Intensive pig farming is an important economic activity and generates a large amount of liquid pig manure as a by-product, which is considered a promising resource for the fertilization of tropical soils, characterized as low natural fertility. In an agricultural area under no tillage soybean-corn cropping system, located in southwest of Brazil, an experiment was carried out with different forms of fertilization; that is, organic fertilization with pig manure (17 years) at different rates of application and with mineral fertilization. Regarding the pig manure application rate, with yearly carbon load of 50 m³ ha⁻¹ tended to promote the mineralization of organic matter, with formation of humic substances and to improve the size of aggregates. The use of LPM promoted little soil carbon addition varying of 0.05-3.41 kg ha⁻¹ with 17 years of LPM application and the continuous application of pig tended to be advantageous for the tropical soil, providing a positive carbon balance, which favored the soil and the environment through the rational waste disposal.

Biostimulants are a strategy to minimize the effects of climatic adversities, allowing the seedlings to express more strongly their metabolic capacity and greater development of the root system. The objective was to verify the abil­ity of a biostimulant with Ascophyllum nodosum to increase biometric characteristics in maize crop in the off-sea­son. The test was conducted in randomized block design with four replicates and five treatments, using five doses of the biostimulant, 0.0; 0.25; 0.50; 0.75 and 1.00 liters of product to 100 kg of seeds. Seedlings were evaluated for vigor, length of root and aerial part, dry matter of the root and aerial part and leaf area. The data were submit­ted to ANOVA and regression analysis to verify the behavior of the characteristics due to increasing doses. The doses of biostimulant in seed treatment provided increases in vigor, shoot height, weight of fresh and dry matter of the aerial part and leaf area. The biostimulant derived from Ascophyllum nodosum extract showed potential use in the treatment of corn seeds, and doses of 0.50 and 0.75 L per 100 kg of seeds were the most promising for the early development of maize seedlings.

Soil use and management practices influence the quantity and quality of soil organic matter (SOM). From this perspective, the objective of this work was to evaluate the carbon stock and SOM fractions in a no-tillage (NT) and crop–livestock integration (CL) system in the Cerrado biome. The treatments were divided into four areas, subdivided into an area under NT with 11 years of cultivation, two areas under CL with 5 or 10 years of cultivation, and an area of native vegetation (NV). Undisturbed and disturbed soil (Ferralsols) samples were collected in layers 0.0–0.1, 0.1–0.2, 0.2–0.4, and 0.4–0.6 m for the evaluations of soil properties, including bulk density, weighted mean diameter, clay content, carbon stock, carbon stock of light and mineral fractions, humification rate, and carbon management index. The results obtained suggest that the environments with the highest conservation of the physical properties of the soil are those that contain the highest levels of stable C. The main mechanism for C protection in the systems evaluated was mainly associated with physical protection, promoted by soil aggregates, capable of keeping C protected, and mitigation of C into the atmosphere. The values of the carbon management index in the agriculture areas were >100, indicating that these production systems could approach the soil quality of the native vegetation reference system.

Crop yield decrease is the main concern when a pathogen or plague is identified in an agriculture field. Thus, part of this issue can be attributed to plant-parasitic nematodes (PPNs), such as Meloidogyne species, due to, most of the time, the hard diagnosis, and non-specific symptoms. Its management is mainly based on chemical pesticides, followed by a few potential biological control agents, and the management system. Therefore, this study aimed to evaluate the effects of biological agents in Meloidogyne incognita control in different soil systems. For that, two biological products were chosen, Trichoderma asperellum BV10 and Bacillus amyloliquefaciens BV03, and soils were sampled from three different managements systems: (i) soybean no-tilled system at Goiás state, Brazil; (ii) forest soil at Goiás state, Brazil, and (iii) soybean conventional managed system at Mato Grosso do Sul state, Brazil. Biocontrol and growth promotion effects, volatile organic compounds (VOCs) and soil respiration were determined in vegetation house and laboratory, respectively. As a result, both BV10 and BV03 had significant nematode control activity, comparing to control treatment, in all the three soils systems. Plus, the number of immobile nematodes by potential VOCs had significant increase when BV03 was applied, while the application of BV10 agent raised the soil respiration rate. In conclusion, both biocontrol agents presented great efficiency in control M. incognita, with better performance of BV03. Lastly, more studies must be done to elucidate how the resident soil microbiome can influence on biocontrol agent establishment and performance, as well as the consequence of the application of biological products on soil microbiome network.