Skip to main content
ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Invasive Species and Pollinator Health » Research » Publications at this Location » Publication #340939

Research Project: Watershed-scale Assessment of Pest Dynamics and Implications for Area-wide Management of Invasive Insects and Weeds

Location: Invasive Species and Pollinator Health

Title: Germination and seedling growth of water primroses: A cross experiment between two invaded ranges with contrasting climates

Author
item Gillard, Morgane - University Of Rennes, France
item Grewell, Brenda
item Futrell, Caryn
item Deleu, Carole - University Of Rennes, France
item Thiebaut, Gabrielle - University Of Rennes, France

Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/18/2017
Publication Date: 9/26/2017
Citation: Gillard, M., Grewell, B.J., Futrell, C.J., Deleu, C., Thiebaut, G. 2017. Germination and seedling growth of water primroses: A cross experiment between two invaded ranges with contrasting climates. Frontiers in Plant Science. 8:1677. https://doi.org/10.3389/fpls.2017.01677.
DOI: https://doi.org/10.3389/fpls.2017.01677

Interpretive Summary: Aquatic ecosystems are vulnerable to biological invasions, and are also predicted to be strongly impacted by climate change. Understanding the colonization dynamics of aquatic invasive plant species is of high importance for management strategies to preserve native biodiversity, and to maintain water quality for beneficial uses. Many aquatic invasive plants rely on clonal reproduction to spread, but mixed reproductive modes are common. A shift of resource allocation to sexual reproduction is an advantage for populations to regenerate in changing environmental conditions. Thus, under future climate change, these species may favor a sexual reproductive mode. The aim of this study was to test the germination capacity and the seedling growth of two South American Ludwigia species invasive in Europe and in the USA, under contrasted climates. We performed a reciprocal transplant of seeds of Ludwigia hexapetala and L. peploides from two invaded ranges simultaneously into experimental gardens characterized by Oceanic and Mediterranean climates. Study locations were Rennes, France and Davis, California. Our results showed that higher temperatures increased or maintained germination rates and velocity, decreased survivorship of germinants, but increased their production of biomass. The origin of the seeds had low impact on L. hexapetala responses to temperature, but greatly influenced those of L. peploides. The invasiveness of water primroses in ranges with oceanic climates might increase with temperature rise due to increased sexual reproduction. The recruitment from seed banks by these species should be considered by managers to improve the conservation of native aquatic and wetland plant species.

Technical Abstract: Aquatic ecosystems are vulnerable to biological invasions, and are also predicted to be strongly impacted by climate change. Understanding the colonization dynamics of aquatic invasive plant species is of high importance for preservation of native biodiversity. Many aquatic invasive plants rely on clonal reproduction to spread, but mixed reproductive modes are common. A shift of resource allocation to sexual reproduction is an advantage for populations to regenerate in changing environmental conditions. Thus, under future climate change, these species may favor a sexual reproductive mode. The aim of this study was to test the germination capacity and the seedling growth of two Ludwigia species invasive in Europe and in the USA, under contrasted climates. We performed a reciprocal transplant of seeds of Ludwigia hexapetala and L. peploides from two invaded ranges simultaneously into experimental gardens characterized by Oceanic and Mediterranean climates. Our results showed that higher temperatures increased or maintained germination rates and velocity, decreased survivorship of germinants, but increased their production of biomass. The origin of the seeds had low impact on L. hexapetala responses to temperature, but greatly influenced those of L. peploides. The invasiveness of water primroses in ranges with oceanic climates might increase with temperature rise due to increased sexual reproduction. The recruitment from seed banks by these species should be considered by managers to improve the conservation of native aquatic and wetland plant species.