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Rice yellow mottle virus (RYMV) disease is the leading biotic stress affecting rice (Oryza sativa L.) production in Africa, causing yield losses ranging from 10% to 100%. In Ghana, most of the leading aromatic rice varieties are susceptible to RYMV disease. In this study, two resistant genotypes (Gigante and K150710) were crossed to a leading aromatic variety (CRI-AgraRice), which is susceptible to RYMV, to determine the mode of inheritance of RYMV disease using both Mendelian and quantitative methods. While the Mendelian segregation pattern suggested a single recessive gene is responsible for resistance to RYMVD in Gigante, the quantitative methods indicated that up to two genes could be responsible for RYMVD resistance in the CRI-AgraRice × Gigante cross. Resistance to RYMVD in the AgraRice × Gigante cross was explained by duplicate epistasis. The inheritance of resistance to RYMVD in CRI-AgraRice × K150710 was polygenic, with up to five genes being responsible and with the gene action fitting into an additive-dominance model. Heritability and genetic advance for the two crosses were high, indicating that breeding for resistance to rice yellow mottle virus disease is feasible. [ABSTRACT FROM AUTHOR]