Responses of Low-Cost Input Combinations on the Microbial Structure of the Maize Rhizosphere for Greenhouse Gas Mitigation and Plant Biomass Production

The microbial composition of the rhizosphere and greenhouse gas (GHG) emissions under the most common input combinations in maize (Zea mays L.) cultivated in Brazil have not been characterized yet. In this study, we evaluated the influence of maize stover coverage (S), urea-topdressing fertilization (F), and the microbial inoculant Azospirillum brasilense (I) on soil GHG emissions and rhizosphere microbial communities during maize development. We conducted a greenhouse experiment and measured methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) fluxes from soil cultivated with maize plants under factorial combinations of the inputs and a control treatment (F, I, S, FI, FS, IS, FIS, and control). Plant biomass was evaluated, and rhizosphere soil samples were collected at V5 and V15 stages and DNA was extracted. The abundance of functional genes (mcrA, pmoA, nifH, and nosZ) was determined by quantitative PCR (qPCR) and the structure of the microbial community was assessed through 16S rRNA amplicon sequencing. Our results corroborate with previous studies which used fewer input combinations and revealed different responses for the following three inputs: F increased N2O emissions around 1 week after application; I tended to reduce CH4 and CO2 emissions, acting as a plant growth stimulator through phytohormones; S showed an increment for CO2 emissions by increasing carbon-use efficiency. IS and FIS treatments presented significant gains in biomass that could be related to Actinobacteria (19.0%) and Bacilli (10.0%) in IS, and Bacilli (9.7%) in FIS, which are the microbial taxa commonly associated with lignocellulose degradation. Comparing all factors, the IS (inoculant + maize stover) treatment was considered the best option for plant biomass production and GHG mitigation since FIS provides small gains toward the management effort of F application.

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Does root glutamine synthetase control plant biomass production in Lotus japonicus L.?

Planta ◽

10.1007/s004250050753 ◽

1999 ◽

Vol 209 (4) ◽

pp. 495-502 ◽

Cited By ~ 43

Author(s):

Anis Limami ◽

Belinda Phillipson ◽

Rafiqa Ameziane ◽

Nicolas Pernollet ◽

Qunji Jiang ◽

...

Keyword(s):

Glutamine Synthetase ◽

Biomass Production ◽

Plant Biomass ◽

Control Plant ◽

Lotus Japonicus ◽

Plant Biomass Production

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Effects of Biochar Application on Soil Properties, Plant Biomass Production, and Soil Greenhouse Gas Emissions: A Mini-Review

Agricultural Sciences ◽

10.4236/as.2021.123014 ◽

2021 ◽

Vol 12 (03) ◽

pp. 213-236

Author(s):

Dafeng Hui

Keyword(s):

Soil Properties ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Biomass Production ◽

Plant Biomass ◽

Gas Emissions ◽

Plant Biomass Production

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Mangrove diversity enhances plant biomass production and carbon storage in Hainan island, China

Functional Ecology ◽

10.1111/1365-2435.13753 ◽

2021 ◽

Vol 35 (3) ◽

pp. 774-786

Author(s):

Jiankun Bai ◽

Yuchen Meng ◽

Ruikun Gou ◽

Jiacheng Lyu ◽

Zheng Dai ◽

...

Keyword(s):

Carbon Storage ◽

Biomass Production ◽

Plant Biomass ◽

Hainan Island ◽

Plant Biomass Production

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Can repeated soil amendment with biogas digestates increase soil suppressiveness toward non-specific soil-borne pathogens in agricultural lands?

Renewable Agriculture and Food Systems ◽

10.1017/s1742170520000393 ◽

2020 ◽

pp. 1-12

Author(s):

L. M. Manici ◽

F. Caputo ◽

G. A. Cappelli ◽

E. Ceotto

Keyword(s):

Plant Growth ◽

Biomass Production ◽

Soil Amendment ◽

Plant Biomass ◽

Amended Soils ◽

Soil Suppressiveness ◽

Soil Microbial ◽

Soil Borne Pathogens ◽

The Impact ◽

Plant Biomass Production

Abstract Soil suppressiveness which is the natural ability of soil to support optimal plant growth and health is the resultant of multiple soil microbial components; which implies many difficulties when estimating this soil condition. Microbial benefits for plant health from repeated digestate applications were assessed in three experimental sites surrounding anaerobic biogas plants in an intensively cultivated area of northern Italy. A 2-yr trial was performed in 2017 and 2018 by performing an in-pot plant growth assay, using soil samples taken from two fields for each experimental site, of which one had been repeatedly amended with anaerobic biogas digestate and the other had not. These fields were similar in management and crop sequences (maize was the recurrent crop) for the last 10 yr. Plant growth response in the bioassay was expressed as plant biomass production, root colonization frequency by soil-borne fungi were estimated to evaluate the impact of soil-borne pathogens on plant growth, abundance of Pseudomonas and actinomycetes populations in rhizosphere were estimated as beneficial soil microbial indicators. Repeated soil amendment with digestate increased significantly soil capacity to support plant biomass production as compared to unamended control in both the years. Findings supported evidence that this increase was principally attributable to a higher natural ability of digestate-amended soils to reduce root infection by saprophytic soil-borne pathogens whose inoculum was increased by the recurrent maize cultivation. Pseudomonas and actinomycetes were always more abundant in digestate-amended soils suggesting that both these large bacterial groups were involved in the increase of their natural capacity to control soil-borne pathogens (soil suppressiveness).

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Application of Hydrochar, Digestate, and Synthetic Fertilizer to a Miscanthus x giganteus Crop: Implications for Biomass and Greenhouse Gas Emissions

Applied Sciences ◽

10.3390/app10248953 ◽

2020 ◽

Vol 10 (24) ◽

pp. 8953

Author(s):

Toby Adjuik ◽

Abbey M. Rodjom ◽

Kimberley E. Miller ◽

M. Toufiq M. Reza ◽

Sarah C. Davis

Keyword(s):

Greenhouse Gas ◽

Nutrient Management ◽

Agricultural Land ◽

Biomass Yield ◽

Ghg Emissions ◽

Hydrothermal Carbonization ◽

Control Treatment ◽

Miscanthus X Giganteus ◽

Synthetic Fertilizer ◽

Ghg Fluxes

Miscanthus x giganteus (miscanthus), a perennial biomass crop, allocates more carbon belowground and typically has lower soil greenhouse gas (GHG) emissions than conventional feedstock crops, but best practices for nutrient management that maximize yield while minimizing soil GHG emissions are still debated. This study evaluated the effects of four different fertilization treatments (digestate from a biodigester, synthetic fertilizer (urea), hydrochar from the hydrothermal carbonization of digestate, and a control) on soil GHG emissions and biomass yield of an established miscanthus stand grown on abandoned agricultural land. Soil GHG fluxes (including CH4, CO2, and N2O) were sampled in all treatments using the static chamber methodology. Average biomass yield varied from 20.2 Mg ha−1 to 23.5 Mg ha−1, but there were no significant differences among the four treatments (p > 0.05). The hydrochar treatment reduced mean CO2 emissions by 34% compared to the control treatment, but this difference was only statistically significant in one of the two sites tested. Applying digestate to miscanthus resulted in a CH4 efflux from the soil in one of two sites, while soils treated with urea and hydrochar acted as CH4 sinks in both sites. Overall, fertilization did not significantly improve biomass yield, but hydrochar as a soil amendment has potential for reducing soil GHG fluxes.

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