Soybean Grain Research Articles

Management tendencies and needs: a joint proposal to maximize soybean grain yield

The objective of the study was to evidence efficient management strategies in order to maximize soybean grain yield. The experiments took place at Centro de Pesquisas e Resultados Agronômicos das Missões (CPRAM), located in Entre - Ijuís - Rio Grande do Sul, Brasil. Three experiments were carried out in a randomized block design with four replications per treatment. The experiments were based on soybean crop management. Soil cover with vetch enhanced soybean grain yield. The cultivar BRS 5804RR® presented the best productive performance in the arrangements of 7 and 11 seeds m-1. Artificial defoliation did not influence soybean grain yield.

Isoflavone profile identification and storage stability of different soybean genotypes sown at standard and late dates in a subtropical climate

The genetic variability of soybean grains allows its grow in different regions, where the adaptability of the genotypes to environments, and sowing times can affect the isoflavone profile and post-harvest conservation. Thus, the objective was to evaluate the genotype effects, sowing date, and storage time on technological properties and isoflavone profile of soybean. For this, it was used the soybean genotypes BMX LANÇA IPRO, NA 5909 RG, BMX ATIVA RR, and BMX GARRA IPRO, cultivated in standard (October 25th) and a late sowing date (November 15th). Analyzes performed in the present study were acidity, lipase activity, soluble protein, germination, electric conductivity, soybean defects, colorimetric profile, and isoflavone profile. Higher levels of isoflavones were found in the BMX GARRA IPRO genotype. The genotype BMX ATIVA RR when cultivated in late sowing date showed a reduced isoflavones contents. The NA 5909 RG genotype showed lower adaptability to the conditions of the environment where it was cultivated and higher susceptibility to prolonged storage, showing higher values of acidity, lipase activity, and lower values of soluble protein and germination. The BMX LANÇA IPRO genotype showed higher adaptability to the conditions of the environment where it was cultivated and to prolonged storage, showing higher values of soluble protein, and germination, and lower values of electrical conductivity, and soybean defects, proving the effect of genotype on soybean growing conditions. A reduction in soluble protein, germination, b*-value, and L*-value and an increase in acidity, lipase activity, electrical conductivity, and fermented grains during storage were observed.

Foliar Application of Selenium Associated with a Multi-Nutrient Fertilizer in Soybean: Yield, Grain Quality, and Critical Se Threshold.

Selenium uptake and its content in soybean grains are affected by Se application methods. This study evaluated the impact of Se foliar application combined with a multi-nutrient fertilizer (MNF) on soybean, establishing a Se threshold to better understand the relationship between Se content in grains and yield of two genotypes (58I60 Lança and M5917). Two trials were conducted in a 4 × 2 factorial design: four Se rates (0, 10, 40, 80 g Se ha-1) and two methods of foliar Se application (Se combined or not with MNF). Foliar fertilizers were applied twice, at phenological stages of beginning of pod development and grain filling. Grain yield increased with the application of MNF, yet Se rates increased Se contents linearly up to 80 g Se ha-1, regardless of the use of MNF. Lança and M5917 genotypes had grain Se critical thresholds of 1.0 and 3.0 mg kg-1, respectively. The application of Se favored higher contents of K, P, and S in grains of genotype Lança and higher contents of Mn and Fe in grains of genotype M5917. Our findings highlight the importance of addressing different Se fertilization strategies as well as genotypic variations when assessing the effects of Se on soybean yield and grain quality.

The Effect of Some Elements of Cultivation in Stubble on the Glycine max Performance

In the irrigation conditions of Azerbaijan, the cultivation of Glycine max in stubble fields after harvesting the barley crop along with spring sowing is also economically very important. Sowing in stubble fields makes it possible to obtain additional grain yield and fodder from a single area, and to use reclamation facilities efficiently. At this time, the soil is provided with organic matter for autumn planting, and at the same time salinization is prevented, soil erosion and weed control issues are fully resolved. Cultivation of stubble field crops in large farms increases the possibilities of more efficient use of labor force, irrigation networks, agricultural machinery and equipment. During the conducted research, different results were obtained regarding the effect of different irrigation regimes and fertilizer rates on soybean grain yield. The resulting productivity depended on the plant coverage factor, leaf surface area, changes in wet and dry biomass. The smallest indicator of the yield was 10.0 centners in the variant with soil moisture of 60% before irrigation, and the highest indicator was 25.8 cwt/ha in the variant of the fertilizer rate calculated when the soil moisture was 80%, which is the same as the yield obtained from the autumn sowing of barley of the previous year (39 cwt/ha) together, it is equal to the yield of 67.9 cwt/ha from 1 hectare of land in one year.

