Search Results (22)

The adoption of integrated production systems may be an alternative for improving soil health and increasing production. The aim of this study was to evaluate changes in soil fertility and microbial metabolism, as well as the impact on soybean productivity, in different conservation systems in contrast to the conventional system, after four years of adopting integrated systems. The experimental design used was a randomized block design with seven treatments and three replications. The treatments included different species of forage grasses, the no-tillage soybean–maize system in succession, and conventional planting. It was found that after four years of using integrated systems, the changes in soil health were small, indicating that these effects are seen over the long term. Soil chemistry showed that the use of forage grasses is essential for improving fertility, with a focus on phosphorus, potassium, magnesium, sulfur, base sum, and cation exchange capacity, which is reflected in the high soybean productivity in treatments with forage grasses, especially the use of Paiaguás and Piatã grasses. Even with slow changes in soil health, adopting integrated systems is an important practice for tropical sandy soils, as visible improvements in fertility were observed, which are reflected in productivity gains. Full article

The Mediterranean region faces intensified climate change effects, increasing irrigation demands to sustain crop yields and increasing pressure on water resources. Adaptive management strategies such as conservation agriculture (CA) offer potential benefits for soil quality and water use efficiency. However, there is limited research on the short-term effects of this farming system under irrigated Mediterranean climatic conditions. This study aimed to explore the short-term impacts of conservation agriculture (no tillage, cover crops and crop rotation) on the soil properties, water flows and crop and water productivity in a French Mediterranean agrosystem of irrigated field crops, using a multifactorial approach. From 2021 to 2023, maize, sorghum and soybean were grown successively under either conventional tillage (CT) or conservation agriculture (CA), combined with sprinkler irrigation, subsurface drip irrigation or non-irrigated conditions. The dynamics of the surface soil properties (bulk density, penetration resistance, soil temperature), water flows (infiltration, soil evaporation) and agronomic indicators (leaf area index, crop yield, water productivity) were measured across the three cropping seasons. In the pedoclimatic conditions of the study, CA was shown to clearly impact the soil properties, water flows and crop yields, from the first year of adoption. CA practices caused an increased bulk density and soil resistance penetration, leading to decreased quasi-steady ponded infiltration in the surface horizon, particularly in the CA–subsurface drip and CA–non-irrigated conditions. These effects were also reflected in the leaf area index, crop yield and water productivity, with CA showing lower values compared to CT. Crop residues in CA reduced soil evaporation, particularly under sprinkler irrigation. However, this benefit diminished as the residues decomposed, leading to soil evaporation rates comparable to those observed in CT. Agronomic indicators were better under sprinkler irrigation than under subsurface drip irrigation. Overall, compaction emerged as a significant challenge in the adoption of CA, considering its negative impact on crop yields. Full article

Modern agriculture faces the challenge of increasing production without expanding cultivated areas, promoting sustainable practices that ensure food security and environmental preservation. Integrated crop–livestock systems (ICLSs) stand out as an effective strategy, diversifying and intensifying agricultural production in a sustainable manner, ensuring adequate soil cover, and improving nutrient cycling efficiency. Thus, this study aimed to explore and compare integrated crop–livestock systems with Zuri guinea grass (Panicum maximum cv. BRS Zuri) and Quênia guinea grass (Panicum maximum cv. BRS Quênia) against the conventional soybean/maize succession method in a tropical region, and how these systems affect biomass decomposition, C:N ratio, nutrient cycling, and fertilizer equivalents. A field experiment was conducted in two phases: the first in the second-crop season and the second in the main season, using a randomized block design with four replicates. The treatments consisted of two ICLS systems, one with Zuri and Quênia guinea grasses established after soybean, and a succession system with maize established after soybean. The results indicated that Quênia guinea grass showed greater desiccation efficiency, with an injury rate of 86.5% at 21 days, 8.5% higher compared to Zuri guinea grass. In terms of biomass, Zuri and Quênia guinea grasses had average productions of 7021.1 kg ha⁻¹, which was 43.25% higher compared to maize biomass. The biomass decomposition of the grasses was faster due to their lower C:N ratio, resulting in greater nutrient release into the soil. Both forage grasses (Zuri and Quênia guinea grasses) are suitable for integrated crop–livestock systems, as they showed similar biomass production and nutrient accumulation. Soybean yield was not influenced by the different cropping systems, showing similar results between the biomass of Zuri and Quênia guinea grasses and maize. However, grass biomass enriches the soil more through the return of fertilizer equivalents, which in future studies could be considered for the reduction of mineral fertilizers, ensuring greater sustainability of agricultural systems. Full article

