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Biology subjects

Mondy, S.

Publications and source records attributed to Mondy, S..

2 recordsLinked to original sources

Accurate MAG reconstruction from complex soil microbiome through combined short- and HiFi long-reads metagenomics

BackgroundAdvances in high-fidelity long-read (HiFi-LR) sequencing technologies have opened new opportunities to explore the microbial genomic diversity of complex environments, such as soils. While short-read (SR) sequencing has enabled broad insights at the gene level, the limited read length constrains the reconstruction of complete genomes. HiFi-LRs, in contrast, improve assembly continuity and completeness, supporting higher-resolution taxonomic and functional annotation. However, the cost and relatively low throughput of HiFi-LR sequencing can limit genome recovery--particularly at the binning stage, where coverage depth is critical. In this study, we assess the benefit of combining HiFi-LR and SR sequencing for genome-resolved characterization of a soil microbiome. ResultsWe generated metagenomic data for a tunnel-cultivated soil sample using high coverage Illumina SRs as well as a combination of two HiFi-LR sequencing platforms (PacBio Sequel II and PacBio Revio). We found that assemblies generated from pooled HiFi-LR data alone exhibited higher completeness compared to those from ultra-deep SR data. Incorporating SR-derived coverage information for the binning of HiFi-LR contigs further increased both the number and quality of recovered metagenome-assembled genomes (MAGs), with a 24% increase in MAG recovery (313 vs. 252) and lower contamination levels (116 vs. 132 contaminated bins; mean 7.09 vs. 8.07), compared to using HiFi-LR data alone. This approach enabled the recovery of 61 additional MAGs, including 67% of low-abundance and taxonomically diverse lineages such as Archaea, representing 36 novel lineages. ConclusionOur results demonstrate that integrating HiFi-LR and SR sequencing markedly enhances genome recovery and binning accuracy in a highly diverse environment such as soil. The hybrid approach employed leverages the strengths of both technologies, leading to more contiguous assemblies and enabling the recovery of a broader range of genomes, including low-abundance and taxonomically diverse taxa. While factors such as sequencing depth, cost, and DNA quality remain important considerations, our study provides practical guidance for designing future soil metagenomics projects and underscores the value of adopting long-read technologies for more comprehensive characterization of complex microbial communities.

genomics↗

Neighbourhood effect of weeds on wheat root endospheric mycobiota

O_LIMicroorganisms associated with plants provide essential functions to their hosts, and therefore affect ecosystem productivity. Agricultural intensification has modified microbial diversity in the soil reservoir and may affect plant microbial recruitment. Weeds develop spontaneously in crop fields, and could influence microorganisms associated with crop plants through a neighbourhood effect. We explore the effect of weed species on crop plant microbiota as potentially auxiliary plants that affect agricultural productivity. C_LIO_LIWe combined field and controlled laboratory studies to analyse the neighbourhood effect of weeds on wheat root endospheric mycobiota and growth. First, we analysed the effect of weed species diversity and identity recorded in the neighbourhood of individual wheat plants on soil and wheat root mycobiota in the field. Second, we used a plant-matrix design in laboratory conditions to test the effect of weed identity (9 weed treatments) and their ability to transmit root mycobiota to wheat roots, and the resulting impact on wheat growth. C_LIO_LIIn contrast to soil mycobiota, we demonstrated that wheat root endospheric mycobiota was influenced by the diversity and identity of weeds developing in their 1 m2 neighbourhood. Wheat root endospheric microbiota strongly differs in terms of richness and composition depending on the neighbouring weed plant species. Weed species transmitted from 13% to 74% of their root microbiota to wheat roots depending on weed identity in controlled conditions. C_LIO_LISynthesis. Weed neighbours modified wheat plant performance, possibly as a result of competitive interactions and changes in microbiota. Our findings suggest that crop root mycobiota was variable and was modulated by their weed neighbourhood. Synergistic effects between mycobiota of crops and weeds could therefore contribute to soil biodiversity and sustainable agriculture. C_LI

ecology↗