in an investigation snapdragon plants with broad leaves were crossed with the plants with narrow (N). The f1 protogyny had intermediate leaf breadth in f1 generation.
a) Give a reason for intermediate leaf breadth in f1 generation.
b) If the plants in the f1 generation were selfed state the genotypic and phenotypic ratio of the f2 generation. Use a punnet square
a) The intermediate leaf breadth in the F1 generation is likely due to incomplete dominance of the broad and narrow leaf traits. In this case, the alleles for broad leaves (B) and narrow leaves (N) are neither dominant nor recessive to each other, resulting in an intermediate phenotype in the heterozygous plants.
b) If the plants in the F1 generation were selfed, the genotypic ratio of the F2 generation would be 1 BB : 2 BN : 1 NN, and the phenotypic ratio would be 3 broad leaves : 1 narrow leaf.
Punnet square:
B N
B BB BN
N BN NN