Author
Espeland, Erin | |
HAMMOND, DARCY - Mississippi State University |
Submitted to: Ecological Applications
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/1/2013 Publication Date: 10/1/2013 Publication URL: http://handle.nal.usda.gov/10113/58312 Citation: Espeland, E.K., Hammond, D.H. 2013. Maternal effects on growth and competitive ability in a commonly used restoration species. Ecological Applications. 14(3):231-242. Interpretive Summary: Plants growing in poor environments often produce small seeds that do not germinate well. However, in some cases, plants provision their seeds to perform best in the environment that matches that of the maternal plants. In species where this provisioning occurs, manipulating maternal effects in production gardens may improve the performance of seeds planted in large-scale restoration. We tested seeds from plants of a commonly-used restoration species, Sandberg’s bluegrass (Poa secunda) grown in three different production garden environments. We measured performance at five life history stages: germination, emergence, growth, competitive tolerance, and competitive ability. We found that the production garden affected seed size in some maternal families more than others. Seed size was correlated with root morphology, with larger seeds producing more root volume at the end of the growing season. Larger seeds conferred better germination and higher competitive ability only in some environments. There were also effects of production garden that were uncorrelated with seed size: early plant size, final plant size, and competitive tolerance. Production garden influenced plant performance in positive ways beyond the simple effect of larger seeds, and by understanding the influence of maternal effects under field conditions, we may be able to choose production environments that maximize the performance of restoration seeds in this species. Technical Abstract: Adaptive maternal effects are when plants provision their seeds to perform best in the environment that matches that of the maternal plants. Manipulating maternal effects in production gardens may improve the performance of seeds planted in large-scale restoration. In ex-situ experiments, we tested seeds of Poa secunda produced by the same maternal families grown in three different production garden environments. We measured progeny performance at five life history stages: germination, emergence, growth, competitive tolerance, and competitive ability. We found that the production garden affected seed size in some maternal families more than others. Seed size was correlated with root morphology, with larger seeds producing more root volume at the end of the growing season. Larger seeds conferred better germination and higher competitive ability only in some progeny growth environments. There were also effects of production garden that were uncorrelated with seed size: early plant size, final plant size, and competitive tolerance. Adaptive maternal effects were found for germination in one production environment and for early plant size in another production environment. Production garden influenced plant performance in positive ways beyond the simple effect of larger seeds, and by understanding the influence of maternal effects under field conditions, we may be able to choose production environments that maximize the performance of restoration seeds in this species. |