Collaborative Research: Determinants of the spread of beneficial fungi and their relation to invasion by non-native pine trees

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

Biological invasions create enormous environmental and social problems, impose a huge economic cost, and threaten biodiversity. Studying invasions aids environmental management and increases understanding of natural system dynamics. Fungi are one of the least understood groups of invasive species, despite being an essential component of biodiversity and having tremendous ecological significance. Fungal control of plant invasion will be studied on an island in Argentina where a century ago more than 130 exotic trees species were planted, including many that are highly invasive elsewhere. Surprisingly few of these species have become widespread on this island. Previous research shows that lack of mycorrhizal fungi (root symbionts that are key to plant survival) limits spread of invasive plant species in the area. These fungi form mutualisms with only a few plant species, and the plants and the fungi are dispersed independently, so the plants may not 'find' mutualistic fungi. This project will elucidate how fungal dispersal aids spread of invasive trees. Introduced species that eat fungi, such as European boar and deer, may disperse fungi in their feces, generating a feedback between the exotics and increasing the impacts of the invading trees. Fungi can also spread belowground and thus promote establishment of the introduced trees. This project will show how mammals, wind, and belowground growth influence fungal spread and subsequent invasion by exotic conifers, one of the most aggressive groups of invasive plants. The 21st century may bring a great loss of biodiversity. Invasive species are a leading factor, also producing huge economic losses. To manage biological invasions effectively to minimize these environmental and economic costs, we must understand the factors regulating invasions: this is the goal of this study. In addition, this will contribute to our understanding of fungal biology and its influence on plant ecology, which will advance the ecological sciences.