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Question
If we pure-bred tall (dominant) pea plant with pure-bred dwarf (recessive) pea plant we will get pea plants of F1 generation. If we now self-cross the pea plant of F1 generation, then we obtain pea plants of F2 generation.
(a) What do the plants of F2 generation look like?
(b) State the ratio of tall plants to dwarf plants in F2 generation.
(c) State the type of plants not found in F1 generation but appeared in F2 generation, mentioning the reason for the same.
Solution
When a pure breeding tall pea plant is crossed with a pure breeding dwarf pea plant
(a) All the plants in the F1 generation appear tall.
(b) The ratio of tall pea plant to dwarf pea plants is 3 (tall) : 1 (dwarf).
(c) The dwarf plant does not appear in the F1 generation but appears in the F2 generation because the progeny produced in the F1generation were heterozygous (Tt). Hence, when they were selfed for obtaining the F2 generation, dwarf plants were also formed in the progeny. The cross involved in as follows
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