Mentor/s
Dr. LaTina Steele
Participation Type
Poster
Abstract
Invasive aquatic plants often reduce native biodiversity, but factors contributing to successful invasions are incompletely understood. Invasive plants may produce more chemical deterrents like phenolic compounds than native plants, allowing the invasive species to avoid consumption by native grazers. This study investigated the distribution of phenolics in invasive Myriophyllum spicatum (milfoil) and native Ceratophyllum demersum (coontail) and the effects of phenolics on amphipod grazing. Phenolic levels in fragments from the apical and middle portions of M. spicatum and C. demersum were measured. Those same plant tissues were offered to amphipods in two no-choice feeding experiments. One experiment used live plant fragments, while the other experiment used an artificial diet prepared from freeze-dried, ground plant tissues. Milfoil apex tissue produced more phenolics than any other tissue, with four times more phenolics in milfoil apex tissue than in either apex or middle tissue from coontail. There were no significant differences in amphipod consumption of apex and middle tissues from milfoil or coontail in either feeding experiment. Although M. spicatum contained more phenolics than coontail, phenolics were not an effective defense against amphipod feeding. Therefore, it is unlikely that reduced consumption by amphipods contributes to successful M. spicatum invasions.
College and Major available
Biology, Philosophy, Theology, Rel. Studies
Location
Digital Commons
Start Day/Time
4-24-2020 2:00 PM
End Day/Time
4-24-2020 4:00 PM
Prize Categories
Most Scholarly Impact or Potential, Best Visuals, Most Creative
Patterns of Chemical Defense Production and Amphipod Grazing in Invasive Myriophyllum spicatum and Native Ceratophyllum demersum
Digital Commons
Invasive aquatic plants often reduce native biodiversity, but factors contributing to successful invasions are incompletely understood. Invasive plants may produce more chemical deterrents like phenolic compounds than native plants, allowing the invasive species to avoid consumption by native grazers. This study investigated the distribution of phenolics in invasive Myriophyllum spicatum (milfoil) and native Ceratophyllum demersum (coontail) and the effects of phenolics on amphipod grazing. Phenolic levels in fragments from the apical and middle portions of M. spicatum and C. demersum were measured. Those same plant tissues were offered to amphipods in two no-choice feeding experiments. One experiment used live plant fragments, while the other experiment used an artificial diet prepared from freeze-dried, ground plant tissues. Milfoil apex tissue produced more phenolics than any other tissue, with four times more phenolics in milfoil apex tissue than in either apex or middle tissue from coontail. There were no significant differences in amphipod consumption of apex and middle tissues from milfoil or coontail in either feeding experiment. Although M. spicatum contained more phenolics than coontail, phenolics were not an effective defense against amphipod feeding. Therefore, it is unlikely that reduced consumption by amphipods contributes to successful M. spicatum invasions.
Students' Information
Cassie Simonides, Double major in Biology and Philosophy, 2020.
Honorable Mention, Dean's Prize: College of Arts and Sciences.