2012 S3: Danielle Grimm

Using Artificial Breeding of Eurasian and Northern Watermilfoils to Study the Evolutionary Ecology of Herbicide Resistance

Eurasian watermilfoil is an invasive species that hybridizes with a benign native species. Both Eurasian watermilfoil and hybrids are treated with herbicides the same way. However, hybrids grow more invasively and can exhibit lower response to herbicides. A deeper understanding of the genetic bases of these traits can be achieved with artificial breeding studies. However, surprisingly little is known about the factors influencing flowering, seed maturity, seed viability, and seedling survival. This S3 project developed methods for laboratory breeding of watermilfoils. The factors promoting flowering remain unknown, and it is most efficient to perform crosses using flowering material collected from the field. However, hand pollination of flowering plants leads to reliable fruit production. Furthermore, seeds produced from artificial crosses are viable and have high germination rates under a range of laboratory conditions. Finally, germinated seeds have been successfully grown to seedlings. These methods will prove valuable for evolutionary genetic studies of invasiveness in watermilfoils.

Faculty Mentor: Ryan Thum, Annis Water Resources Institute

Danielle Grimm