The researchers used the AMMI model to study how different rice genotypes perform in various environments in Iran. They tested seven rice genotypes over three years and found that the genotype-environment interaction significantly affected grain yield. Some genotypes performed better in certain environments than others. The AMMI model showed that certain genotypes were more stable and had higher grain yield. Overall, the study showed that the interaction between genotype and environment plays a crucial role in determining rice yield variation in Iran.