Ensuring global food security amid mounting challenges, such as population growth, disease infestations, resource limitations, and climate change, is a pressing concern. Anticipated increases in food demand add further complexity to this critical issue. Plant pathogens, responsible for substantial crop losses (up to 41%) in major crops like wheat, rice, maize, soybean, and potato, exacerbate the situation. Timely disease detection is crucial, yet current practices often identify diseases at advanced stages, leading to severe infestations. To address this, remote sensing and Hyperspectral imaging (HSI) have emerged as robust and nondestructive techniques, exhibiting promising results in early disease identification. Integrating machine learning algorithms with image data sets enables precise spatial–temporal disease identification, facilitating timely detection, predictive modeling, and effective disease management without compromising fitness or climate adaptability. By harnessing these cutting-edge technologies and data-driven decision-making, growers can optimize input costs while achieving enhanced yields, making significant strides toward global food security in the face of climate change risks. This review will discuss some of the foundational concepts of remote sensing, several platforms used for remote sensing data collection, successful application of the approach, and its future perspective. Full article

The biological degradation of plant residues in the soil or on the soil surface is an integral part of the natural life cycle of annual plants and does not have adverse effects on the environment. Crop straw is characterized by a complex structure and exhibits stability and resistance to rapid microbial decomposition. In this study, we conducted a microcosm experiment to investigate the dynamic succession of the soil microbial community and the functional characteristics associated with lignocellulose-degrading pathways. Additionally, we aimed to identify lignocellulose-degrading microorganisms from the straw of three crop species prevalent in Northeast China: soybean (Glycine max Merr.), rice (Oryza sativa L.), and maize (Zea mays L.). Our findings revealed that both the type of straw and the degradation time influenced the bacterial and fungal community structure and composition. Metagenome sequencing results demonstrated that during degradation, different straw types assembled carbohydrate-active enzymes (CAZymes) and KEGG pathways in distinct manners, contributing to lignocellulose and hemicellulose degradation. Furthermore, isolation of lignocellulose-degrading microbes yielded 59 bacterial and 14 fungal strains contributing to straw degradation, with fungi generally exhibiting superior lignocellulose-degrading enzyme production compared to bacteria. Experiments were conducted to assess the potential synergistic effects of synthetic microbial communities (SynComs) comprising both fungi and bacteria. These SynComs resulted in a straw weight loss of 42% at 15 days post-inoculation, representing a 22% increase compared to conditions without any SynComs. In summary, our study provides novel ecological insights into crop straw degradation by microbes. Full article

Chenopodium ambrosioides L. is an invasive plant native to the Neotropics that has seriously threatened the ecological security of China, and allelopathy is one of the mechanisms underlying its successful invasion. Maize (Zea mays L.) and soybean (Glycine max (L.) Merr.), as the main food crops, are usually affected by C. ambrosioides in their planting areas. The purpose of this study was to investigate the ultrastructure, autophagy, and release-related gene expression of receptor plant root border cells (RBCs) after exposure to volatile oil from C. ambrosioides and its main component α-terpene, which were studied using maize and soybean as receptor plants. The volatiles inhibited root growth and promoted a brief increase in the number of RBCs. As the volatile concentration increased, the organelles in RBCs were gradually destroyed, and intracellular autophagosomes were produced and continuously increased in number. Transcriptomic analysis revealed that genes involved in the synthesis of the plasma membrane and cell wall components in receptor root cells were significantly up-regulated, particularly those related to cell wall polysaccharide synthesis. Meanwhile, polygalacturonase and pectin methylesterases (PME) exhibited up-regulated expression, and PME activity also increased. The contribution of α-terpene to this allelopathic effect of C. ambrosioides volatile oil exceeded 70%. Based on these results, receptor plant root tips may increase the synthesis of cell wall substances while degrading the intercellular layer, accelerating the generation and release of RBCs. Meanwhile, their cells survived through autophagy of RBCs, indicating the key role of RBCs in alleviating allelopathic stress from C. ambrosioides volatiles. Full article

