206 FIELD CROPS FOR THE COTTON-BELT 



all of the yellow kernels produced on such an ear, one- 

 third will be pure yellow and two-thirds will be hybrid as 

 regards color. All of the white kernels will be pure as re- 

 gards color. 



252. Dominant qualities in corn hybrids. We have 

 seen that according to Mendel's law opposite qualities of 

 parents are not blended in the hybrid, but are inherited 

 separately, the individual descendants showing only one 

 of these characters. According to this law the dominant 

 character shows in the first-generation hybrid to the ex- 

 clusion of the other. The recessive character reappears in 

 the second and subsequent generations in one-fourth of the 

 progeny, and thereafter remains pure. 



Investigation has shown the following characters in 

 corn to be dominant over their opposites: Yellow endo- 

 sperm 'dominant over white endosperm; starch endosperm 

 dominant over sweet endosperm; red pericarp dominant 

 over colorless pericarp; flint quality of grains dominant 

 over dent; flint quality of grains dominant over sweet; 

 dent quality of grains dominant over sweet; blue aleurone 

 dominant over colorless aleurone; podded kernels dom- 

 inant oyer naked kernels. 



253. Effects of inbreeding. Experiments conducted 

 by Shull, 1 East, 2 Montgomery, 3 and Halsted 4 prove con- 

 clusively that the immediate effect of inbreeding corn is to 

 decrease the yield. These results indicate that continued 

 inbreeding may in some cases produce absolute sterility. 

 Corn is sometimes self-fertilized for two or three genera- 

 tions by breeders with the object of producing a pure type. 



1 Ann. Rpt. Amer. Breeders Assoc., Vol. VI, 63-72, 1900. 



2 Conn. Agr. Exp. Sta., Bui. 168, 1911. 



3 Nebr. Agr. Exp. Sta., Ann. Rpt. 1912, 183. 



4 N. J. Agr. Exp. Sta., Bui. 170. 



