Mendel selected 14 true breeding pea plant varieties, as pairs which were similar except for one character with contrasting traits.
S.No
Character
Contrasting traits
Chromosome number
1.
Stem height
Tall / dwarf
4
2.
Flower position
Axial/terminal
4
3.
Flower colour
Violet/white
1
4.
Pod shape
Inflated/constricted
4
5.
Pod colour
Green/yellow
5
6.
Seed colour
Yellow/Green
1
7.
Seed shape
Round/wrinkled
7
In this 1 character is related to stem height, 2 characters are related to flower, 2 characters related to pod, 2 characters are related to seed. So, the correct option is ‘Pod length’.