Soybean is one of the most widely grown crops in the world and technologies are increasingly needed to increase productivity without impacting environmental degradation. In this context, the aim was to evaluate the action of forage plants of the genus Brachiaria sp. in crop–livestock integration on physical soil, agronomic and environmental aspects of soybean cultivation. The experiment was conducted in a subdivided plot design with seven integrated systems corresponding to the previous cultivation of Paiaguas palisadegrass, Xaraes palisadegrass and Ruziziensis grass in monocropping and intercropped with maize, as well as maize in monocropping. In the subplots, two grass management systems were evaluated: free growth and a grazing simulation cut. The bulk density and least limiting water range were assessed using soil samples and, after the pastures were desiccated when the soybean crop was planted, straw decomposition and plantability. A soil physics diagnosis by the bulk density and least limiting water range showed that the Paiaguas palisadegrass and Xaraes palisadegrass improved the soil environment due to biological soil loosening. The remaining mulch biomass did not affect soybean sowing and the adoption of Brachiaria sp. grass in the off-season, in addition to contributing to the provision of environmental services, and did not compromise grain productivity in succession. Full article

Communication through airborne volatile organic compounds (VOCs) and root exudates plays a vital role in the multifarious interactions of plants. Common ragweed (Ambrosia artemesiifolia L.) is one of the most troublesome invasive alien species in agriculture. Below- and aboveground chemical interactions of ragweed with crops might be an important factor in the invasive species’ success in agriculture. In laboratory experiments, we investigated the contribution of intra- and interspecific airborne VOCs and root exudates of ragweed to its competitiveness. Wheat, soybean, and maize were exposed to VOCs emitted from ragweed and vice versa, and the adaptation response was measured through plant morphological and physiological traits. We observed significant changes in plant traits of crops in response to ragweed VOCs, characterized by lower biomass production, lower specific leaf area, or higher chlorophyll contents. After exposure to ragweed VOCs, soybean and wheat produced significantly less aboveground dry mass, whereas maize did not. Ragweed remained unaffected when exposed to VOCs from the crops or a conspecific. All crops and ragweed significantly avoided root growth toward the root exudates of ragweed. The study shows that the plant response to either above- or belowground chemical cues is highly dependent on the identity of the neighbor, pointing out the complexity of plant–plant communication in plant communities. Full article

Currently, the development of genome editing (GE) tools has provided a wide platform for targeted modification of plant genomes. However, the lack of versatile DNA delivery systems for a large variety of crop species has been the main bottleneck for improving crops with beneficial traits. Currently, the generation of plants with heritable mutations induced by GE tools mostly goes through tissue culture. Unfortunately, current tissue culture systems restrict successful results to only a limited number of plant species and genotypes. In order to release the full potential of the GE tools, procedures need to be species and genotype independent. This review provides an in-depth summary and insights into the various in vitro tissue culture systems used for GE in the economically important crops barley, wheat, rice, sorghum, soybean, maize, potatoes, cassava, and millet and uncovers new opportunities and challenges of already-established tissue culture platforms for GE in the crops. Full article

