AMMI Analysis for Genotype × Environment Interaction of White Cumin (Trachyspermu mammi L.) Genotypes in Potential Growing Areas of Ethiopia

The experiment was conducted to select the best yielder and widely adaptable white cumin genotypes across different testing environments during the 2012, 2013, 2014, and 2015 main cropping seasons. Nine white cumin genotypes were evaluated in RCBD design using three replications at eleven environments. The combined mean performance recorded a higher mean seed yield from genotype G3 (1,031.3 kg ha-1) followed by genotype G7 (1,011.2 kg ha-1). The AMMI analysis of variance for seed yield showed a highly significant (p<0.01) difference among genotypes, environments, and genotype × environment. The environmental effect accounted for 64.03% of the total variation, whereas the genotype × environment and genotype effect accounted for about 1.65% and 10.27% of total sum squares respectively. The first IPCA captured about 50.4% of genotype × environmental interaction sum square, while the second IPCA explained about 25.2%. The two IPCs cumulatively explained 75.6% of genotype × environmental interaction sum square. Based on ASV scores G7 and G4 have the lowest ASV and they are the most widely stable genotypes across environments. In contrast, genotypes G5 and G1 score relatively the highest ASV and are considered unstable genotypes. E3 scored the least negative IPCA1 values, while environments E5, E8, and E9 scored maximum positive and negative IPCA1 values.