LUTHER BURBANK 



breed true; and, what is perhaps equally impor- 

 tant, to eliminate the impure types that would not 

 breed true. 



DOMINANT AND RECESSIVE CHARACTERS 



It will be of interest to note a few characters 

 that Professor Biff en particularly studied and the 

 groups into which they fall. 



As to characters that show the phenomena of 

 pure dominance and recessiveness, the following 

 among others were clearly revealed: Beardless 

 ears of grain are dominant to the bearded ears; 

 keeled glumes to round glumes; lax ears to com- 

 pact ears; red chaff to white chaff; red grain to 

 white grain; thick and hollow stem to thin and 

 solid stem; rough leaf surface to smooth leaf sur- 

 face; bristles on the stem to a smooth stem; hard, 

 translucent endosperm (central grain substance) 

 to soft opaque endosperm; and, finally, suscepti- 

 bility to the attacks of yellow rust was dominant 

 to immunity to yellow rust. 



This implies, as the reader is aware, that in 

 each case of those just listed, when two plants rep- 

 resented by the opposite characters are crossed, 

 the offspring will show the first-named character 

 to the exclusion of the other in the first genera- 

 tion, but the excluded character will reappear in 

 one fourth of the offspring of the second genera- 

 tion. 



[60] 



