Mendel's Selection of True Breeding Plant Varieties

Mendel, the father of genetics, conducted experiments on pea plants to understand the inheritance of traits. He selected 14 true breeding plant varieties, as pairs which were similar except for one character with a contrasting trait. Let's understand this in detail.

True Breeding Plant Varieties

True breeding plant varieties are those that produce offspring with the same traits as their parents. They are homozygous for a particular trait, i.e., they carry two identical alleles for a gene controlling a particular trait.

Character and Trait

A character is a heritable feature that varies among individuals. For example, flower color is a character in pea plants. A trait is a variant of a character. For example, purple and white are two traits of the flower color character in pea plants.

Contrasting Traits

Mendel selected plant varieties with contrasting traits, i.e., varieties that differed in only one character. For example, he selected a variety with purple flowers and another with white flowers. These two varieties differ only in the flower color character.

14 Pairs of True Breeding Plant Varieties

Mendel selected 14 pairs of true breeding plant varieties with contrasting traits for seven characters:

1. Flower color (purple and white)
2. Flower position (axial and terminal)
3. Seed color (yellow and green)
4. Seed shape (round and wrinkled)
5. Pod color (green and yellow)
6. Pod shape (inflated and constricted)
7. Stem length (long and short)

Importance of Mendel's Selection

Mendel's selection of true breeding plant varieties with contrasting traits was crucial in his experiments. It allowed him to observe the inheritance patterns of traits and formulate his laws of inheritance. His laws of inheritance laid the foundation for modern genetics and have helped in the understanding of genetic disorders and gene therapy.