194 THE SMALL GRAINS 



a selection from early Gothland. It has medium coarse 

 straw and long, well-filled white kernels. It yields well 

 and has been grown rather widely. 



198. Work of Nilsson at Svalof. The center of pure- 

 line selection work in recent years has been at the Swedish 

 experiment station at Svalof. At first only mass selec- 

 tion was practiced. When Hjalmar Nilsson became 

 Director, he had already noted the regularity with which 

 many different botanical types appeared each year. In 

 1891, it was noted further that, in 200 types or groups 

 of winter wheat, sorted out of a large number of spike 

 selections, while many of the types included many in- 

 dividuals, in a number of cases there were forms with no 

 duplicates. Each of these forms therefore represented a 

 group alone. These groups were planted in separate 

 plats and only by accident in studying the results in the 

 following harvest was it discovered that of all the hun- 

 dreds of cultures only those few which came from a 

 single spike or plant produced a uniform progeny. It 

 appeared evident therefore that the quickest way, if not 

 the only way, to obtain a uniform sort was to begin with 

 a single plant. Ever since, the unit of improvement at 

 Svalof has been the single plant instead of the group. 

 Later on it was learned further that different types are 

 not to be distinguished always by visible characters ; 

 that is, there are physiological as well as morphological 

 types. 1 



1 About the year 1900 the administrative duties of Nils- 

 son became so heavy that the work with wheat and oats, his 

 specialty to that time, was given entirely to H. Nilsson- 

 Ehle, who remains in charge of it. At the same time the bar- 

 ley work was assigned to Hans Tedin. Later rye was added 

 to the list of subjects, of which Erik Ljung is now specialist in 

 charge. 