The continuous rice–wheat cropping system in South Asia has caused irreversible environmental damage, raising concerns about the long-term sustainability of the region’s agricultural systems. To address this issue, farm experiments were conducted for two successive years (2019–20 and 2020–21) to assess the impact of different cropping systems under conservation agriculture (CA) practices on the yield, productivity, and profitability of wheat. Results showed that the highest grain yield of wheat was observed in scenarios Sc6, Sc4, and Sc2, which involved full CA permanent-bed soybean (PB)–permanent-bed wheat (PB)–permanent-bed summer moong (PB), full CA permanent-bed maize (PB)–permanent-bed wheat (PB)–permanent-bed summer moong (PB), and partial CA puddled transplanted rice–Happy Seeder wheat–zero-till summer moong (ZT). Additionally, the highest irrigation water productivity (IWP), wheat grain macronutrient uptake, net return, and benefit–cost ratio (B:C ratio) were recorded under Sc6, full CA permanent-bed soybean (PB)–permanent-bed wheat (PB)–permanent-bed summer moong (PB) compared to farmers’ practice puddled transplanted rice (PTR)–conventional-till wheat–summer moong (Sc1) during both years. The system productivity also increased in scenarios Sc2, Sc4, and Sc6 (by 9.72%, 9.65%, and 14.14% in the first year and 10.68%, 14.14%, and 15.55% in the second year) compared to Sc1—farmers’ practice puddled transplanted rice (PTR)–conventional-till wheat–summer moong, Sc3—farmers’ practice fresh-bed maize (FB)–conventional-till wheat–summer moong, and Sc5–farmers’ practice fresh-bed soybean (FB)–conventional-till wheat (CT)–summer moong. The findings suggest that the conservation agriculture soybean–wheat–summer moong (Sc6) on permanent-bed cropping systems with inclusion legumes can be a potential option to enhance yield attributes, productivity, and profitability, as well as the sustainability of natural resources in the region while decreasing environmental footprints. Full article

In Brazil, grain crops in no-till soybean–maize succession have reduced biodiversity and carbon input into soil. Intercropping is a promising approach to address these problems. This study aimed to evaluate the microbiological quality of soil in conventional and intercropping systems in soybean–maize succession, depending on tropical grass and nitrogen fertilizer uses. The treatments were arranged in a randomized complete block design and a split plot scheme, with four replications. The main plots consisted of the following cropping systems: soybean monoculture–maize monoculture; soybean intercropped with Aruana Guinea grass (Megathyrsus maximum cv. Aruana)–maize intercropped with Aruana Guinea grass; and soybean intercropped with Congo grass (Urochloa ruziziensis cv. Comun)–maize intercropped with Congo grass. The subplots consisted of nitrogen rates (0, 50, 100, and 150 kg ha⁻¹) applied as side-dressing in rows of maize and tropical grass in the autumn–winter season. Our results showed that maize or soybean intercropped with tropical grasses and adequate nitrogen rates favored the entry of microbial carbon and nitrogen, stimulated enzymatic activity, and reduced C-CO₂ loss. However, the excess nitrogen supply can nullify the benefits of the intercropping systems. We concluded that the intercropping systems can improve soil microbiological quality in a short time with adequate nitrogen supply. Full article

In no-tillage systems, soil compaction has caused negative impacts on crop productivity and soil quality. The objective of this study was to evaluate the soil physical quality after different crops of the second season: maize, sorghum, and millet in compacted and uncompacted soils, in addition to evaluating the performance of soybean in succession in Rhodic Ferralsol under no-tillage (NT) in the Brazilian Cerrado biome. A field experiment was conducted during the second season of 2019 and the first season of 2019/20 in Rio Verde, Brazil. The experimental design used randomized blocks in a 3 × 2 factorial scheme, with six replications. The first factor corresponded to the cultivation of maize, sorghum, and millet; the second factor was the cultivation of these crops in compacted and uncompacted soils. The physical properties of the soils in the 0–0.1 and 0.1–0.2 m depth layers were evaluated after the second season of cultivation, in addition to the agronomic characteristics of the soybean cultivated in succession. The results indicate that the compaction influenced the soil physical quality, mainly in the 0.1–0.2 m layer, reflecting a decrease in the performance of the soybean crop (i.e., the plant height, number of pods per plant, and grain yield). The use of the second-season crop of millet improved the soil physical properties of penetration resistance and macroporosity and improved the water/air relation. The use of millet provided a reduction of up to 20% in the soil penetration resistance. About 10% more soybean was produced after cultivation in succession to millet compared to maize and sorghum. Full article

