Structuring genotype × environment interaction — an overview

Abstract

The phenotype of an individual is determined by both the genotype and environment. Farmers and scientists aim to determine a superior genotype over a wide range of environmental conditions but also over years. The basic cause of differences between genotypes in their yield stability is when these two effects are not only additive, i.e. when genotype × environment interaction (GEI) is present in the data. Multi-location trials play an important role in plant breeding and agronomic research. The data from such trials have three main points: (i) to accurately estimate and predict yield based on limited experimental data; (ii) to determine yield stability and the pattern of response of genotypes across environments; and (iii) to provide reliable guidance for selecting the best genotypes or agronomic treatments for planting in future years and at new sites (Crossa, 1990). The purpose of the present paper is (i) to describe various multivariate statistical methods for analyzing interactions in general and GEI in particular, and (ii) to present a selected bibliography of 142 references to previous work.