extent, raising 

 the glucose ratio. The relation of Colletotrichum to the inversion 

 of sucrose has l)een considered by all of the various workers who 

 have investigated the matter to any extent, and all have agreed tliat 

 this represents the serious phase of the disease. 



To a more limited extent, the fungus occurs independent of borer 

 holes but it is generally possible in such instances to find some other 

 weakening influence, drought, root disease, or other fungi. It fre- 

 quently happens that young shoots are crowded out hy more vigorous 

 ones in a stool and wither away, and in such cases this fungus may 

 commonly be found, although, even then, the moth-borer, or otlier 

 insect or root disease may be the initial cause. Where large areas 

 of cane are attacked it has generally been found that there have 



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