Genotype by trait biplot analysis to study associations and profiles of Ethiopian white lupin (Lupinus albus) landraces

Abstract

Limited information is available on trait relations and profiles of white lupin landraces in tropical growing conditions including Ethiopia. The objectives of this study were to understand the relationships among traits, and to document trait profile of Ethiopian white lupin landraces. As a component of this study, two sets of experiments were conducted. The first comprehensive experiment that consisted of 144 accessions collected from major lupin growing areas of Ethiopia was evaluated at Merawi and the second experiment that consisted of 12 selected accessions was evaluated across six locations. In both experiments, significant variations were observed among the accessions for most studied traits. Higher heritability and genetic advance as percent of mean was observed for grain yield, indicating the possibility of improving this trait through selection. Genotype by trait biplots captured 55% - 66% of the variations due to genotype by trait interactions. Trait association and trait profile biplots were constructed for highland, mid altitude and low land environments, and across all locations. Different patterns of associations and genotype (accession) by trait interactions were observed in different environments. However, genotype by trait biplots consistently indicated that grain yield had positive associations with most of the traits; especially, with number of pods per plant, plant height and seeds per pod. The study identified some accession with desirable performances as good for specific trait and/or trait groups that could be considered as sources of genes for the traits they have best performed. G8 consistently showed higher grain yield, G2 had higher number of branches and higher number of seeds per plant, G7 had more number of pods per plant and larger seed size and G4 produced longer pods. The accessions used in this study were found to be useful sources for genetic variability for future breeding that targets to improve grain yield and other agronomic traits of white lupin in Ethiopia.