Agronomy and Horticulture, Department of
Plant and Soil Sciences eLibrary
Resistance Genetics: Origin of Resistant Alleles
Document Type
Learning Object
Date of this Version
11-2025
Citation
Plant and Soil Sciences eLibrary (PASSeL) Lessons
Abstract
Overview
Overuse and reliance on pesticides to control agricultural pests has caused pest populations to evolve due to the application of artificial selection. Individuals with a higher tolerance for pesticides survive to reproduce – increasing resistant individuals that will eventually outnumber the ones that are controllable.
Resistance Genetics is a set of 4 lessons that teach about the genetic basis of pesticide resistance. These lessons can be used together or as separate lessons.
- Trait Expression
- Genotypic Inheritance and Connection to Phenotype
- Origin of Resistant Alleles
- Selecting Genes for Resistance - Evolution of Resistance to Pesticides in Populations
This is the Origin of Resistant Alleles lesson.
The first Resistance Genetics lesson on Trait Expression described how genes are expressed by providing the cell protein coding instructions. This Resistance Genetics lesson on Genotype and Phenotype focused on the inheritance of genes and explained the occurrence of phenotype variation in families.
This lesson on the origin of resistant alleles describes how and where pesticide resistance in a population begins.
Learning Objectives
By the end of this module, each student should be able to:
- Identify genetic and environmental influences on phenotype,
- List environmental factors that vary in a growing environment and can influence an organisms’ phenotype,
- Describe how new alleles can enter a gene pool from mutation or migration,
- Predict the impact of mutation and migration on the rate of change in a gene pool,
- Compare the effectiveness of pest resistance management when fitness costs of resistance alleles are or are not a factor.
Comments
The materials for these modules were developed with support from the United States Department of Agriculture National Institute of Food and Agriculture National Needs Fellowship Program, Award No. 2016-38420-25297. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the U.S. Department of Agriculture.