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THE SWEDISH GENETIC INSTITUTE IN AKARP 



With regard to the investigations into the mode of inheritance of genetic 

 characters ecological characters are now especially followed up. With respect to 

 the annual*biennial character in wheat distinct multiple or polymeric genes are 

 met with here as in numerous other characters. Also in wild plants a number of 



adaptive genetic charac* 

 ters are studied, charac* 

 ters adapted to climate 

 as well as to soil (the 

 latter mostly studied by 

 Mr. TURESSON). 



The study of muta* 

 tions involves also the 

 important point, wheth* 

 er or not the mutations 

 S may be regarded to play 

 any role in evolution. 

 For this purpose large 



The Swedish genetic institute in Akarp. 



cultures of pure lines of autogamic cereals are made in order to see if in a Men* 

 delian factor pair, A a, the mutative change is possible in both directions, 

 and whether, and to which measure, reversible mutations arise. Another series 

 of investigations concerns small mutations of quantitative characters (wheat, beans). 

 Special attention is also paid to the question of the origin of mutations, which 

 may be of value in the practical plant breeding. 



In addition to the purely theoretical work practical plant breeding plays an 

 important role at the institute. About 2 h of the ground is occupied by plant 

 breeding plots, while the remaining ] /3 belongs to the purely theoretical work. 

 Hitherto the plant breeding embraces only cereals (winter wheat, summer wheat, 

 barley, rye and to some little extent Indian corn). 



The writer fulfils his former breeding* and combination*work begun in Svalof 

 with regard to wheat. In the summeMemperate, halfemaritime part of Sweden the 

 winter wheat breeding is highly favorized as compared with a continental, summer* 

 hot climate, as but little regard has to be taken to early ripening. In the northern 

 part of Sweden, on the contrary, the importance of winter hardiness increases 

 with the latitude. The main point is therefore to combine through crossing high 

 yielding*power with sufficient winter hardiness. The best high*yielding West 

 European wheats yield, when not damaged during the winter, about 50. % more 

 than the old winterhardy Swedish wheat. However, these wheats are in the most 

 winters (excepting the rare very milde ones) not at all winterhardy enough and 

 yield therefore only little. Thus through combining sufficient winter hardiness 

 with high yielding power an increase in mean yielding=power of 50 % should be 

 reached a very important economic gain. As winter hardiness, yielding*power 

 and other characters of practical interest as, for instance, straw stiffness, hereditary 

 resistance against diseases (yellow rust and others) are characters which segregate 

 in a very complex manner giving rise to many intermediate (or in other cases 

 transgressive) stages, the aim is not to be gained at once, that is, through one 

 cross only, followed by successive selections. A repeated and long continued 



