Genetics & Breeding
Genotype, Phenotype & Environment
A genotype is an organism's genetic constitution; phenotype is the observed result of genotype interacting with development and environment. Breeding decisions become stronger when traits are measured across replicated environments rather than assumed to be purely genetic.
Key concepts
- The same genotype can express differently across environments
- Different genotypes can respond differently to the same environment
- Trait expression can change with developmental stage
- Selection should distinguish repeatable genetic differences from temporary environmental effects
What to measure or observe
- Use consistent trait definitions
- Record environment with phenotype scores
- Repeat observations across time or locations when possible
- Keep plant identity connected to every measurement
Common mistakes
- Calling every observed difference genetic
- Selecting from one stressed environment without context
- Changing scoring criteria during a population evaluation
- Losing plant identity after harvest
Visuals this lesson still needs
- Genotype-environment-phenotype triangle
- Same genotype/different environment comparison
- Trait scoring workflow
- Selection evidence map