MAIZE BREEDING 



185 



TABLES XXXIX. SUMMARY OF INHERITANCE OF ENDOSPERM CHARACTERS 



OF MAIZE 



Reciprocal crosses between flour and flint showed no immediate 

 effect of cross-pollination. The ears, however, of the FI plants 

 showed a distinct segregation into flour and flint seeds in a 1 : 1 

 ratio. Later generations showed that the results were most 

 easily explained on the cumulative factor basis. If a soft flour 

 variety was pollinated by a flint race, the endosperm would con- 

 tain two factors for soft flour, SS, and one for flint condition, 

 F, or SSF. The reciprocal cross would be FFS. If two factors, 

 FF or SS, are completely dominant over one factor, S or F, 

 respectively, there would be no immediate, effect of cross-polli- 

 nation and the segregation on FI ears would be in a 1:1 ratio. 

 Dents crossed with flour races give a very similar result, but the 

 seeds are not so easily distinguished by inspection. Reciprocal 

 crosses between pop and flour races show no immediate effect of 

 pollination with complex segregation on the ears of FI plants. 

 Pure flour and pop forms may be obtained in later generations, 

 but the results cannot be explained by a single factor difference. 

 With the hypothesis that pop and flour corns differ by two or 

 more main factors and with each factor behaving in a some- 



