Arbuscular mycorrhizal fungal diversity associated with Eleocharis obtusa and Panicum capillare growing in an extreme petroleum hydrocarbon-polluted sedimentation basin.

Arbuscular mycorrhizal fungi (AMF) have been extensively studied in natural and agricultural ecosystems, but little is known about their diversity and community structure in highly petroleum-polluted soils. In this study, we described an unexpected diversity of AMF in a sedimentation basin of a former petrochemical plant, in which petroleum hydrocarbon (PH) wastes were dumped for many decades. We used high-throughput PCR, cloning and sequencing of 18S rDNA to assess the molecular diversity of AMF associated with Eleocharis obtusa and Panicum capillare spontaneously inhabiting extremely PH-contaminated sediments. The analyses of rhizosphere and root samples over two years showed a remarkable AMF richness comparable with that found in temperate natural ecosystems. Twenty-one taxa, encompassing the major families within Glomeromycota, were detected. The most abundant OTUs belong to genera Claroideoglomus, Diversispora, Rhizophagus and Paraglomus. Both plants had very similar overall community structures and OTU abundances; however, AMF community structure differed when comparing the overall OTU distribution across the two years of sampling. This could be likely explained by variations in precipitations between 2011 and 2012. Our study provides the first view of AMF molecular diversity in soils extremely polluted by PH, and demonstrated the ability of AMF to colonize and establish in harsh environments.

de la Providencia IE ，Stefani FO ，Labridy M ，St-Arnaud M ，Hijri M ... -  《-》

Bacteria associated with arbuscular mycorrhizal fungi within roots of plants growing in a soil highly contaminated with aliphatic and aromatic petroleum hydrocarbons.

Arbuscular mycorrhizal fungi (AMF) belong to phylum Glomeromycota, an early divergent fungal lineage forming symbiosis with plant roots. Many reports have documented that bacteria are intimately associated with AMF mycelia in the soil. However, the role of these bacteria remains unclear and their diversity within intraradical AMF structures has yet to be explored. We aim to assess the bacterial communities associated within intraradical propagules (vesicles and intraradical spores) harvested from roots of plant growing in the sediments of an extremely petroleum hydrocarbon-polluted basin. Solidago rugosa roots were sampled, surface-sterilized, and microdissected. Eleven propagules were randomly collected and individually subjected to whole-genome amplification, followed by PCRs, cloning, and sequencing targeting fungal and bacterial rDNA. Ribotyping of the 11 propagules showed that at least five different AMF OTUs could be present in S. rugosa roots, while 16S rRNA ribotyping of six of the 11 different propagules showed a surprisingly high bacterial richness associated with the AMF within plant roots. Most dominant bacterial OTUs belonged to Sphingomonas sp., Pseudomonas sp., Massilia sp., and Methylobacterium sp. This study provides the first evidence of the bacterial diversity associated with AMF propagules within the roots of plants growing in extremely petroleum hydrocarbon-polluted conditions.

Iffis B ，St-Arnaud M ，Hijri M 《-》

Arbuscular Mycorrhizal Fungal Communities of Native Plant Species under High Petroleum Hydrocarbon Contamination Highlights Rhizophagus as a Key Tolerant Genus.

Lee SJ ，Kong M ，St-Arnaud M ，Hijri M ... -  《Microorganisms》

Molecular biodiversity of arbuscular mycorrhizal fungi in trace metal-polluted soils.

Hassan Sel D ，Boon E ，St-Arnaud M ，Hijri M ... -  《-》

Diversity of Arbuscular Mycorrhizal Fungi Associated with a Sb Accumulator Plant, Ramie (Boehmeria nivea), in an Active Sb Mining.

Wei Y ，Chen Z ，Wu F ，Li J ，ShangGuan Y ，Li F ，Zeng QR ，Hou H ... -  《-》