GENOTYPE BY ENVIRONMENT INTERACTION AND GRAIN YIELD STABILITY OF ETHIOPIAN WHITE LUPIN (LUPINUS ALBUS L.) LANDRACES

Abstract

SUMMARYGenotype by environment interaction is a common phenomenon in crop production and remains an important issue in genotype evaluation and recommendation. However, no detailed multi-environment evaluation of Ethiopian white lupin has been undertaken so far. Thus, this study was undertaken with the objectives to evaluate the performance and stability of white lupin landraces in six locations; and characterize white lupin growing environments in Ethiopia. Twelve white lupin landrace collections of Ethiopia were evaluated across six different locations in Ethiopia during the 2014/15 main growing season using a randomized complete block design with four replications. The genotype main effect plus genotype by environment interaction (GGE) biplots analysis was used to visualize the patterns of the interaction components. The results depicted that the tested landraces had differential performances across locations implying the presence of crossover interaction. The first two principal components (PC1 = 41.6% and PC2 = 21.8%) of the GGE explained 63.4% of the GGE sum of squares. All test locations were found to be representative with different degrees of reliability whereby Finote Selam and Dibate were found to be most representative. In addition, all test locations, except Mandura and Injibara, had generally similar and good discriminating power. Finote Selam and Dibate were found to be the most representative and discriminating environments and are characterized as most desirable test locations for white lupin improvement in northwestern Ethiopia. G2 was found to be the highest yielding and most stable landrace across the test environments, and hence identified as most desirable genotype recommended for production.