How Does Heat-Stress Intensity Affect the Stability of Microbial Activity and Diversity of Soil Microbial Communities in Outfields and Homefields’ Cultivation Practices in the Senegalese Groundnut Basin?  

作　　者：Paul Ndiaga Ciss Laure Tall Saidou Nourou Sall Mariama Dalanda Diallo Paula Fernandes Tidiane Dieye Medoune Mbengue Espoir Gaglo Komi Assigbetse Paul Ndiaga Ciss;Laure Tall;Saidou Nourou Sall;Mariama Dalanda Diallo;Paula Fernandes;Tidiane Dieye;Medoune Mbengue;Espoir Gaglo;Komi Assigbetse(LABAAM, UFR S2ATA, Université Gaston Berger, Saint Louis, Sénégal;ISRA (Institut Sénégalais de Recherche Agricole), LNRPV, Dakar, Sénégal;IPAR (Initiative Prospective Agricole et Rurale), Dakar, Sénégal;LMI IESOL, Centre ISRA-IRD-UCAD, Dakar, Sénégal;CIRAD, UPR Hortsys, Centre ISRA-IRD-UCAD, Dakar, Sénégal;Eco & Sols, Université de Montpellier, IRD, CIRAD, INRAE, Institut Agro, Montpellier, France;Hortsys, CIRAD, Univ Montpellier, Montpellier, France)

机构地区：[1]LABAAM, UFR S2ATA, Université Gaston Berger, Saint Louis, Sénégal [2]ISRA (Institut Sénégalais de Recherche Agricole), LNRPV, Dakar, Sénégal [3]IPAR (Initiative Prospective Agricole et Rurale), Dakar, Sénégal [4]LMI IESOL, Centre ISRA-IRD-UCAD, Dakar, Sénégal [5]CIRAD, UPR Hortsys, Centre ISRA-IRD-UCAD, Dakar, Sénégal [6]Eco & Sols, Université de Montpellier, IRD, CIRAD, INRAE, Institut Agro, Montpellier, France [7]Hortsys, CIRAD, Univ Montpellier, Montpellier, France

出　　处：《Open Journal of Soil Science》2023年第2期97-123,共27页土壤科学期刊（英文）

摘　　要：Agroecosystems in the Senegalese groundnut basin experience long periods of high temperatures and drought, which disrupt the stability of soil microbial communities. This study evaluated how that stability is affected by homefields and outfields’ agricultural practices and the duration of heat stress. Specifically, we collected soils from organically farmed fields that receive continual high inputs of manure (homefields), and from fields that are rarely manured (outfields). Soil samples were submitted to artificial heat stress at 60°C for 3, 14, and 28 days, followed by 28 days of recovery at 28°C. We examined the functional stability of microbial communities by quantifying C mineralization, and characterized the stability of the communities’ taxonomic compositions via high-throughput DNA sequencing. We found that the microbial communities have a low resistance to heat stress in soils from both types of fields. However, the manuring practice does affect how the functional stability of microbial communities responds to different durations of heat stress. Although functional stability was not recovered fully in either soil, microbial community resilience seemed to be greater in homefield soils. Differences in manuring practices also affected the structural taxonomic stability of microbial communities: relative abundances of Bacilli, Chloroflexia, Actinobacteria and Sordariomycetes increased in the homefield stressed-soils, but decreased significantly in outfield soils. In contrast, relative abundances of α-Proteobacteria, γ-Proteobacteria and Eurotiomycetes increased significantly in outfield stressed-soils, while decreasing significantly in the homefield soils. Relative abundances of Bacilli changed little in outfield soils, indicating that this taxon is resistant to heat stress. In summary, the microbial communities’ capacities to resist heat stress and recover from it depend upon the organic richness of the soil (i.e., manuring practice) and the adaptation of soil microbes to environmental conditions.Agroecosystems in the Senegalese groundnut basin experience long periods of high temperatures and drought, which disrupt the stability of soil microbial communities. This study evaluated how that stability is affected by homefields and outfields’ agricultural practices and the duration of heat stress. Specifically, we collected soils from organically farmed fields that receive continual high inputs of manure (homefields), and from fields that are rarely manured (outfields). Soil samples were submitted to artificial heat stress at 60°C for 3, 14, and 28 days, followed by 28 days of recovery at 28°C. We examined the functional stability of microbial communities by quantifying C mineralization, and characterized the stability of the communities’ taxonomic compositions via high-throughput DNA sequencing. We found that the microbial communities have a low resistance to heat stress in soils from both types of fields. However, the manuring practice does affect how the functional stability of microbial communities responds to different durations of heat stress. Although functional stability was not recovered fully in either soil, microbial community resilience seemed to be greater in homefield soils. Differences in manuring practices also affected the structural taxonomic stability of microbial communities: relative abundances of Bacilli, Chloroflexia, Actinobacteria and Sordariomycetes increased in the homefield stressed-soils, but decreased significantly in outfield soils. In contrast, relative abundances of α-Proteobacteria, γ-Proteobacteria and Eurotiomycetes increased significantly in outfield stressed-soils, while decreasing significantly in the homefield soils. Relative abundances of Bacilli changed little in outfield soils, indicating that this taxon is resistant to heat stress. In summary, the microbial communities’ capacities to resist heat stress and recover from it depend upon the organic richness of the soil (i.e., manuring practice) and the adaptation of soil microbes to environmental conditions.

关 键 词：Groundnut Basin Senegal Agricultural Practice Heat Stress Microbial Stability Microbial Diversity 

分 类 号：S15[农业科学—土壤学]