370 Journal of Agricultural Research voi. xxii. no. 7 



SUMMARY 



Plum blotch, a hitherto unknown disease of the Japanese plum {Prunus 

 iriflora), has been found in Georgia. In addition to the fruit, the leaves 

 and possibly the twigs are affected. The lesions on fruit and leaves 

 greatly resemble those of the apple caused by Phyllosiicta soliiaria 

 E. and E. 



Varieties Abundance and Burbank were found to be susceptible. An 

 unnamed seedling, probably also belonging to Prunus iriflora was found 

 to be severely infected. 



From diseased fruits and leaves the fungus, Phyllosiicta congesta Heald 

 and Wolf, was isolated and grown in pure culture. Spores obtained from 

 cultures on sterile apple twigs when suspended in distilled water and 

 sprayed on healthy fruits and leaves produced characteristic lesions of 

 the disease. 



Phyllosiicta congesta Heald and Wolf is to be considered for the present 

 as different from P. soliiaria E. and E-, though greatly resembling it. 

 Inoculation experiments on plums using spores from pure cultures of P. 

 soliiaria were negative. 



No attempts have been made to control plum blotch, but the possibili- 

 ties of control are discussed. 



