Floral and reproductive traits frequently influence pollinator behaviour and plant reproductive success and are therefore thought to be under selection. However, for wild plant populations there is little information on the amount of genetic variation for such traits. We estimated broad- and narrow-sense heritability of floral and reproductive traits for two populations of the perennial wildflower Penstemon centranthifolius, using a paternal half-sib crossing design in one case, and clonal propagation of ramets from different genets in the other. In both designs, most traits were significantly heritable, including nectar production, corolla length and width, inflorescence length and total flower production. Flowering date was significantly heritable for the crosses, but not for the clones, while nectar sugar concentration was not significantly heritable in either design. Genetic correlations were in some cases strong, and in some cases differed greatly from the corresponding phenotypic correlations. These results indicate that P. centranthifolius harbours a large reservoir of genetic variance which could support an evolutionary response to phenotypic selection.
Bibliographical noteFunding Information:
We thank Karen Mitchell, Nick Waser, Arlee Montalvo, Steve Morgan, Andy Sanders, Robert Podoisky, Ann Evans, Iva and Joe Lubin, and two anonymous reviewers for help in the field, help measuring traits, valuable advice, and suggestions on the manuscript. Bill Hauser kindly allowed us to remove plants from his property. Len Nunney and David Reznick encouraged us to include study of clones. The USFS provided permission to work on public lands, and lathhouse space was provided by the Department of Biology and the Department of Botany and Plant Sciences at the University of California Riverside. Supported by grants from the California Native Plant Society, the Chapman Fund of the Ameri- can Museum of Natural History, the Hardman Fund for Evolution and Conservation Study, the Newell Fund of the University of California Riverside, the Riverside—San Bernardino Audubon Society, and the Southern California Botanists.
- Genetic correlation
- Penstemon centranthifolius