102 



GENETICS IN SWEDEN 



"1 



Difficulties in obtaining suitable experimental ground hampered and limited 

 the work of Lidforss. He succeded at last to arrange the matter but died after 

 short time, working to the last minute. 



Lidforss represents the searcher, the problem raiser in the history of Swedish 

 genetics; he is not in the same degree the solver of problems but his logical in» 



telligence, his enthusiasm and great learning gave 

 a mighty impetus to the study of genetics in 

 Sweden. 



While Lidforss spent his time at the Uni» 

 versity of Lund struggling against practical ex< 

 perimental difficulties one of the most important 

 genetical analysis hitherto made was going on 

 at the plant breeding institute in Svalov. Nobody 

 knew anything about this work before it was 

 done and published. It was H. Nilsson^Ehle 

 who in 1908—1909 presented the results of his 

 investigations of polymeric factors in wheat and 

 oats. An analysis of weight had now been worked 

 out in Sweden. The great importance of this 

 analysis with regard to the interpretation of 

 quantitative variation, acclimatization, and other 

 questions was at once realized. The cogency of 

 his analysis showed the potentiality of the young 

 Mendelian science, and, therefore, stimulated 

 and spurred the study of genetics among Swedish 

 scientists. It also showed that the intensive study of genetics required special and 

 good experimental working conditions. These are mainly of two kinds, sufficient 

 ground and sufficient assistance, and such requirements are better fulfilled at the 

 plant breeding institutes than at the universities. Most of the Swedish geneticists 

 are therefore engaged at the plant breeding stations. The material experimented 

 upon is also mainly cultivated plants. 



The valuable contribution to genetics made by Nilsson^Ehle through his 

 analysis of polymery in 1909 was renewed a few years after when his extensive 

 work on the inheritance of quantitative characters appeared. This work rests upon 

 the polymery analysis and represents a further building up of the theory. Since 

 then the mutation phenomenon has mainly occupied his interest. He has investig^ 

 ated expecially three groups of mutants, viz. chlorophyll variants in barley, and 

 fatuoid variants in oats and speltoid ones in wheats. His work on the speltoid 

 mutants in wheat, where segregations is strongly disturbed by many complications 

 (coupling, elimination of gametes, partial heterogamy), is especially rich in fresh 

 suggestions and new ideas. Another study dealing with the resistance of barley 

 towards the attacks of the nematode Heterodera Schachti is important also from 

 a practical point of view; the character shows monohybrid segregation, which is 

 a rare case of segregation among resistance«characters. 



A genetical study started already in pre«Mendelian time, or about 1890, has 

 been made by Hans Tedin in Svalov dealing with peas, Mendel's classical experis 



Dr. Hans Tedin. 



