Evaluation of Genotype × Environment Interaction for Seed Yield of Sunflower Hybrids using GGE Biplot Method

The sunflower is one of the most important oilseed plants in the world and its oil has nutritional and high economic value. Identification and selection of high-yielding genotypes with desirable characteristics are especially important in this plant. Evaluating sunflower genotypes under different environmental conditions would be useful to identify genotypes with high stability and yield potential. Therefore, this study was conducted to the selection of the best sunflower hybrids.

In this study, 24 new sunflower hybrids along with Golsa cultivar were evaluated in a simple lattice design with two replications in four experimental field stations (Karaj, Boroujerd, Shahroud, and Gorgan) during the 2020 cropping season. GGE biplot statistical method (genotype effect + genotype × environment interaction) was used to study the stability of genotypes in the studied environments.

Results of combined analysis of variance indicated that the effects of environments, genotypes, and genotype × environment interaction were significant, suggesting that the genotypes responded differently in the studied environment conditions. So, there was the possibility of stability analysis. Results of stability analysis using the GGE biplot method indicated that the two first and second principal components of the GGE biplot explained 67.7% of the total seed yield variation. Based on the polygon view of biplot, the genotype G13 in shahroud environment, the genotype G6 in Karaj and boroujerd environments, and genotypes G5 and G19 in Gorgan environment were superior genotypes with the high specific adaptation. Based on the hypothetical ideal genotype biplot, the genotypes G6, G14, G3, and G4 were better than the other genotypes for seed yield and stability and had the high general adaptation to all environments. Also, the results showed that all environments had high discriminating ability so that could able to show differences between genotypes. The Boroujerd environment was the nearest environment to the ideal environment that had the highest discriminating ability and representativeness.

Consequently, the genotypes G6, G14, G3, and G4 were better than the other genotypes for seed yield and stability. Therefore, these genotypes can be used for further testing, including adaptation tests.