Date of Award


Degree Type

Masters Thesis

Degree Name

Master of Science (MS)


Biological, Environmental, and Earth Sciences

Committee Chair

Dr. Jake Schaefer

Committee Chair School

Biological, Environmental, and Earth Sciences

Committee Member 2

Dr. Michael Davis

Committee Member 2 School

Biological, Environmental, and Earth Sciences

Committee Member 3

Dr. Bradley Sartain

Committee Member 3 School

Biological, Environmental, and Earth Sciences


Flowering rush is an invasive aquatic plant in North America that causes deleterious effects to native ecosystems. There are two cytotypes, a triploid and diploid, and multiple genotypes contained within the diploid cytotype currently established in the U.S. Despite its presence in river drainages connected to estuarine areas, documentation on the salinity tolerance of flowering rush is scarce. Currently, information is limited to anecdotal reports suggesting intolerance to saline conditions. A better understanding of the osmotic tolerance of this species is essential to providing insight into its’ invasive range and better inform management efforts. These studies investigated vegetative propagule germination and growth of four genotypes of flowering rush when exposed to a range of salinities (0-35 ppt). Germination and growth were assessed through benchtop and mesocosm experiments. Germination varied among cytotypes with triploids outperforming diploids at higher salinities. Diploid genotypes showed a significant decrease in germination past 5ppt, while triploid germination were equivalent to the control up to 15ppt. Propagules remained viable following salinity exposure indicating that vegetative reproductive structures are capable of persisting until more favorable conditions are met. In the growth study, ANOVA indicated no genotype effect, but a significant salinity treatment effect. When averaged across genotype, mean relative daily growth rate was significantly lower for all treatments when compared to the control and no differences were detected among treatments at treatments greater than 10ppt. This study corroborates previous classification of this species as a glycophyte or intolerant to saline conditions.



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Weed Science Commons