In many of the crops it is noted one or the other colour of the fruit is considered as a dominant character. In many of the crops masking or co- dominant character is also noted. How it is evaluated or verified?
Well you can try a conventional breeding strategy of crossing the plant with another one say white. If the next progeny remains red you can say it is a dominant gene. Or you can check the SSR responsible for it and start genotyping all the progenies.