Prediction of soybean yield cultivated under subtropical conditions using artificial neural networks

AbstractMathematical models that incorporate biotic and abiotic attributes are important tools for improving fertilizer use efficiency and reducing production costs for soybean [Glycine max (L.) Merrill] crop. In this study, artificial neural networks (ANNs) were used to estimate soybean grain yield (GY) under subtropical conditions in Brazil from plant morphological and nutritional data collected from 16 cultivars in two growing seasons. The ANNs were adequately trained, with a mean squared error of approximately 10−5 between the outputs obtained (via ANN) and desired (via experimental field), equivalent to a mean percentage error of 70.1 kg ha−1 (1.6%), confirming their efficacy as a tool to estimate GY. Smaller plant height, higher foliar calcium, magnesium and chlorophyll concentrations, and greater numbers of grains per pod and branches per plant were associated with higher GY, whereas oil content, crude protein content, and foliar manganese and potassium concentrations had no predicted effects on GY.

Topping at the Seedling Stage Changes the Plant Morphology and Yield of Unbranched Type Soybean

The crop will be free from the control of apical dominance and the axillary buds will develop into branches after topping. However, there are relatively few studies on this subject of soybean. In order to further improve soybean grain yield, unbranched type high-yield soybean variety was used as test material, and the effects of topping at the first trifoliate stage on soybean plant growth, dry matter accumulation, yield and yield components of five planting densities [15 (D1), 18 (D2), 21 (D3), 25 (D4) and 30 (D5) × 104 plants ha−1] were systematically investigated in this study. The results showed that, the dry matter accumulation increased after topping. Flower number per plant, seed number per plant, pod number per plant, and single-plant yield decreased in conventional-cultivation planting density (D4, topping), but they all increased as the planting density was reduced. D2 achieved the highest yield, with 100-seed weight and yield increased by 8.92% and 5.90% compared to CK (D4, nontopping). The number of branches per plant was significantly and positively correlated with podding node number per plant, flower number per plant, pod number per plant, and seed number per plant. This study demonstrates that the more branches formed after topping, the more conducive to increasing the flower number per plant, pod number per plant under lower density.

Late postemergence glufosinate‐based programs for glyphosate‐resistant Palmer amaranth control in dicamba/glufosinate/glyphosate‐resistant soybean

AbstractGlyphosate‐resistant (GR) Palmer amaranth (Amaranthus palmeri S. Watson) is widespread in the Central Great Plains. Introduction of newly developed dicamba/glufosinate/glyphosate (DGG)‐resistant soybean varieties allows postemergence (POST) applications of dicamba and glufosinate for in‐season control of GR Palmer amaranth. Limited information exists on the effectiveness of glufosinate applied late‐POST for tall (70–90 cm) GR Palmer amaranth control in DGG‐resistant soybean. The objectives of this study were to (1) determine the effectiveness of late‐POST glufosinate‐based programs for GR Palmer amaranth control, and (2) determine the impact of those programs on soybeans grain yields. Ten glufosinate‐based programs were tested in a field study at Kansas State University Agricultural Research Center near Hays, Kansas. Results indicated that single (655 or 737 g ha−1) and all sequential (594 followed by [fb] 594, 655 fb 594, and 737 fb 594 g ha−1) applications (7‐days apart) of glufosinate provided 87%–93% control of GR Palmer amaranth 28 days after last POST (DALPOST). Palmer amaranth control with single late‐POST application of glufosinate (594 g ha−1) or glufosinate plus S‐metolachlor did not exceed 84% at 28 DALPOST. Majority of the evaluated programs reduced shoot dry weights of GR Palmer amaranth by 83%–91%. The least control (11%) and shoot dry weight reduction (33%) of GR Palmer amaranth were observed with glyphosate fb glyphosate. Glufosinate‐based programs resulted in soybean grain yield of 626–701 kg ha−1. These results conclude that glufosinate applied late‐POST may provide effective control of tall GR Palmer amaranth in DGG‐resistant soybeans.

