Pattern Analysis of Genotype Adaptation and Genotype x Environment Interactions in the Uniform Peanut Performance Tests1

Abstract

Abstract Genotype x environment (g x e) interactions can confound comparisons among peanut (Arachis hypogaea L.) genotypes in multi-environment genotype trials. Herein g x e interactions in two data sets constructed from the Uniform Peanut Performance Tests (UPPT) over the period 1973–1978 were examined. Numerical classification and ordination techniques were used to examine genotype adaptation and environmental groupings. Because of the harvest strategy adopted in specific trials, maturity differences among genotypes may have influenced genotype yields and rankings in these trials. For example in trials harvested 151–176 days after planting, Early Bunch yielded 951 kg ha-1 less than the average of Florunner, Tifrun and UF 714021. Conversely in trials harvested 129–141 days after planting, Early Bunch was 700 kg ha-1 higher yielding than the average of Florunner, Tifrun and UF 714021. Our results suggest that entries in UPPT trials be harvested in order of their maturities where such maturity differences are known. In any year, performance of new lines should be compared jointly with that of a number of standard genotypes as performance of any one standard may not be indicative of its long term average. There was a degree of regional adaptation of certain genotypes in that, relative to other genotypes, Florigiant performed poorly and Florunner well in southeastern United States environments. However an environmental classification based on g x e interaction effects indicated that, over all genotypes, there were no temporal or closely related regional groups of environments with similar g x e interactions. No evidence was found that genotypes from different breeding programs had substantially different environmental adaptation responses.