ABSTRACT
GGE refers to genotype main effect (G) plus genotype-by-environment interaction (GE). It is the part of the variation that is relevant to cultivar evaluation. Included in this chapter are: 1) the general formula for a GGE biplot, 2) two models (regression vs. singular value decomposition) for generating a GGE biplot, 3) three methods of data transformation for generating a GGE biplot, 4) four methods of singular value partitioning between the genotypic and environmental scores, and 5) a step-by-step instruction to construct a GGE biplot using SAS and Microsoft Office software. We trust the reader will realize at the conclusion of this chapter that generating a biplot is just the beginning, rather than the end, of biplot analysis.