Influence of Manures on Some Soil Fertility Properties, Yield and Agronomic Efficiencies of Soybean (Glycine max) on Degraded Acid Soil

Aluminum toxicity is a major limitation to leguminous crop production in acidic soils but mineral and organic fertilizer applications could ameliorate the condition. Thus, the focus of this study was to evaluate the influence of manures on post-harvest soil fertility quality, yield and agronomic efficiencies of soybean (Glycine max). The study had six fertilizer treatments: poultry manures, rabbit manures, pig manures, sheep manures, cattle manures, single super phosphate and the control (no soil additive) laid in a Completely Randomized Design (CRD), with four replicates. The experiment was conducted at the greenhouse of the Wesley University, Ondo, Nigeria. The treatments were applied at the rate of 40 kg P205ha-1 and the effects of treatments on yield parameters (biomass, grain yield and total dry weight), relative agronomic efficiencies, as well as soil fertility status were observed. Data analysis using ANOVA at 5% level of probability showed the application of poultry manure to have enhanced soybean grain yield and yield component. Poultry manure treatment had the highest mean total dry weight of 11.5 g while SSP resulted in the lowest yield (4.7g). The efficiency of available P released from the applied poultry manure was 2 times higher than the referenced single super phosphate fertilizer in Ondo. Poultry manure application again had higher RAEDSW than to chemical fertilizer. Thus, applications of poultry or pig manures at 40 kg P205ha-1 could be excellent materials as alternatives to mineral fertilizer (single super phosphate) for improving soil fertility, yield of soybean and its agronomic efficiencies.

Development of combine harvester adaptive devices for obtaining high-quality seeds when soybeans harvesting

In increasing soybean production, an important role is given to reducing indirect losses from grain crushing, which adversely affect the quality of seeds, especially when harvesting and processing crops. The impossibility of achieving the optimal mode of operation of the combine at soybean harvesting is due to the peculiarity of the physical and mechanical properties of soybeans. The purpose of the research is to increase the efficiency of the soybean grain harvesting technology based on the development of adapting devices to the combine to obtain the maximum yield of the first fraction of high-quality seeds, followed by their use in sowing without part-time processing (except for pre-sowing etching). The studies were carried out using the modernized Yenisei-1200 combine during the harvesting period 2021-2022 on the experimental field of the Federal State Budgetary Institution of the Federal Research Center of the All-Russian Research Institute of Soybeans. Modernization of the combine makes it possible to collect 60% of high-quality soybean seeds with a low content of weed impurity in a separate section of its bunker. Ripened soybean seeds are soaked in soft modes of operation of the first threshing drum, a separate collection of which increases field germination and biological yield of the first seed fraction. Application of sieves of upper sieve mill of combine harvester cleaning with increased length of blinds petals up to 70 mm together with increased air flow ensures purity of seeds of the first fraction at the level of the first class of sowing standard. Mechanical damage to soybean seeds of the first fraction, which is 4.2%, does not exceed the established standard for crushing and microdepositing combines (5%). The use of seeds of the first fraction in sowing without additional processing reduces the indirect losses of soybeans and, accordingly, the costs of seed production.Ripened soybean seeds are soaked in soft modes of operation of the first threshing drum, a separate collection of which increases field germination and biological yield of the first seed fraction. Application of sieves of upper sieve mill of combine harvester cleaning with increased length of louver petals up to 70 mm together with increased air flow ensures purity of seeds of the first fraction at the level of the first class of sowing standard. Mechanical damage to soybean seeds of the first fraction, which make 4.2%, does not exceed the established standard for crushing and micro damage combines (5%). Using the seeds of the first fraction in sowing without working, reduces indirect losses of soybeans and, accordingly, the costs of seed production.

