5.10 Breeding Plants

Understand that plants with desired characteristics can be developed by selective breeding

The number of rice grain per rice is under the control of genes. The farmer wants to increase the number of rice grain per plant to increase the yield. 

Some plants have 6 grains per stem, while others have 8 and 10 grains per stem (variety in number). 

The farmer's decision is to harvest the grains with 6 and 8 grains, but will use those with 10 grains for planting. 

In the next generation of rice, the grains increase to 8-10-12. And so the farmer will harvest those with 8 and 10 grains, but selective those with 12 grains for planting and breeding.

In this way, the number of grains of rice which are found on  these plants gradually increases. This means increase in yield. 

This is an example of selective breeding.

It can be applied to most characteristics of the plant.