STUDIES OF DISEASE PRODUCING SPECIES OF FUSARIUM. 24I 



that the Fusarium isolated from wheat, F VIII, and which 

 agreed closely with F I from apples caused a distinct decay of 

 these apples. A Fusarium isolated from cucumber, F VII, and 

 which agrees closely with the strains carried as F. oxysporum 

 from potato caused as much decay of apples as any fungus 

 which was used in this set of inoculations. 



Green Mcintosh apples were inoculated August lo, 1911, 

 with strains of Fusarium, F I to F XXVI. The fungi made 

 some growth of mycelium at the points of inoculation but did 

 not spread into the green fruit to cause much decay. 



September i, 1912, Duchess apples were inoculated with 

 strains of Fusarium from 34 sources. Observations from time 

 to tim.e for one month showed that all of these fungi made a 

 little growth but that none of them caused much rot. 



January 9, 1913,- one ]\Iann apple and 2 Baldwins were inocu- 

 lated with material of each of 7 strains of a fungus, F XLVII, 

 of the type of F I from apple. Each strain was isolated from a 

 different decaying Milden apple. 



One week after inoculation there was a decayed region about 

 1.5 cm. in diameter at each of the two points of inoculation on 

 each Alann apple. Little difference could be noted in the decay 

 caused by the different strains. The decay spread more slowly 

 in the Baldwin than in the Mann apples. One month after inoc- 

 ulation the Mann apples were almost entirely rotted while the 

 Baldwins showed decayed areas 2 to 3 cm. in diameter. 



January 17, 1913, Bellflower apples were inoculated with 40 

 strains of Fusarium isolated from different sources. One week 

 later all of the fungi showed some growth at the points of inocu- 

 lation. The strains of F XLVII from Milden apples caused 

 decay more rapidly than any of the others. Later observations 

 showed that strains of this fungus whether isolated from apples, 

 wheat, or potato caused more decay of apples than any other 

 forms used. The forms with obovate spores from various 

 sources did not cause nearly so much decay in this set of inocu- 

 lations as the fungi of the type of F I from apple. There was 

 in some cases considerable difference in the amount of decay 

 in different apples inoculated with material from the same cul- 

 ture. The results of the inoculation work would seem to justify 

 the conclusion that a number of species of Fusarium may cause 



