I need help with the image (phenotypes and genotypes).

See the answer below

Explanation:

1. Only one phenotype is present in the F1 generation offspring. Since tallness was dominant over shortness, all the offspring in the F1 generation appeared tall.

2. Two phenotypes are present in the F2 generation - 9 tall and 3 short. The short trait reappeared at the F2 generation.

3. The genotype of the F1 offspring would be heterozygous. Assuming the purebred tall is AA and the purebred short is aa:

     AA   x   aa

  Aa   Aa   Aa   Aa

All the F1 offspring will appear tall and their genotypes would be heterozygous.

4. Assuming that the allele for height is denoted with A (a), the genotype of the purebred tall plant would be AA.

5. In a similia vein, the genotype of the purebred short plant would be aa.