Effects of invasive plants interacting with native plants on colonization of arbuscular mycorrhizal fungi.
The successful invasion of exotic plants is closely related to the mycorrhizal symbiosis. The colonization percentage of arbuscular mycorrhizal fungi (AMF) is an important indicator reflecting the colonization status of AMF on plants. There are many factors affecting the colonization percentage, but the impact of invasive plants interacting with native plants on the AMF colonization percentage is still unclear. In the present study, the invasive plants Flaveria bidentis, Ambrosia artemisiifolia and Bidens pilosa and native plants Setaria viridis, Melilotus officinalis and Chenopodium album were used as research objects to observe the root arbuscule, vesicule, hypha and total colonization percentage of invasive plants and native plants under different treatments. The monoculture treatment of invasive plants, the monoculture treatment of native plants, the mixed cultivation treatment of alternative invasive plant and alternative native plant and the mixed cultivation treatment of alternative invasive plant and multiple native plants are designed. The effects of alternative cultivation of native plant species on the AMF colonization percentage of invasive plants and native plant roots, and the effects of three invasive Compositae plants on the AMF colonization percentage of native plants are compared. The results showed that as compared with the monoculture treatment of invasive plants, the hypha and the total colonization percentage of Ambrosia artemisiifolia increased in mixed cultivation of Ambrosia artemisiifolia and Chenopodium album and in that of Ambrosia artemisiifolia and three native plants. There was no significant difference in total root infestation percentage of invasive plants in other cultivation treatments. As compared with the monoculture treatment of Setaria viridis and Melilotus officinalis, the AMF hyphae and total invasion rate of native plant Setaria viridis and Melilotus officinalis significantly reduced in the mixed cultivation treatment of alternative invasive plant and all experimental native plants. The hyphae and total colonization percentage of native plants were significantly inhibited with the increase of diversity of native plant species, but those of invasive plants were not influenced.