Organic farming practices change the soil bacteria community, improving soil quality and maize crop yields

Background The importance of organic farming has increased through the years to promote food security allied with minimal harm to the ecosystem. Besides the environmental benefits, a recurring problem associated with organic management is the unsatisfactory yield. A possible solution may rely on the soil microbiome, which presents a crucial role in the soil system. Here, we aimed to evaluate the soil bacterial community structure and composition under organic and conventional farming, considering the tropical climate and tropical soil. Methodology Our organic management treatments were composed by composted poultry manure and green manure with Bokashi. Both organic treatments were based on low nitrogen inputs. We evaluated the soil bacterial community composition by high-throughput sequencing of 16S rRNA genes, soil fertility, and soil enzyme activity in two organic farming systems, one conventional and the last transitional from conventional to organic. Results We observed that both organic systems evaluated in this study, have higher yield than the conventional treatment, even in a year with drought conditions. These yield results are highly correlated with changes in soil chemical properties and enzymatic activity. The attributes pH, Ca, P, alkaline phosphatase, and β- glucosidase activity are positively correlated with organic systems, while K and Al are correlated with conventional treatment. Also, our results show in the organic systems the changes in the soil bacteria community, being phyla Acidobacteria, Firmicutes, Nitrospirae, and Rokubacteria the most abundant. These phyla were correlated with soil biochemical changes in the organic systems, helping to increase crop yields. Conclusion Different organic management systems, (the so-called natural and organic management systems, which use distinct organic sources), shift the soil bacterial community composition, implying changes in their functionalities. Also, our results contributed to the identification of target bacterial groups and changes in soil chemical properties and enzymatic activity in a trophic organic farming system, which may contribute to higher crop yields.

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Effects of novel bioorganic fertilizer application on soil enzymes and bacterial community in multi-site rice paddies in China

AMB Express ◽

10.1186/s13568-021-01241-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zuren Li ◽

Jincai Han ◽

Haodong Bai ◽

Di Peng ◽

Lifeng Wang ◽

...

Keyword(s):

Bacterial Community ◽

Field Experiments ◽

Chemical Properties ◽

Soil Bacterial Community ◽

General Function ◽

Rice Paddies ◽

Phylogenetic Groups ◽

Total N ◽

Bioorganic Fertilizer ◽

Soil Bacterial

AbstractApplication of a novel bioorganic fertilizer (BIO) has been effectively used to inhibit weeds in rice paddies. To identify changes in soil bacterial community and enzymes in response to BIO treatments, field experiments were carried out in five major rice-growing areas in China. The dominant phylogenetic groups recorded included Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Acidobacteria. Anaeromyxobacter, Bacteroides, Bifidobacterium, Escherichia- Shigella, Geobacter and Haliangium were significantly different between BIO-treatment and untreated control and aided in general function (R), amino acid transport, metabolism (E) and transcription (K) clusters. The soil chemical properties and enzyme activities were less affected by BIO at these study sites. RDA analysis showed that soil bacterial community had a significant positive correlations among northern latitude, eastern longitude, exchangeable K, total K, total P, soil pH, and total N, except for organic matter, hydrolytic N and extractable P. Overall, our work showed that application of BIO does not alter the main community structure and functional diversity of soil bacteria in rice paddies and should be encouraged for use as a sustainable weed management strategy.

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Effects of Simulated Nitrogen Deposition on the Bacterial Community of Urban Green Spaces

Applied Sciences ◽

10.3390/app11030918 ◽

2021 ◽

Vol 11 (3) ◽

pp. 918

Author(s):

Lingzi Mo ◽

Augusto Zanella ◽

Xiaohua Chen ◽

Bin Peng ◽

Jiahui Lin ◽

...

Keyword(s):

Bacterial Community ◽

Bacterial Diversity ◽

Negative Impact ◽

Bacterial Community Composition ◽

N Deposition ◽

Soil Bacterial Community ◽

Rrna Gene ◽

Soil Dna ◽

Urban Green ◽

Soil Bacterial

Continuing nitrogen (N) deposition has a wide-ranging impact on terrestrial ecosystems. To test the hypothesis that, under N deposition, bacterial communities could suffer a negative impact, and in a relatively short timeframe, an experiment was carried out for a year in an urban area featuring a cover of Bermuda grass (Cynodon dactylon) and simulating environmental N deposition. NH4NO3 was added as external N source, with four dosages (N0 = 0 kg N ha−2 y−1, N1 = 50 kg N ha−2 y−1, N2 = 100 kg N ha−2 y−1, N3 = 150 kg N ha−2 y−1). We analyzed the bacterial community composition after soil DNA extraction through the pyrosequencing of the 16S rRNA gene amplicons. N deposition resulted in soil bacterial community changes at a clear dosage-dependent rate. Soil bacterial diversity and evenness showed a clear trend of time-dependent decline under repeated N application. Ammonium nitrogen enrichment, either directly or in relation to pH decrease, resulted in the main environmental factor related to the shift of taxa proportions within the urban green space soil bacterial community and qualified as a putative important driver of bacterial diversity abatement. Such an impact on soil life induced by N deposition may pose a serious threat to urban soil ecosystem stability and surrounding areas.

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Plant–Soil Feedback In Camellia Oleifera And Mixed Gardenia Jasminoides Ellis–Camellia Oleifera Stands Determined By Soil Bacterial Community Analysis

10.21203/rs.3.rs-849971/v1 ◽

2021 ◽

Author(s):

Yun Wang ◽

Peng Xie ◽

Jiyun She ◽

Aihua Deng ◽

Shaogang Fan

Keyword(s):

Bacterial Community ◽

Chemical Properties ◽

Physicochemical Characteristics ◽

Soil Bacterial Community ◽

Physical And Chemical Properties ◽

Camellia Oleifera ◽

Gardenia Jasminoides ◽

Soil Bacterial ◽

Physical And Chemical ◽

And Chemical Properties

Abstract Purpose: Little is known regarding the combined impact of plant and soil traits on the soil bacterial community. Herein, we assessed physical and chemical properties along with bacterial community structure in soils sampled at different depths (0–20 cm, 20–40 cm, and 40–60 cm) and slope positions (peak, hillside, and bottom), in Camellia oleifera monoculture and mixed Gardenia jasminoides–Camellia oleifera stands. Methods: Soil physicochemical characteristics were determined using standard methods. The composition of soil bacterial communities was evaluated using high-throughput sequencing of the 16S rRNA gene. Results: Soil organic carbon, humus, and total organic contents were higher in G. jasminoides + C. oleifera low-yielding forest than in other stands, however, the NH4+-N levels were significantly lower than that in monoculture. The slope position did not greatly influence soil physical and chemical properties. The dominant bacteria were Proteobacteria, Chloroflexi, Acidobacteria, and Actinobacteria. The alpha and beta diversity and abundance of soil bacterial community were higher in intercropping systems than in monoculture systems. Potassium and nitrogen levels and pH significantly affected the soil microbial community composition. Correlation analysis revealed that alkaline hydrolysable nitrogen and pH were significantly correlated with the input of plant-associated organic matter and dynamic changes of keystone taxa.Conclusion: G. jasminoides improved the physicochemical characteristics of C. oleifera low-yielding soil and greatly affected the soil bacterial community, further improving the soil microecological environment. Therefore, this specific intercropping system is an effective strategy for improving soil health.

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