Cytoplasmic male sterility in Mimulus hybrids has pleiotropic effects on corolla and pistil traits
- 19 January 2011
- journal article
- Published by Springer Science and Business Media LLC in Heredity
- Vol. 106 (5), 886-893
- https://doi.org/10.1038/hdy.2010.133
Abstract
The mechanisms underlying genetic associations have important consequences for evolutionary outcomes, but distinguishing linkage from pleiotropy is often difficult. Here, we use a fine mapping approach to determine the genetic basis of association between cytonuclear male sterility and other floral traits in Mimulus hybrids. Previous work has shown that male sterility in hybrids between Mimulus guttatus and Mimulus nasutus is due to interactions between a mitochondrial gene from M. guttatus and two tightly linked nuclear restorer alleles on Linkage Group 7, and that male sterility is associated with reduced corolla size. In the present study, we generated a set of nearly isogenic lines segregating for the restorer region and male sterility, but with unique flanking introgressions. Male-sterile flowers had significantly smaller corollas, longer styles and greater stigmatic exsertion than fertile flowers. Because these effects were significant regardless of the genotypic composition of introgressions flanking the restorer region, they suggest that these floral differences are a direct byproduct of the genetic incompatibility causing anther abortion. In addition, we found a non-significant but intriguing trend for male-sterile plants to produce more seeds per flower than fertile siblings after supplemental pollination. Such pleiotropic effects may underlie the corolla dimorphism frequently observed in gynodioecious taxa and may affect selection on cytoplasmic male sterility genes when they initially arise.Keywords
This publication has 56 references indexed in Scilit:
- The Nuclear Component of a Cytonuclear Hybrid Incompatibility in Mimulus Maps to a Cluster of Pentatricopeptide Repeat GenesGenetics, 2010
- Linking the Evolution of Gender Variation to Floral DevelopmentAnnals of Botany, 2007
- Relaxed pollinator‐mediated selection weakens floral integration in self‐compatible taxa ofLeavenworthia(Brassicaceae)American Journal of Botany, 2006
- Genetic constraints on floral evolution: a review and evaluation of patternsHeredity, 2006
- MINOR QUANTITATIVE TRAIT LOCI UNDERLIE FLORAL TRAITS ASSOCIATED WITH MATING SYSTEM DIVERGENCE IN MIMULUSEvolution, 2002
- Testing Hypotheses of Functional Relationships: A Comparative Survey of Correlation Patterns Among Floral Traits in Five Insect-Pollinated PlantsAmerican Journal of Botany, 1995
- Reproductive Allocation in Hermaphrodite and Female Plants of Sidalcea oregana ssp. Spicata (Malvaceae) Using Four CurrenciesAmerican Journal of Botany, 1994
- Ecological Consequences and Phenotypic Correlates of Petal Size Variation in Wild Radish, Raphanus sativus (Brassicaceae)American Journal of Botany, 1988
- Gynodioecy in Plantago lanceolata L. IV. Fitness Components of Sex Types in Different Life Cycle StagesEvolution, 1984
- Intra-sexual selection in DrosophilaHeredity, 1948