Soil microbiota can boost growth of invasive plant species

Soil microbes can have a great impact on the spread of harmful invasive species as they can either hinder or facilitate the plant's growth. Researchers studied the role of soil microbiota in the success of garden lupine, which is an invasive species in the Finnish nature. Lupinus polyphyllus, commonly known as the garden lupine, is a perennial herb native to North America. It was brought to Europe as an ornamental plant, but it escaped the gardens and is now considered an invasive species in many countries, including Finland. What makes the garden lupine interesting and a successful invading species are the root nodule bacteria which convert atmospheric nitrogen for the plant's use. Nitrogen is needed for growth and in producing phytochemical compounds against herbivores. Soil microbiota can also affect the smell of the plant. The researchers planted garden lupines originating from North American and Finnish populations in nutrient-poor soil containing soil microbes from local lupine populations or in soil where the amount of microbes had been reduced.