Trombley Josh, Celenza John L, Frey Serita D, Anthony Mark A
Center for Soil Biogeochemistry and Microbial Ecology, Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire, USA.
Department of Biology, Boston University, Boston, Massachusetts, USA.
Plant Cell Environ. 2025 Jul;48(7):4928-4937. doi: 10.1111/pce.15508. Epub 2025 Mar 25.
Invasive plant growth is affected by interactions with arbuscular mycorrhizal fungi (AMF). AMF are mutualists of most land plants but suppress the growth of many plants within the Brassicaceae, a large plant family including many invasive species. Alliaria petiolata (garlic mustard) is a nonnative, nonmycorrhizal Brassicaceae distributed throughout North America in forest understories where native species rely on AMF. If AMF suppress growth of garlic mustard, it may be possible to inoculate AMF to manage invasions. Here, we show that in contrast to expectation, garlic mustard growth nearly doubled in response to AMF inoculation under both laboratory and field conditions. This effect was negatively linked to investments in glucosinolates, a class of defensive compounds. In contrast to typical symbiosis, AMF did not produce arbuscules where nutrient exchange occurs in roots, but AMF inoculation increased plant and soil nitrogen availability. Our findings reveal an adjacent pathway by which AMF promote invasive plant growth without classic symbiotic exchanges. Prior assumptions that garlic mustard suppresses AMF are inadequate to explain invasion success since it benefits from interactions with AMF. This study is the first to demonstrate extensive growth promotion following AMF inoculation in mustard plants, with important implications for invasion biology and agriculture.
入侵植物的生长会受到与丛枝菌根真菌（AMF）相互作用的影响。AMF是大多数陆地植物的共生菌，但会抑制十字花科许多植物的生长，十字花科是一个包含许多入侵物种的大型植物科。北美独行菜（蒜芥）是一种非本土的、非菌根的十字花科植物，分布于北美各地的森林下层，而当地物种依赖AMF。如果AMF抑制蒜芥的生长，那么接种AMF可能有助于控制其入侵。在此，我们发现，与预期相反，在实验室和田间条件下，接种AMF后蒜芥的生长几乎增加了一倍。这种效应与对一类防御性化合物——硫代葡萄糖苷的投入呈负相关。与典型的共生关系不同，AMF在根中发生养分交换的部位并未形成丛枝，但接种AMF增加了植物和土壤中的氮含量。我们的研究结果揭示了一条相邻的途径，通过这条途径，AMF在没有经典共生交换的情况下促进入侵植物的生长。先前认为蒜芥会抑制AMF的假设不足以解释其入侵成功的原因，因为它从与AMF的相互作用中受益。这项研究首次证明了接种AMF后芥菜植物的广泛生长促进作用，对入侵生物学和农业具有重要意义。
