Question

A snapdragon plant that bred true for white petals was crossed with a plant that bred true for purple petals, and all the F1 had white petals. The F1 were selfed. Among the F2, three phenotypes were seen: solid purple: 61 white: 240 spotted-purple 19. If two spotted-purple plants from the F2 generation were crossed, what would be the phenotypic ratio of the offspring

Answer 1

Step-by-step explanation:

I would propose the ratio is 12 white : 3 yellow : 1 spotted. You can check this using Chi square test.

So two gene pairs are involved in this trait.

W : allele for white

Y : allele for yellow

y : allele for spotted

W is dominant epistatic to Y and y

P: white (WWyy) >< yellow (wwYY)

F1: all white (WwYy)

F2: 9 W-Y- (white) : 3 W-yy (white) : 3 wwY- (yellow) : 1 wwyy