The performance of native and invasive Myriophyllum species under different abiotic conditions
Aquatic plant species are dependent on a number of abiotic factors that can influence their growth, and persistence in given habitats. Temperature, light and dissolved inorganic carbons are three factors that have been shown to significantly influence the fitness of aquatic plant species. In this study, growth parameters of two Myriophyllum species, Myriophyllum spicatum (native to the EPPO region and invasive in North America) and Myriophyllum heterophyllum (an invasive alien in the EPPO region) were evaluated under varying abiotic conditions in a three factorial experimental design (light x temperature x CO2). The two species differed significantly in their relative growth rates (RGR) and their growth response to different growth conditions. Both had a maximum RGR at 21oC, though it was significantly higher in M. spicatum. The RGR of M. heterophyllum was significantly increased with CO2. Light was shown to significantly increase RGR for both species. Both species were able to utilize HCO3− (bicarbonate) which was higher in plants acclimated to low levels of CO2. However, M. spicatum showed an overall greater efficancy for HCO3− utilisation.
Hussner A, Jahns P (2015) European native Myriophyllum spicatum showed a higher HCO3− use capacity than alien invasive Myriophyllum heterophyllum. Hydrobiologia 746, 171-182.