title: Multiple CMS-restorer gene polymorphism in gynodioecious Plantago coronopus.
abstract: The mode of inheritance of the male sterility trait is crucial for understanding the evolutionary dynamics of the sexual system gynodioecy, which is the co-occurrence of female and hermaphrodite plants in natural populations. Both cytoplasmic (CMS) and nuclear (restorer) genes are known to be involved. Theoretical models usually assume a limited number of CMS genes with each a single restorer gene, while reality is more complex. In this study, it is shown that in the gynodioecious species Plantago coronopus two new CMS-restorer polymorphisms exist in addition to the two that were already known, which means four CMS-restorer systems at the species level. Furthermore, three CMS types were shown to co-occur within a single population. All new CMS types showed a multilocus system for male fertility restoration, in which both recessive and dominant restorer alleles occur. Our finding of more than two co-occurring CMS-restorer systems each with multiple restorer genes raises the question how this complex of male sterility systems is maintained in natural populations.
authors.affiliation: Netherlands Institute of Ecology, Center for Terrestrial Ecology, PO Box 40, 6666 ZG Heteren, The Netherlands. jvandamme@nioo.knaw.nl
authors.forename: J M M
authors.initials: JM
authors.lastname: van Damme
authors.forename: M P J
authors.initials: MP
authors.lastname: Hundscheid
authors.forename: S
authors.initials: S
authors.lastname: Ivanovic
authors.forename: H P
authors.initials: HP
authors.lastname: Koelewijn
mesh_terms: D003433:Crosses, Genetic; D003593:Cytoplasm / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D007494:Ireland; D009426:Netherlands; D010943:Plantago / Q000235:genetics*; D011110:Polymorphism, Genetic; D012098:Reproduction / Q000235:genetics; D012737:Sex Factors; D012744:Sex Ratio