76 HISTORY OF PHYTOPATHOLOGY 



tural College in Berlin in 1881, he remained there for 

 eighteen years until his death, September 27, 1900. Born 

 the same year as Hartig, he lived but one year less. Both 

 were outstanding German pathogenetists of their time. 



Frank's chief contributions to phytopathologic research 

 were: (1) his discovery of the true cause of the leaf 

 scorch of cherries, 1 a disease which became epiphytotic in 

 Germany about 1880 and threatened the destruction of 

 all sweet cherry trees. He showed this to be due to the 

 ascomycete Gnomonia erythrostoma which winters over 

 on the leaves hanging to the tree. With German 

 soldiers placed at his disposal he picked all these leaves 

 for two seasons, claiming to have thereby effected the 

 control of the disease; (2) his discovery of the cause of the 

 heart and dry rot of sugar beets. 2 This disease so threat- 

 ening to the sugar-beet industry he showed to be due to 

 the fungus Phoma beta. 



Frank's career as a plant pathologist really began with 

 his call to the chair of plant physiology in the Koniglichen 

 Landwirtschaftlichen Hochschule in Berlin in 1881, al- 

 though the first edition of his text-book on plant diseases 

 had appeared the year previous. The second edition of 

 this text-book appeared in three volumes in 1 895-96. a 



'Frank, A. B.: tiber Gnomonia erythrostoma, die Ursache einer 

 jetzt herrschenden Blattkrankheit der Siisskirschen im Altenlande, 

 nebst Bemerkungen iiber Infection bei blattwohnenden Ascomyceten 

 der Baume iiberhaupt, Ber. Deut. Bot. Ges., 4 : 200-205, 1886; also, 

 Uber die Bekampfung der durch Gnomonia erythrostoma verursachten 

 Kirchbaumkrankheit im Altenlande, Ber. Deut. Bot. Ges., 5 : 281-286, 

 1887. 



2 Frank, A. B.: Phoma Betae, ein neuer Riibenpilz, Zeitschr. Pflanz- 

 enkr., 3 : 90-92, 1893. 



3 Frank, A B.: Die Krankheiten der Pflanzen, 1 : 1-XII + 1-344, 

 1895; 2 : 1-XI + 1-574, 1896; 3 : 1-IX + 1-363, 1896. 



