The purpose of this investigation was to determine the effect of soil microbes on Lythrum spp: purple loosestrife (Lythrum salicaria) and winged loosestrife (Lythrum alatum) from the Midwest region of the USA. Wetlands provide essential ecosystem services such as water purification and flood control. Purple loosestrife, an herbaceous perennial, has spread in wetlands throughout the eastern United States and Canada, becoming a serious threat to the biodiversity of wetlands. It forms dense stands, crowding out native plants, resulting in loss of habitat for native plant and animal species and changes in nutrient flows within the wetland ecosystem. Purple Loosestrife can be observed growing in wet areas that receive runoff containing high levels of nutrients due to inorganic or organic fertilizer. Seeds for purple loosestrife from Sussex County NJ, USA, and the United Kingdom, and winged loosestrife were grown under greenhouse conditions and the soil was inoculated with arbuscular mycorrhiza fungi, wetland soil from Sussex County, NJ, and a topsoil/sand mixture. The wetland soil was from the same location from which the purple loosestrife seeds from Sussex County were collected.
Results/Conclusions
Purple loosestrife plants from Sussex County seeds had the same height and mass under all three conditions, while purple loosestrife plants from United Kingdom seeds and winged loosestrife plants from Midwest USA seeds showed lower growth when the soil was inoculated with wetland soil from Sussex County NJ, USA. There are soil microbes that have a beneficial effect on plants, while others have a detrimental effect. These results show that the relationship between purple loosestrife from Sussex County and the local soil microbes allows the plants to grow in this soil without the potentially detrimental effects that could have impacted the purple loosestrife from the United Kingdom and the winged loosestrife plants.