National winter oilseeds review for potential in the US Mid‐South: Pennycress, Canola, and Camelina

AbstractWinter oilseeds are cool season Brassica crops currently being grown in the upper Midwest and North‐West of the United States. They have the potential to function as dual crops when grown in rotation with corn, soybean, and small grains. They provide many of the benefits of typical cover crops over winter, with the added benefit of extra revenue to growers who sell the seeds for uses such as biofuel, industrial products, human consumption, or animal feed. This review gathers current agronomic and industrial use information about canola (Brassica napus L.), camelina [Camelina sativa (L.) Crantz], and pennycress (Thlaspi arvense L.). Currently, most research involving these crops is specific to the Midwest. This review also poses questions regarding how these crops could be adapted to grow in the Mid‐South, with further research being necessary in several areas before promoting adoption in the region.

Influence of cover crops on soybean yield and partial returns as an alternative to double‐crop soybean in Arkansas

AbstractThe number of hectares dedicated to winter wheat (Triticum aestivum L.) in the southern United States has been trending downward for almost a decade, presenting an opportunity for producers to utilize alternatives in their soybean [Glycine max (L.) Merr.] rotations, such as winter cover crops. A study was established to compare the cover crops to traditional cropping systems by determining the effect each had on a successive soybean crop and to examine partial economic returns. Cropping systems implemented were winter fallow, winter wheat, and seven cover crop treatments, including cereal rye (Secale cereale L.), black‐seeded oat (Avena sativa L.), barley (Hordeum vulgare L.), Austrian winter pea (Pisum sativum L.), blue lupin (Lupinus angustifolius L.), Blend 1 (cereal rye, crimson clover [Trifolium incarnatum L.], seven‐top turnip [Brassica rapa L.]). and Blend 2 (black‐seeded oats and Austrian winter pea). The winter cropping system did not affect the soybean plant population (p = 0.32). Soybean grain yield varied among the different winter cropping systems (p < 0.01) with yields ranging from 3346 to 3906 kg ha−1. The soybean double‐crop system ($1383.02 ha−1) and soybean following winter cover crops ($1239–1380 ha−1) produced similar partial returns but both were greater than soybean following winter fallow ($1217.81 ha−1) (p < 0.01). Soybean yields and partial returns were the highest when following Blend 2. Results of this study showed that winter cover crops can provide an adequate alternative to both winter fallow and traditional winter wheat soybean double‐crop systems in the mid‐southern United States.

Efficiency of use of the modern gene pool in the production of cereals and legumes

The authors in the article provided data on the use of different varieties and hybrids of cereals and legumes. The experiments were carried out in the forest steppe of the Novosibirsk Priobya region in 2020–2022. The studies were conducted on the leached chernozem of the Praktik EEF (Educational and Experimental Farm) of the Novosibirsk Region and CJSC Livestock Breeding Farm Irmen of the Ordynsky District Novosibirsk Region. Also, the authors conducted experiments in the steppe zone on the southern chernozem of Nadezhda LLC of the Bagansky district and on grey forest medium loamy soil of the Education and Production Farm (EPF) “Garden of Michurintsev” in Novosibirsk. The research aims to study the efficiency of using the modern gene pool of grain and leguminous crops in different zones of Western Siberia. The authors found that West Siberian selection soybean varieties had higher growth and development rates than the Doka standard for 4-6 days. During studies with F1 hybrids of corn, the authors also note increased indicators of biometric parameters: plant height, green mass, and cob weight - by 20% of the Ross 140 F1 standard. High yield parameters of corn grain on the leached chernozem of the forest-steppe zone (EEF Praktik) of hybrids Ross 199 F1 - 10.2, KS-178 F1 and Krasnodar 194 F1 - 9.79 t/ha were revealed, exceeding the Ross 140 F1 standard by 40– 47%. Corn grains of hybrids F1 Ross 199 - 6.03 t/ha, Krasnodar 194 - 5.67 and KS-178 - 5.52 t/ha differed in yield with an excess of the standard by 54% on the southern chernozem of the steppe zone of Nadezhda LLC The maximum yield of corn grain is in the hybrid F1 Kuban 101 and Katerina - at 9 t/ha on the leached chernozem of CJSC Irmen stud farm. The maximum yield of soybean grain is 3.44 t/ha for SibNIIK-9 and Gorinskaya on leached chernozem, which is higher than the standard for Doka by 67 and 57%. SibNIIK-9, Omskaya 4, and Gorinskaya were distinguished on grey forest medium loamy soil. The variety of the Far Eastern selection Alena and the early ripening varieties of the RRIO collection (All-Russian Research Institute of Oilseeds, named after V. S. Pustovoit, Krasnodar): Barguzin, Lira, Sonata, and Puma, had a developed above-ground mass and low grain productivity. It was statistically determined that the genotype determined the yield of corn grain by 39%, conditions of the year - by 25%, and interaction of factors - by 20%. In experiments with soybean on leached and southern chernozem, the grain yield depended on the genotype by 42%, the conditions of the year - by 27% and the interaction of factors - by 16%, on grey forest medium loamy soil, respectively, 47; 30 and 22%.

Microbial Community Variations and Bioconversion Improvements during Soybean-Based Fermentation by Kefir Grains.

Soybeans possess unexpected flavors and are difficult to be absorbed by the gastrointestinal tract. Kefir grain fermentation provides diverse strains and bioactive compounds, which may enhance flavor and bioaccessibility. Third-generation sequencing was applied to analyze the microbial diversity in milk and soybean kefir grains in this study. In both types of kefir grains, the most common bacterial genus was Lactobacillus, and their fungal communities were dominated by Kazachstania. Lactobacillus kefiranofaciens was the most abundant species in kefir grains, while Lactobacillus kefiri showed a higher proportion in soybean kefir grains. In addition, the quantification of free amino acids and volatile flavor compounds in soybean solution and soybean kefir have shown the increased content of glutamic acid and a decreased amount of unpleasant beany flavor compounds, demonstrating that the nutritive value and sensory properties of soybean can be improved by kefir grain fermentation. Finally, the bioconversion of isoflavones during fermentation and in vitro digestion was evaluated, suggesting that fermentation is beneficial for aglycone formation and absorption. To conclude, kefir fermentation is proposed to change the microbial structure of kefir grains, promote the nutritional value of soybean-based fermented products, and provide possible solutions for the development of soybean products.

Особенности формирования урожая сои на территории Республики Башкортостан

Abstract. The purpose of the study is to establish the features of the formation of soybean grain harvest in the territory of the Republic of Bashkortostan. Methods. Analysis of statistical information on soybean cultivation and agro-climatic resources in the territory of the Republic of Bashkortostan, field experience and field observations. The heat supply of soybeans was estimated by the sum of active temperatures, moisture availability – by the amount of precipitation, relative humidity and hydrothermal coefficient (GTK) during the soybean vegetation period (June-August). The sum of active temperatures, the amount of precipitation and the hydrothermal coefficient in the years of the study were calculated using statistical data from the Federal State Statistics Service. The variability of the features was estimated by the coefficient of variation. The nature and degree of interconnection of the features was determined by correlation-regression analysis using the Excel computer program. Results. The features of the process of formation of soybean yield in the territory of the Republic of Bashkortostan have been established. Morphometric indicators of soybean plants SIBNIIK 315 on the territory of the Republic of Bashkortostan have a smaller value than the passport parameters of this variety. The main limiting growth and development of plants, soybean yield in the Republic of Bashkortostan are moisture (correlation coefficient 0.866) and heat (correlation coefficient 0.592). The fertility of the soil in most of the territory of the republic is high enough for the growth and development of plants and does not limit the formation of the soybean crop. It is established that the dependence of soybean yield on the amount of precipitation, the sum of active temperatures and SCC has the form of a single-vertex curve. On the territory of the Republic of Bashkortostan in heat-supplying years, it is possible to compensate for the lack of moisture for the formation of a soybean crop by watering crops. Irrigation allowed the formation of soybean yields in field experiments by 5–6.4 c/ha more than on bogar. Scientific novelty. The features of the formation of the soybean crop are revealed and the degree and nature of the dependence of the soybean grain yield on the amount of precipitation and the amount of active temperatures in the period “June – August” are established.

Co-Inoculation of Non-Symbiotic Bacteria Bacillus and Paraburkholderia Can Improve the Soybean Yield, Nutrient Uptake, and Soil Parameters.

Due to its nutritional value and oil, soybean (Glycine max L.) became an economic crop in India and worldwide. The current study investigated the effect of forest-associated plant growth-promoting rhizobacteria (PGPR) on soybean yield and grain nutrient content. Five potential bacteria were used in this study based on their PGPR traits. The pot assay result with two crops (soybean and chickpea) confirmed the growth promotion activity of the two strains (Bacillus subtilis MpS15 and Paraburkholderia sabiae NvS21). The result showed significant (p < 0.05) enhancement in plant length and biomass with the seed treatment with strains (MpS15 and NvS21) compared to the control. Later both biocompatible potential strains were used in field experiments as individuals and consortia. Seed treatment of consortia significantly improves the nodulation and photosynthetic content more than individual treatments and control. Compared to the control, the co-inoculation of MpS15 and NvS21 increased soybean grain, straw yield, and grain NPK contents. Interestingly, soil parameters (organic carbon, available NPK) showed a strong correlation (p < 0.05) with plant parameters and nutrient uptake. Overall, our study provides strong relationships between soil parameters, microbial inoculum as consortia, and soybean performance, and these strains may be utilized as bioinoculant in future.

Does straw returning affect the root rot disease of crops in soil? A systematic review and meta-analysis

Straw returning is a sustainable way that does not destroy soil ecology in agronomic management. Some studies have found that straw returning may aggravate or reduce soilborne diseases in the past few decades. Despite the increasing number of independent studies investigated the effect of straw returning on root rot of crops, the quantitative analysis regarding the relationship between straw returning and crop root rot is still undefined. In this study, keywords co-occurrence matrix was extracted from 2489 published studies (published from 2000 to 2022, the same below) on controlling soilborne diseases of crops. The methods used for soilborne diseases prevention have shifted from chemical to biological and agricultural control since 2010. As root rot is the soilborne disease with the largest weight in keyword co-occurrence according to statistics, we further collected 531 articles focusing on crop root rot. Notably, the 531 studies are mainly distributed in the United States, Canada, China and other countries in Europe and the south and southeast of Asia, and focus on the root rot of soybean, tomato, wheat and other important grain crops or economic crops. Based on the meta-analysis of 534 measurements in 47 previous studies, we explored how 10 management factors (soil pH/texture, type/size of straw, depth/rate/cumulative amount of application, days after application, beneficial/pathogenic microorganism inoculated before application and annual N-fertilizer input) during straw returning affect root rot onset worldwide. The results showed that straw size and microorganisms inoculated before straw returning are the key factors affecting the incidence of root rot. In combination with actual agricultural production, detailed advice applicable to traditional farming system on the optimization management of straw returning was given. This study emphasized the significance of straw pretreatment and farmland management to reduce soilborne diseases during straw returning.

Formation of grain yield and quality indicators of soybeans under the influence of fungicidal protection

Soybean diseases reduce the energy of seed germination, dilute crops, reduce the photosynthetic surface and productivity of cultivated plants, and worsen quality indicators. The purpose of the study was to determine the effect of fungicidal protection on the yield and quality of soybean grain. The following methods were used to achieve it: field, chemical (to determine the quality indicators of soybean grain), and statistical (to assess the reliability of data). The study was conducted in 2021-2022 in the conditions of TOV Savarske, Obukhiv district, Kyiv region. Soybean varieties Amadea and Aurelina and 10 variants of fungicidal protection were examined. It was identified that the increase in soybean grain yield when using fungicides is 0.41-0.72 t/ha, compared to the control. The highest yield in the experiment was obtained on the variants Celest top 312.5 FS, TH (1 l/t) + Abacus (2 l/ha) and Standak Top (2 l/t) + Abacus (2 l/ha) – 3.31 and 3.37 t/ha and 3.06 and 3.13 t/ha, respectively, in the varieties Amadea and Aurelina. There was no effect of the fungicides under study on the moisture content of soybean grains and the fat content of soybean seeds. There is an increase in protein content by 0.3-1.8% in variants with the use of fungicidal protection, compared to the control. The highest fat and protein content was obtained on the variant Standak Top (2 l/t) + Abacus (2 l/ha) and Celest top 312.5 FS, TH (1 l/t) + Abacus (2 l/ha) – 21.9 and 21.7% and 38.5 and 42.4%, respectively, in the varieties Amadea and Aurelina. The results of the conducted studies can be used in production conditions to improve the protection of soybean crops from diseases and increase the yield and quality of grain of this crop

Selenium Speciation in Se-Enriched Soybean Grains from Biofortified Plants Grown under Different Methods of Selenium Application

Since soybean is widely cultivated around the world and has a high protein content, it is a great nutritional vehicle for increasing the dietary uptake of selenium (Se). Several studies have evaluated biofortification with Se through fertilizer application in several crops. However, it is not clear how each method and source affect the total Se content or Se species in soybean grains. This work aimed to assess the total Se content and Se speciation in Se-enriched soybean grains produced under different Se application methods in the field. The treatments consisted of Se application (soil or foliar), using organic or inorganic Se sources at 10 g ha-1 or 80 g ha-1, in two genotypes. The results showed that all treatments with inorganic Se (soil and foliar) increased the Se content in grains compared with the control. More than 80% of the total Se in grains was present as selenomethionine (SeMet), and the speciation was affected by the Se source and the method of application. The treatments using inorganic Se, applied via soil or foliar, produced the highest content of Se as SeMet in soybean grains. Finally, we propose that the preservation of the Se species in products derived from soybean grains be evaluated as the following step.

Structural soil quality and system fertilization efficiency in integrated crop-livestock system

The nutrient use efficiency in integrated crop-livestock systems under system fertilization may be related to soil structural variations caused by grazing. These hypothetical cause-effect relationships are not known, which reflects a limited understanding of the underlying processes. This study evaluated the association between soil structural quality and system fertilization efficiency of phosphorus and potassium in an integrated crop-livestock system and a pure crop system. The treatments were two fertilization strategies (system fertilization and crop fertilization) in a factorial scheme with two production systems (an integrated crop-livestock system and a pure crop system) distributed in a randomized block design with four replicates. In the pure crop system, soybean was grown followed by Italian ryegrass as a non-grazed cover crop. In the integrated crop-livestock system, the ryegrass was grazed by sheep. In the crop fertilization strategy, phosphorus and potassium were applied at the soybean planting, and nitrogen in the ryegrass establishment. In the system fertilization strategy, nitrogen, phosphorus, and potassium were applied during the establishment of ryegrass. Soil physical quality indices were calculated for the beginning, middle, and end of the pasture phase (2020) and at the soybean harvest (2021). Forage and soybean production were also evaluated. Based on the soil physical quality index, the soil’s ability to perform its physical functions decreased from 94% under an integrated crop-livestock system to 89% under a pure crop system. The results indicated higher total forage production (36%) and soybean yield (13%) in the system fertilization strategy as compared to the crop fertilization strategy. Moreover, the integrated crop-livestock system produced more forage (31%) and soybean grains (15%) than the pure crop system. The study provides the first evidence that higher structural quality of soils in an integrated crop-livestock system favors crop yields at all stages of production. However, the nutrient use efficiency in system fertilization is only partially explained by the soil’s physical quality.

SOYBEAN BASE FERTILIZATION: CHEMICAL AND MICROBIOLOGICAL SOIL INDICATORS AND CROP YIELD

Recent research suggests that soybean yield could be doubled in Brazilian conditions, implying that the base fertilization is pivotal, as it might influence chemical and microbiological soil indicators and, hence, the crop grain yield. The current study had the goal of assessing alterations in the chemical and microbiological soil indicators, in the short term, as well as the soybean biometric and grain yield performance as a function of different fertilizers for base fertilization, in two sowing periods. An experiment comprised of two sowing periods was carried out in the 2019/2020 season on a dystrophic Red Latosol, in north Parana state. Five treatments were assessed, comprising: 1) control; 2) mineral fertilizer; 3) organomineral fertilizer; 4) mineral fertilizer mixed with granulated gypsum; and 5) slow release mineral fertilizer. A randomized block design with four replicates was adopted. The following variables were assessed: chemical and microbiological soil indicators; final stand; first pod insertion height; plant height; stem diameter; number of pods per plant; number of grains per plant; number of grains per pod; grain mass per plant; and one thousand grain mass and grain yield. There is no base fertilization effect on the chemical soil indicators in the short term, however, there is an effect on the microbiological soil indicators. Soybean biometric and grain yield performance is decreased with the delayed sowing period, regardless of the type of fertilizer utilized for base fertilization. Analyzing a set of soil quality indicators enables precise and judicious results to be gathered on management practices in the soil environment.