Interest in fall–winter species options for rotation with soybean (Glycine max (L.) Merr.) has arisen; however, little is known about how they can affect the performance of subsequent soybean under a no-tillage system in tropical environments. Our objective was to evaluate the leaf nutrient concentration, aboveground dry matter (DM) accumulation, macronutrient uptake, yield components, and seed yield of soybean cropped in succession to different crop species. Consequently, a field experiment was conducted during three consecutive growing seasons in Botucatu, São Paulo State, southeastern Brazil. The experiment was arranged in a randomized complete block design with four replicates. The treatments consisted of the cultivation of five crops (crambe (Crambe abyssinica Hochst. ex. R.E. Fries), maize (Zea mays L.), safflower (Carthamus tinctorius L.), sorghum (Sorghum bicolor (L.) Moench), and sunflower (Helianthus annuus L.)) in rotation with soybean, in addition to plots that lie fallow (spontaneous weeds) in the soybean off-season, totaling six treatments. Letting plots lie fallow during the off-season reduced the DM accumulation, nutrient uptake, and seed yield of the soybean crop in succession. Preceding cultivation of fall–winter crambe or sunflower favored the uptake of P, K, Ca, Mg, and S by the following soybean crop. The cultivation of sorghum, safflower, and crambe as fall–winter crops also increased the seed yield of subsequent soybean (from 12 to 18% on the average of three growing seasons) compared to fallow plots. The highest increases in soybean seed yield were found in succession to maize (37%) or sunflower (45%) in the second and third growing seasons, respectively. Full article

Forage grasses cultivation in production system with soybean and maize is an alternative to improve tropical weathered soils quality in Brazil. The aim of the study was to evaluate the effects in the production systems involving cultivation of Urochloa brizantha cv. Piatã, in monoculture or in succession with soybean and maize crops, on organic matter and structuring of soil in Brazilian savanna. The experiment was implemented in the 2010/2011 season. The treatments consisted of nine production systems and a native forest (savanna) as a reference area. In March 2017, soil sampling was carried out for C and N analysis, physical and chemical fractionation of SOM and aggregate stability. Production systems influenced total organic carbon (TOC) and aggregate stability, mainly in the surface layers, leading to changes in SOM quality. TOC was 31% lower in monoculture soybean production system, when compared to native savanna area, in the 0.00–0.20 m layer. The agricultural production systems influence organic matter quality and soil aggregates stability. For the Brazilian savanna conditions, grain cultivation systems under no-tillage that integrate Urochloa brizantha cv. Piatã contribute to the soil quality improvement. Soybean monoculture generally provides worse soil quality indices compared to other agricultural production systems. Full article

The success of the seed-metering device of a seeder determines the quality seeding and final plant stand. The adjustment of the optimal vacuum pressure of air-suction-type seed-metering devices is a key factor affecting the success of seed-metering devices. The optimal value of vacuum of the seed-metering device should be adjusted in relation to the physical properties of the seed before seeding in the field. This research was carried out to estimate the optimal value of vacuum pressure of an air-suction seed-metering device of a precision seeder by using an artificial neural network method. Training of the network was performed by using a Levenberg–Marquardt (LM) learning algorithm. Training and testing were carried out using Matlab software. The inputs were physical properties of seeds such as surface area, thousand kernel weight, kernel density and sphericity. Optimum vacuum pressures were determined for soybean, maize, cucumber, melon, watermelon, sugarbeet and onion seeds in laboratory. Surface area, thousand kernel weight, kernel density and sphericity of seeds varied from 0.05 to 0.638 cm², 4.4 to 322.4 g, 0.43 to 1.29 g cm⁻³ and 42.8 to 85.75%, respectively. The optimal vacuum pressure was determined as 1.5 kPa for onion; 2.0 kPa for sugarbeet; 2.5 kPa for melon and watermelon; 3.0 kPa for soybean; and 4.0 kPa for maize seeds. A trained program using an artificial neural network could satisfactorily estimate the optimum value of vacuum pressure of the air-suction type seed-metering device of precision seeders with a prediction success (R²) of 0.9949 for both linear and polynomial regressions. Full article