5.10 Breeding Plants

• 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 
• 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 . The farmer will then 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 causes the increase in yield. 

This is an example of selective breeding.