Variation in Resistance of Experienced and Naive Seedlings of Jewelweed (Impatiens Capensis) to Invasive Garlic Mustard (Alliaria Petiolata) (Brief Note) (Report‪)‬

ABSTRACT. The invasive species garlic mustard, Alliaria petiolata, has negative impacts on understory forest species in the Midwest. Plants that coexist with A. petiolata in the field may show resistance to its negative effects as a result of natural selection. In a growth room experiment, we investigated if naive and experienced seedlings of Impatiens capensis vary in their response to the presence of A. petiolata. Impatiens capensis individuals from areas without A. petiolata (i.e., naive plants) and from nearby areas with A. petiolata (i.e., experienced plants) were collected from the field and were then grown with A. petiolata in pots for 16 weeks. We measured height, stem diameter, reproduction and biomass of I. capensis and biomass of A. petiolata. There was a significant (P 0.05) negative correlation between biomass and height of naive I. capensis and biomass of A. petiolata, while there was no significant correlation between these variables for experienced I. capensis. Our results indicate the potential for the evolution of resistance to the presence of A. petiolata in I. capensis and point toward the need for further studies. INTRODUCTION