Corn Breeding: Mass Selection - Objectives and Introduction

This is the fourth in a series of lessons specifically designed to instruct individuals without any formal training in genetics or statistics about the science of corn breeding. Individuals with formal training in genetics or statistics but without any training in plant breeding also may benefit from taking these lessons.

Mass selection could be called appropriately the granddaddy of all plant selection methods, because farmers of many different cultures have used it for centuries to improve many crops. Specifically, mass selection is a breeding method where the decision to select a plant as a parent of the next generation is based on the performance of that plant. In this lesson, advantages and disadvantages of mass selection will be discussed, using examples from corn breeding.

Objectives

At the completion of this lesson you will be able to

• list the key attributes of mass selection,
• discuss which type of traits are best suited to modification by mass selection,
• use the formula known as the breeders’ equation to predict the genetic gain that occurs from mass selection,
• define selection differential,
• discuss how the selection differential can be increased and what problems can arise from increasing the selection differential, and 
• list four ways to minimize the amount of inbreeding that occurs during selection.