Kosuke Kuwabara

1 Introduction Most commercial vegetables and field crops are F1 hybrids because they produce a significant increase in crop yield and provide stability in food production (Duvick 1999). F1 hybrid breeding has long been used for tomatoes (Solanum lycopersicum), one of the most widely cultivated and consumed vegetables worldwide. However, the considerable amount of labour and the maintenance of high seed purity has been a major issue in hybrid seed production (Priyadarsini et al. 2025).

Abstract Cytoplasmic male sterility (CMS) and restorer of fertility (Rf) are important traits in F1 hybrid breeding. However, the CMS/Rf system has not been used in tomatoes because of the limited resources of Rf lines. In this study, we performed mutagenesis in tomato CMS seeds and successfully obtained 13 suppressor mutants with pollen fertility.