STUDIES OF DISEASE PRODUCING SPECIES OF FUSARIUM. 205 



were tested to determine the extent to which they would cause 

 decay of ripe apples. It was found that each of these caused 

 rot and at about the same rate as some of the well known apple 

 decay fungi which were 'being studied at the same time. Not 

 much work was done with these fungi ■ until the next summer 

 when green apples were inoculated and a decay was produced 

 in each case. The decay of the green fruit was regarded as 

 better proof that they are parasites than the rot of the ripe fruit 

 because a number of fungi are able to grow on ripe apples which 

 cannot attack green fruit. The organisms were re-isolated in 

 pure culture in a sufficient number of cases to make sure that 

 the decay was caused by the fungus with which the apple was 

 inoculated. These strains were designated Fusarium I and 

 Fusarium II from apple, or F I and F II. (See list on p. 222). 



In looking up the subject, no reference was found to any 

 report of a Fusarium decay of apples in America but it was 

 ' found that Osterwalder * had studied and described such a 

 decay in Europe. The fungus which causes the rot enters the 

 apples through the blossom end and grows down into the cavity 

 around the seeds spreading from here into the surrounding tis- 

 sues. The tissues become light browm in color and bitter to the 

 taste. 



Osterwalder studied the fungus not only as it occurs in nature 

 but in culture on a number of media and describes its charac- 

 teristics in some detail. He regarded it as a new species, F. 

 putrefaciens. Inoculations were made on both apples and pears 

 and it was found that when the fungus was placed in wounds it 

 caused decay, but attempts to produce infection through tiie 

 uninjured epidermis resulted in failure. Only one such apple 

 rotted and this rot was caused by another fungus, Cephalothe- 

 cium roseum Cda. 



The review of this article in Experiment Station Record, Vol. 

 XVII, p. 50, says : "The author claims that the fungus is iden- 

 tical with that reported by Eustace as Cephalothecimn roseum 

 which causes a rot of apples. He agrees with Eustace t and 



* Osterwalder, A. Ueber eine bisher unbekannte Art der Kernobstfaule 

 verursacht durch Fusarium putrefaciens Nov. spec. Centrabl. Bakt. 

 Zweite Abt. 13, 207-213; 330-338, 1904. 



t Eustace. H. J., N. Y., State Sta. Bnl. 227, 1902. 



