4l6 First European Journey 



some evidence of progress."^ The etiology of several diseases of 

 plants, now known to be of virus origin, was being studied. But 

 many of the problems were not understood. Curly top has been 

 shown to be a disease caused by a virus, and an insect vector — the 

 beet leaf hopper Eutettix tenellus (Baker) — has been demon- 

 strated to be the agent which transmits the virus. The develop- 

 ment of a resistant variety awaited, therefore, more complete 

 understanding of the disease and further perfection of technique 

 in selecting and breeding for disease resistance. In the next decade 

 of the century, L. R. Jones and others of the faculty and grad- 

 uate personnel of the University of Wisconsin would brilliantly 

 control Fusarium disease of cabbage, cabbage yellows so-called, 

 by breeding and selecting plants resistant to this " seriously 

 prevalent " disease. These skillful men obtained by " further 

 hybridization and selection excellent commercial varieties of cab- 

 bage perfectly developed in fields where all the common sorts 

 died from the attacks of Fusarium congliitinans!^ Smith would 

 praise their " beautiful photographs, showing long rows of well- 

 headed and healthy cabbage plants surrounded by thousands of 

 dead and dying ones." -^ For several years Jones's and his co- 

 workers' reports of progress would be among the most important 

 papers presented at meetings of the American Phytopathological 

 Society and published in the society's journal, Phytopathology. 

 Eubanks Carsner, later a student of Jones and prominent as an 

 originator of varieties of sugar beet resistant to curly top,-^ 

 modeled his breeding for disease-resistance after the work of 

 Jones. Carsner's work will be mentioned further later. 



At Cornell University, in coordinate work of the departments 

 of plant pathology and plant breeding at the New York State 

 College of Agriculture, Walter H. Burkholder would explore the 

 incidence of the Mendelian " three and one " ratio in disease 

 resistance and susceptibility, while seeking by selection and hybri- 

 dization to obtain an anthracnose-resistant white marrow bean. 

 Burkholder's accomplishment was accounted by Smith an out- 

 standing event of the half century of American pathology. By 



^^ Technical Bulletin 360: 4, U. S. Dep't of Agric, May, 1933; also U. S. D. A. 

 Bur. PI. Indus. Bull. 122, 1908, 37 p., illus. 



^'' Fifty years of pathology, op. cit., 33,37. 



^'^ Eubanks Carsner,, Curly-top resistance in sugar beets and tests of the resistant 

 variety U. S. No. 1, Tech. Bull. 360, U. S. D. A. May, 1933, 68 pp., illus. 



