Question

Genotype of dominant plant can be determined by

• A. Pedigree analysis
• B. Back cross
• C. Test cross
• D. Dihybrid cross

Hint:

A test cross is a simple yet effective method to determine the genotype of a dominant organism.

Answer 1

The Correct Option is C

To determine the genotype of a dominant plant, a \textit{test cross} is commonly used. A test cross involves crossing the dominant plant with a homozygous recessive plant. By analyzing the offspring, the genotype of the dominant parent can be inferred.
(1) Test Cross:
- A test cross is used to determine whether a plant showing a dominant trait is homozygous or heterozygous.
- The dominant plant is crossed with a plant that is homozygous recessive for the same trait.
- If any offspring show the recessive trait, the dominant plant must be heterozygous. If all offspring show the dominant trait, the dominant parent is likely homozygous.

(2) Why Other Options Are Incorrect:
- Pedigree analysis helps trace genetic traits through generations but does not directly determine the genotype of an individual.
- Back cross is a cross between an offspring and one of its parents, and while it can be useful in certain situations, it doesn't specifically determine the genotype of a dominant plant.
- Dihybrid cross involves the inheritance of two traits simultaneously, which is not necessary to determine the genotype of a single dominant trait.

Conclusion: The most suitable method to determine the genotype of a dominant plant is the test cross, as it directly reveals whether the dominant plant is homozygous or heterozygous.