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

Author(s)

Durrer, Ademir ^[1] ; Gumiere, Thiago ^[2] ; Zagatto, Mauricio Rumenos Guidetti ^[1] ; Feiler, Henrique Petry ^[1] ; Silva, Antonio Marcos Miranda ^[1] ; Longaresi, Rodrigo Henriques ^[3] ; Homma, Sergio K. ^[3] ; Cardoso, Elke J. B. N. ^[1]

Affiliation

^[1] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Soil Sci Dept, Piracicaba, SP - Brazil

^[2] Laval Univ, Dept Soil & Agr Engn, Quebec City, PQ - Canada

^[3] Mokiti Okada Res Ctr, Ipeuna, SP - Brazil

• Document type: Journal article
• Source: PeerJ; v. 9, SEP 23 2021.
• Web of Science Citations: 2

Abstract

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 beta-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. (AU)

• FAPESP's process: 17/18994-3 - Relationship between cropping systems and soil microorganisms: effects on microbiota and plant development promoters
• Grantee: Ademir Durrer Bigaton
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/13436-8 - Mitigation of water stress in maize (Zea mays L.) after arbuscular mycorrhizal fungi and growth promoting rhizobacteria inoculation
• Grantee: Antonio Marcos Miranda Silva
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 16/18944-3 - Climatic changes and energetic efficiency in agriculture: focusing on hydric stress, organic management and soil biology
• Grantee: Elke Jurandy Bran Nogueira Cardoso
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants