A green-stemmed rose plant denoted by GG and a brown-stemmed rose plant denoted by gg is allowed to undergo a cross with each other.
(a) List your observations regarding (i) the Colour of the stem in their F1 progeny
(ii) Percentage of brown stemmed plants in F2 progeny if plants are self-pollinated.
(iii) Ratio of GG and Gg in the F2 progeny.
(b) Based on the findings of this cross, what conclusion can be drawn? (AI 2020)

(a) (i) Colour of the stem in F1 progeny

The colour in the F₁ progeny is green stemmed as green stem colour is dominant.

(ii) F₁ progeny on self pollination

F₂ generation Green stemmed: Brown stemmed 3;1 It means 25% of F₂ progeny are brown stemmed rose plant.

(iii) Ratio of GG and Gg in F₂ progeny
The genotype of F₂ progeny – GG : Gg
Ratio = 1 : 2

(b) This cross is monohybrid. This shows that in the F1 generation, only one dominant feature shows itself out of two contrasting traits, and the trait that does not show itself is recessive. Both features are present in the F1 plants’ offspring after selfing but in a fixed ratio.