TESTING MODELS OF SEX RATIO EVOLUTION IN A GYNODIOECIOUS PLANT: FEMALE FREQUENCY COVARIES WITH THE COST OF MALE FERTILITY RESTORATION

摘要: In many gynodioecious species, cytoplasmic male sterility genes (CMS) and nuclear fertility restorers (Rf) jointly determine whether a plant is female or hermaphrodite. Equilibrium models of cytonuclear gynodioecy, which describe the effect natural selection within populations on sex ratio, predict that frequency females in population will primarily depend cost restoration, negative pleiotropic Rf alleles hermaphrodite fitness. Specifically, when restoration higher, at equilibrium predicted to be higher. To test this prediction, we estimated variation across 26 Lobelia siphilitica, species can have effects pollen viability. We found L. siphilitica with were more likely contain hermaphrodites low This consistent prediction key determinant frequency. Our results suggest explain ratio among species.