Interpret a QQE biplot
A QQE biplot has the same interpretability as a GGE biplot, except that genotypes are replaced by genetic markers or QTL. All enabled functions are applicable to a QQE biplot, but the following may be more general:
- Examine the effect of each marker on the trait of interest (i.e., the associations of the marker with the target trait) in various environments.
- Identify the most important markers in each environment.
- Examine the mean effect and consistency of a marker on the trait across the environments.
- Identify markers with relatively consistent effect across environments (QTL represented by these markers are often called QTL for genotype main effect).
- Identify markers that have contrasting effects in different environments and thereby are responsible for the observed GE interaction for the target trait.
- Examine the grouping of environments (mega-environment classification) based on the QQE pattern, which may help develop a strategy to uitlize the GE through marker assisted selection.
Here is a complete example of QQE biplot analysis.