Molecular biology of wheat cereal

The evolution of the different types of wheat was mainly by chance by occurred with a little help from human ancestors who choose to cultivate seed from the best plants they could find in nature.

By the best what they were looking for was the variety that would give them the highest yields in their climate and on their land.

The search for the best variety is still going, but most of the wheat varieties grown today exist as the direct results of man’s intervention.

They are the results of thousands focused breeding trial in which the superior varieties are selected out of the existing genetic pool (much as our ancestors did), but these varieties are then deliberately developed into thousands of modern hybrids by using just three species (T. aestivum, T. sphaeroccum, and T. compactum).

These three species are easily “intercrossed” to form hybrids. Hybridization occurs when two varieties with desired characteristics are deliberately “chosen” to be the parents of a new variety rather than “intercrossed” by chance.

To ensure that the correct genetic combination is achieved, the breeder first removes the unripe anthers (pollen-containing organs) from one parent plant.

Next the plant s “contained” to prevent pollination from any undesirable source. As soon as the stigmas are ready to be pollinated, the breeder introduces pollen from the desired second “parent” plant.

The seed derived from this first generation hybrid are all identical, but subsequent generations will exhibit a range of characteristics from which seed the desired characteristics can be selected.

Once selected, they can be “amplified” through successive plantings into a pure genetic line.
Molecular biology of wheat cereal