biostudies-literatureZhang Hthe Government of Jiangsu ProvinceNational Natural Science Foundation of ChinaNatural Science Foundation of Jiangsu Province59https://www.ebi.ac.uk/biostudies/studies/S-EPMC9705664biostudies-literatureUnknown15(1)Wild abortive-type cytoplasmic male sterility (WA-type CMS) has been exclusively used in hybrid seed production in indica rice cultivars, and fertility restoration in WA-type CMS is controlled by two major restorer genes, Rf3 and Rf4, through a sporophytic mechanism. However, the genetic mechanism underlying fertility restoration in WA-type CMS in japonica cultivars is poorly understood. In the present study, C418, a leading Chinsurah Boro II- (BT)-type japonica restorer line, showed partial restoration ability in WA-type japonica CMS lines. The 1:1 segregation ratio of partially fertile to sterile plants in a three-cross F₁ population indicated that fertility restoration is controlled by one dominant gene. Gene mapping and sequencing results revealed that the target gene should be Rf4. The Rf4 gene restores fertility through a sporophytic mechanism, but the Rf4 pollen grains show a preferential fertilization in the testcross F₁ plants. Furthermore, Rf4 was confirmed to have only a minor effect on fertility restoration in WA-type japonica CMS lines, and Rf gene dosage effects influenced the fertility restoration of WA-type CMS in japonica rice. The results of our study not only provide valuable insights into the complex genetic mechanisms underlying fertility restoration of WA-type CMS but will also facilitate the efficient utilization of WA-type CMS in japonica rice lines.Rice (New York, N.Y.)The Effects of Rf4 and the Genetic Mechanism Behind Fertility Restoration of Wild Abortive Cytoplasmic Male Sterility (WA-CMS) in Japonica Rice (Oryza sativa ssp. Japonica).PMC970566431771743202111117094Y32072031PL20200431971913PAPD ProgramBK20200927YCSL202104Li XZhang HTang SWan ZLiu QGu MCheng XXu ZZhao XfalseThe Effects of Rf4 and the Genetic Mechanism Behind Fertility Restoration of Wild Abortive Cytoplasmic Male Sterility (WA-CMS) in Japonica Rice (Oryza sativa ssp. Japonica).Wild abortive-type cytoplasmic male sterility (WA-type CMS) has been exclusively used in hybrid seed production in indica rice cultivars, and fertility restoration in WA-type CMS is controlled by two major restorer genes, Rf3 and Rf4, through a sporophytic mechanism. However, the genetic mechanism underlying fertility restoration in WA-type CMS in japonica cultivars is poorly understood. In the present study, C418, a leading Chinsurah Boro II- (BT)-type japonica restorer line, showed partial restoration ability in WA-type japonica CMS lines. The 1:1 segregation ratio of partially fertile to sterile plants in a three-cross F₁ population indicated that fertility restoration is controlled by one dominant gene. Gene mapping and sequencing results revealed that the target gene should be Rf4. The Rf4 gene restores fertility through a sporophytic mechanism, but the Rf4 pollen grains show a preferential fertilization in the testcross F₁ plants. Furthermore, Rf4 was confirmed to have only a minor effect on fertility restoration in WA-type japonica CMS lines, and Rf gene dosage effects influenced the fertility restoration of WA-type CMS in japonica rice. The results of our study not only provide valuable insights into the complex genetic mechanisms underlying fertility restoration of WA-type CMS but will also facilitate the efficient utilization of WA-type CMS in japonica rice lines.2022-01-01T00:00:00Z2022 Nov2025-04-05T15:41:42.412Z2025-04-05T15:41:42.412ZS-EPMC97056643644129610.1186/s12284-022-00605-0