LUTHER BURBANK 



of wheat that are immune to the pest; but unfor- 

 tunately these produce a very poor quality of 

 grain. 



Professor Biffin found that susceptibility and 

 immunity to rust constitute a pair of unit char- 

 acters, in which susceptibility is prepotent or 

 dominant. 



When he crossed the susceptible grain with 

 the immune one, he therefore produced an entire 

 generation of susceptible grain. 



His experiment had seemingly gone backward, 

 quite as in the case of my first generation of white 

 blackberries. 



But in the ensuing generation the recessive 

 character of immunity reasserted itself; and, 

 combined with this desired character, in a certain 

 proportion of the progeny, there appeared the 

 other desired quality of a good head of grain of 

 fine quality. 



So by the application of this principle of the 

 segregation and recombination of unit characters 

 Professor Biffin produced a new race of wheat 

 in two or three generations, and this new race 

 of wheat breeds true. 



We shall see this principle illustrated over 

 and over in connection with the long series of 

 my plant experiments. 



In case of the wheat, as in that of my white 



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