The Gene Pool; Equilibrium Factors 



211 



INBRED A INBRED B 



INBRED C INBRED D 



SINGLE CROSS 

 CxD 



SINGLE CROSS 

 AxB 



ffll J DOUBLE CRO 



yjri (AxB)x(CxD 



CROSS 



) 



figure 15-7. The production of commercial hybrid 

 corn by the "double cross" breeding procedure. 



