Invasion of a xeric forest by an exotic tree species in Argentina: Impacts on the diversity of arbuscular mycorrhizal fungi and pre-existing mutualistic relationships

Abstract

This study aimed to analyse the effects of invasion by the exotic Ligustrum lucidum on mycorrhizal associations in forests of Celtis tala, and to determine the role that these fungi play in the invasion process. We analyzed colonization and response to mycorrhization of both plant species under greenhouse conditions after inoculation with soil obtained from patches of non-invaded native forests and invaded forests. The spores present in pots at the end of the experiment were counted and identified. Colonization of L. lucidum was greater in plants inoculated with invaded forest soil, whereas colonization of C. tala was greater in plants inoculated with non-invaded native forest soil. Principal component analysis of fungal species abundance showed differences in AMF composition according to host plant and forest type. The results show that L. lucidum establishes symbiosis with native AMF, which triggers changes in community structure. These changes favored the mycorrhization of L. lucidum and interfered with the mycorrhization of C. tala. AMF may have either a direct or indirect role in the invasion process, not only benefiting the invasive species but also preventing the regeneration of native plants.

On the Occurrence of Arbuscular Mycorrhizal Fungi in a Bryophyte Community of Punta Lara Natural Reserve, Buenos Aires, Argentina

“…To guarantee AMF conservation in ecosystems where they naturally occur, studies in reserves and undisturbed areas should be deepened to know the AMF baseline diversity. Long-term strategies are also urgently needed to maintain their diversity [29]. The Punta Lara Natural Reserve (PLNR) is located on the coast of the Río de la Plata, eastern Pampas of the Buenos Aires province, a region of global importance for its agricultural production.…”