Soybean [Glycine max (L.) Merr.] seed composition and yield are a function of genetics (G), environment (E), and management (M) practices, but contribution of each factor to seed composition and yield are not well understood. The goal of this synthesis-analysis was to identify the main effects of G, E, and M factors on seed composition (protein and oil concentration) and yield. The entire dataset (13,574 data points) consisted of 21 studies conducted across the United States (US) between 2002 and 2017 with varying treatments and all reporting seed yield and composition. Environment (E), defined as site-year, was the dominant factor accounting for more than 70% of the variation for both seed composition and yield. Of the crop management factors: (i) delayed planting date decreased oil concentration by 0.007 to 0.06% per delayed week (R2∼0.70) and a 0.01 to 0.04 Mg ha-1 decline in seed yield per week, mainly in northern latitudes (40–45 N); (ii) crop rotation (corn-soybean) resulted in an overall positive impact for both seed composition and yield (1.60 Mg ha-1 positive yield difference relative to continuous soybean); and (iii) other management practices such as no-till, seed treatment, foliar nutrient application, and fungicide showed mixed results. Fertilizer N application in lower quantities (10–50 kg N ha-1) increased both oil and protein concentration, but seed yield was improved with rates above 100 kg N ha-1. At southern latitudes (30–35 N), trends of reduction in oil and increases in protein concentrations with later maturity groups (MG, from 3 to 7) was found. Continuing coordinated research is critical to advance our understanding of G × E × M interactions.

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The understanding of source-sink dynamics during reproductive stages is essential to increase crop productivity and to describe yield component determination in eco-physiological models. Previous studies in soybean (Glycine max [L.] Merr.) evaluated the effect of changes in assimilate supply from the beginning of rapid seed growth but not at different times during the seed-filling phase or at the single-pod level. Two source-sink manipulation experiments were conducted in the greenhouse to quantify the effect of assimilate supply during the seed-filling phase on final seed weight of soybean. One pod on each node containing 3 mm seeds was marked in all plants, and pods not marked were removed at weekly intervals to avoid sink competition for assimilates. Removing pod competition on the day of marking and up to 21 days later increased final seed weight in marked pods by 25% relative to the control and by 18% when pod competition was removed 28 days after marking. Pods acquired mature color 33-35 days after marking. At 21 and 28 days after marking of individual pods, seeds had achieved 73% and 97% of their final seed weight and had 67 and 62% moisture, respectively. Our study provides new evidence that the final seed weight can still respond to increases in assimilate supply applied by the end of the seed-filling phase. These results highlight the potential to increase soybean yield through management practices and breeding efforts that extend the duration of a photosynthetically active canopy and increase assimilate supply to developing seeds during late seed-fill.

An evaluation of the physicochemical characteristics and colour in Murciano‐Granadina goat milk was carried out on several samples subjected to different pasteurization treatments (72°C/15 s, 76°C/15 s and 80°C/10 s). An apparent increase in the level of caseins was observed along with a decrease in the serum protein contents at pasteurization temperatures of 76 and 80°C. This change can be partly justified by the interactions between β‐lactoglobulin and K‐casein in pasteurized milk. The fat content, viscosity and density of the milk showed minimal sensitivity to the thermal treatments, but the heat treatment did affect the parameters which defined the colour of the milk, as shown by a decrease in the Yellow Index and an increase in the difference in colour.