LUTHER BURBANK 



The precise result was this: (1) Smooth yellow 

 grains 2,869, or 25.3 per cent; (2) smooth white 

 grains 2,933, or 25.7 per cent; (3) wrinkled yel- 

 low grains 2,798, or 24.5 per cent; (4) wrinkled 

 white grains 2,803, or 24.5 per cent. 



We have seen that the condition of whiteness 

 and the wrinkled condition (due to large sugar 

 content) are recessive traits. Therefore if we 

 plant the wrinkled white kernels we may expect 

 sugar corn, the ears of which will be uniformly of 

 that type. 



But what we wished to secure, it will be re- 

 called, was an ear bearing only yellow wrinkled 

 kernels. There are as many of these as of the 

 others on the ears of the second-generation hy- 

 brids. But they will not all breed true, because 

 yellowness is a dominant factor, and so in a cer- 

 tain number of the yellow kernels the quality of 

 whiteness exists as a recessive trait in hiding, that 

 will reappear in the next generation. 



All the progeny of yellow wrinkled kernels will 

 be wrinkled because the wrinkled condition is re- 

 cessive; but only about one in four of these ker- 

 nels will produce yellow progeny with certainty. 



And no one can tell from mere inspection which 

 of the four is the pure dominant and which the 

 mixed dominant that will have a certain propor- 

 tion of white offspring. 



[38] 



