tions. The two fimgi obtained remained true to type in cultures. 

 October 22 a second series was commenced from which Colletotrichum 

 C was obtained from ten tubes, Colletotrichum B from two, and Melan- 

 Gonium saccharinum from one. Further cultures were made in De- 

 cember, from which form C only was obtained. No inoculation tests 

 were made at this time. 



In 1916-17 further tests were made of the red-stripe disease. 

 In the first series of inoculations ^ using a culture of Colletotrichum 

 falcatum isolated from a diseased stalk, typical striping resulted in 

 all cases (ten) and but one of ten checks showed any signs of infec- 

 tion. A second series of twenty-nine inoculations gave the same 

 result, two out of nine checks also showing striping. All inoculations 

 were made with a hypodermic needle. The cane showed some red 

 striping other than the inoculations, explaining the two checks 

 diseased. 



A third series of puncture inoculations of the midrib was made 

 using pure cultures of Melanconium sacchari, Thielaviopsis paradoxa, 

 Cytospora sacchari, Sclerotium Bolfsii, and Trichoderma lignorum. 

 With the exception of the latter all produced red striping, varying 

 somewhat in tlie shade of red, but otherwise characteristic of the 

 disease. Sclerorotiuni stripes were of a decided orange-red color. 



A similar series, using Melanconium, Colletotrichum C, Colletotri- 

 chimi falcatum, Cercospora vaginae, Cytospora, Thielaviopsis, and 

 Sclerotium, gave .similar results. There was considerable variation 

 in color, the two Colletotrichum s giving the typical color. Melan- 

 conium, [indThielaviopsis gave doubtful results. It was possible to 

 reisolate a majority of the fungi used. 



A further series of laboratory dam])-cliamber tests, short externally 

 sterilized sections of reddened mid-ribs being used, gave C. falcatum 

 four times, Colletotrichum C. once, and an ascomycete (undet.) once. 



It is apparent from these studies that more than one form is con- 

 cerned in the red stripe disease, although Colletotrichum falcatum 

 and related forms are most abundant. A wide range of fungi when 

 introduced into a wound are capable of producing red stripes. Red 

 striping is common where a leaf has been injured, but is also equally 

 common where there are no signs of injury. Certain forms commonly 

 found in this connection are here tentatively described. 



CoLLETOTRICHUiM .\. 



Typically small hyaline, slightly falcate spores, forming a cottony 

 white growth on potato cylinders, which become somewhat bluish in 



1 Inoculations made by K. C. Rose, assistant pathologist. 



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