1. GGE Biplot
Rebecca Nolan

2. What is GGE biplot? A software program designed by Weikai Yan
GGE stands for Genotype main effect and Genotype X Environment interaction
Scatter plot that plots both genotypes and environments in the same plot

3. What can it do? Show patterns in the data
Identify the best or worst cultivars in certain environments
Show relationships among environments
Mega environments
Show discriminating ability of an environment

4. What can’t it do? Show statistical significance Everything is relative
Units mean nothing
Take interesting pattern and go back to the original data to perform statistical analysis

5. What types of data can GGE biplot be use for?
Genotype by environment data on a single trait – ex. Yield
Genotype by trait two-way data- ex yield, height, and maturity
Diallel cross data – ex identify good combining ability
In fact any two-way matrix data can be done

6. How does it work? Principal component analysis is run on the data
PC1 by PC2 is plotted
Can look at other PCs
PC1 represents mostly genotype effect
PC2 represents mostly GXE interaction

7. How does it work? cont. What about the environment main effect?
Removed before principal component analysis is done
Expect there to be an effect, but it is not important from a breeder’s perspective

13. What can it do? Show patterns in the data
Identify the best or worst cultivars in certain environments
Show relationships among environments
Mega environments
Show discriminating ability of an environment

14. Where can I get the program?
From Weikai Yan
Website –
Crop Sci 41:
Crop Sci 40: