This study aimed to investigate the influence of water availability and nitrogen fertilization on plant growth, nutrient dynamics, and variables related to soybean crop yield. Trials were performed in Teresina, Piauí, Brazil, using randomized blocks in a split-split plot arrangement. The plots corresponded to water regimes (full and deficient), the split plots to N fertilization (0 and 1000 kg ha⁻¹ N-urea), and the split-split plots to harvest times of soybean plants (16, 23, 30, 37, 44, 58, 65, 79 and 86 days after emergence), with three replicates. In general, the accumulation and partitioning of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulphur (S), copper (Cu), iron (Fe), manganese (Mn), zinc (Zn) and boron (B) were decreased in plants subjected to water deficit and without N fertilization. Although nitrogen fertilization promoted elevated N accumulation in tissues, it did not result in any significant yield gain, and the highest seed yields were found in plants under full irrigation, regardless of N supplementation. However, deficient irrigation decreased the seed oil content of N-fertilized plants. In conclusion, N fertilization is critical for nutrient homeostasis, and water availability impairs biomass and nutrient accumulation, thereby limiting soybean yield performance.

Soybean (Glycine max [L.] Merr.) seed yield is influenced by the seasonal availability of resources (i.e., nutrients, light, and water). While nitrogen (N) supply is becoming a soybean yield‐limiting factor, the N‐induced effect in seed yield components is still unclear. The objective of this research was to assess the effect of N supply on soybean yield components distribution within the canopy. A ‘Full‐N’ treatment, which provided the crop with ample N supply, was compared against a ‘Zero‐N’ treatment in which the crop relied on soil N and biological N fixation at nine high‐yielding irrigated soybean environments in Nebraska, with known levels of N limitation. Soybean seed yield components were determined at every node and grouped into five canopy sections. Seed yield ranged from 4378 to 7314 kg ha⁻¹ across environments and treatments. The greater N availability in the Full‐N increased yield by 984 kg ha⁻¹ in comparison to Zero‐N; via +253 seeds m⁻² (7%) and +16 mg seed⁻¹ (11%). N‐induced responses in seed yield occurred in the lower (nodes 0–4), middle (nodes 9–13), and middle‐upper sections (nodes 13–18). Seed number and pod number increased in the middle‐upper section. Notably, individual seed weight increased in all node sections. The seed number per pod response to N was negligible. The seed abortion within pods was 8%, but the Full‐N treatment reduced it by one percentage point. This study comprehensively examined the effects of N availability on soybean yield components within the canopy during their sequential establishment.

Rising production costs and declining commodity prices have compelled farmers to reassess their input and management strategies. Soybean [ Glycine max (L.) Merr] seed costs, in particular, have continued to increase due to advances in biotechnology, higher‐yielding germplasm, and available seed treatments, accounting for 32–35% of the total operational expenses in current soybean production systems. Optimizing seeding rate is therefore one area of consideration for improving profitability and maximizing return on investment. However, soybean yield response to plant population density is influenced by the combination of several factors, including water availability, temperature, radiation interception, planting practices, and crop growth and development. Unlike many other crops, soybean exhibits high phenotypic plasticity, allowing plants to adjust their growth and yield components (e.g., number of pods and seeds per plant) in response to varying plant population densities. As a result, the literature has shown that soybean can produce comparable yields across a wide range of plant population densities. The objectives of this management guide were to (i) provide an overview of factors influencing soybean yield response to seeding rate and plant population density and (ii) summarize recommendations by land grant university Extension agronomists across soybean‐producing states in the United States.

Harvest aids, such as foliar‐applied crop defoliants or desiccants, are tools available to soybean [ Glycine max (L.) Merr.] farmers that can homogenize maturity and help facilitate earlier soybean harvest, particularly when extreme weather events are forecasted. Prior research has shown soybean harvest aids increase harvest efficiency but has been limited primarily to states in the southern United States. Further investigation on the utility of harvest aids across the majority of US soybean production is warranted as incorrect desiccation timing can significantly reduce seed, protein, and oil yield. In 2024, a study was conducted at 19 sites across 13 US states to test the effect of planting date, maturity group, and desiccation timing on soybean seed yield, protein and oil yield, green stem incidence, and harvest timing. Seed yield reductions were rare when desiccation occurred at R7 but were common at R6.5 applications. Seed protein and oil yield was not affected by desiccation at R7 but was reduced with some R6.5 applications. Desiccation at R6.5 and R7 reduced green stem incidence 50% of the time. Harvest could occur 15 days earlier in the southern United States when desiccation occurred at R6.5 or R7, while harvest could occur 4 and 3 days earlier in the northern United States, respectively. Overall, the data show a harvest aid applied at soybean R7 can allow farmers to harvest earlier with low risk of seed, protein, or oil yield reductions.

Soybean [ Glycine max (L.) Merr.] seeding rate is typically set uniformly across entire fields, overlooking within‐field variability. On‐farm experimentation (OFE), combined with precision agriculture (PA) tools, can help determine optimal seeding rates across different areas of a field, generating data that support variable seeding rate decisions. Soil characteristics are factors that can help understand spatial variability in soybean yield and profit, assisting in identifying fields where variable rate seeding is suitable. This study aimed to (i) determine the economically optimal seeding rates per field and per soil type using OFE and (ii) benchmark current farmer seeding rates against the economically optimal seeding rates per field and across soil types. Eleven on‐farm soybean seeding rate trials were conducted in Nebraska, using variable‐rate prescriptions and randomized block designs. Yield data were cleaned and analyzed using mixed models with lme4 package in R to determine the economically optimum seeding rate (EOSR) by field and soil type level and to evaluate seeding rate effects on partial profit. The EOSRs across fields varied from 175,000 to 350,000 ha ⁻¹ and could be reduced in nine out of 11 fields without impacting yield and partial profit. Similarly, EOSRs for soil types ranged from 175,000 to 351,000 seeds ha ⁻¹ , with significant variation among soil types. This study expands the understanding of within‐field variability in soybean seeding rates based on soil characteristics and highlights the opportunity to reduce seeding costs to optimize partial profit in farmers’ fields.