Community composition of arbuscular mycorrhizal fungi associated with native plants growing in a petroleum‐polluted soil of the Amazon region of Ecuador

Abstract

Arbuscular mycorrhizal fungi (AMF) are worldwide distributed plant symbionts. However, their occurrence in hydrocarbon-polluted environments is less investigated, although specific communities may be present with possible interest for remediation strategies. Here, we investigated the AMF community composition associated with the roots of diverse plant species naturally recolonizing a weathered crude oil pond in the Amazon region of Ecuador. Next generation 454 GS-Junior sequencing of an 800 bp LSU rRNA gene PCR amplicon was used. PCR amplicons were affiliated to a maximum-likelihood phylogenetic tree computed from 1.5 kb AMF reference sequences. A high throughput phylogenetic annotation approach, using an evolutionary placement algorithm (EPA) allowed the characterization of sequences to the species level. Fifteen species were detected. Acaulospora species were identified as dominant colonizers, with 73% of relative read abundance, Archaeospora (19.6%) and several genera from the Glomeraceae (Rhizophagus, Glomus macrocarpum-like, Sclerocystis, Dominikia and Kamienskia) were also detected. Although, a diverse community belonging to Glomeraceae was revealed, they represented <10% of the relative abundance in the Pond. Seventy five % of the species could not be identified, suggesting possible new species associated with roots of plants under highly hydrocarbon-polluted conditions.

Phenol and Polyaromatic Hydrocarbons Are Stronger Drivers Than Host Plant Species in Shaping the Arbuscular Mycorrhizal Fungal Component of the Mycorrhizosphere

“…The AMF communities inhabiting the contaminated soil accounted for four to ten species, which half the number at the uncontaminated site. The number of AMF operational taxonomic units (OTUs) reported in other studies conducted at sites contaminated with petroleum hydrocarbons ranged from eight to 30 OTUs [ 13 , 17 , 18 , 32 , 33 , 34 ]; however, in these studies the OTUs were not grouped according to their species affiliation.…”

Analysis of arbuscular mycorrhizal fungi (AMF) community composition associated with alkaline saline sodic soils

“…In contrast to prior studies, which linked Acaulospora with acid soils and low soil EC (Morton 1986; Veresoglou et al, 2013; Vieira et al, 2020; Akaji et al, 2022), our research reveals a broader adaptability. Similarly, Garcés‐Ruiz et al, (2019) detected that Acaulospora thrives not only in alkaline soils with a pH 8 but also in environments with lower pH levels ranging from 5 to 6, showcasing its remarkable versatility. On the other hand, an inhibition of Acaulospora spore germination has been observed in saline environments (Juniper & Abbott 2006).…”

Soil Fungal Diversity of the Aguarongo Andean Forest (Ecuador)

“…Most Ecuadorian studies on soil fungi describe the diversity of arbuscular mycorrhizal fungi (AMF) associated with crops in the Andean part of Loja and Quito [ 47 , 48 ]. There are also studies of the communities of AMF associated with plants growing in contaminated soils such as crude-oil-contaminated sites in the Amazon region of Ecuador [ 20 ]. Using modern molecular methods, it was possible to obtain a detailed account of soil fungal biodiversity of the Aguarongo forest and give the first list of soil fungi of this important reserve of biodiversity in Ecuador.…”

“…Many papers focus on pathogenic fungi for important crops or on the relation between fungi and environments [ 16 , 17 , 18 , 19 ]. Recently, environmental fungal DNA was analyzed for community composition studies of disturbed areas [ 20 , 21 ] or specific substrates such as plants [ 22 , 23 ]. Investigation of mycobiota of natural areas in Ecuador focused on biodiversity, distribution, and ecology of mycorrhizae [ 24 , 25 , 26 ].…”