Well, maize already have heterotic groups well established. So, if you have a company that is starting a breeding program, it's a good start make a dialel. But in more advanced stages, your groups are defined so you don't need make all this work.

Because the specific combiners in maize are controlling a dominance action, and that is not inherited.

Hi Purushotaman, The best hybrid with the best specific combination of two parents may still not show enough heterosis to be considered for commercial usage if you began your exercise with sub standard parental material. You cannot connect sca with commercial heterosis then. But if your best combination can beat the best check hybrid in heterosis, you would not have had this question. Good luck.