Location: Crop Production Systems Research
Project Number: 6066-22000-095-004-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Apr 1, 2024
End Date: Mar 31, 2025
Objective:
Evaluate micronutrients application on nutrient uptake, partitioning, yield, and soybean quality under irrigated and non-irrigated conditions in the Mississippi Delta.
Approach:
We will use a 10-acre field for this research in Baker farm (USDA-ARS facility) located at Stoneville, Mississippi. The soil will be Tunica clay with ~ 55% clay, 28% silt, and 17% sand. The experimental design will be a strip trial with four randomized fertilizer combinations, and one soybean hybrid replicated four times. Each plot will be 8 rows (1-8 rows passes) and 200 ft long. Within each replication, 32-rows (from one side) will be randomly irrigated, there will be 8 rows ally in between and the other 32-rows will be non-irrigated to assess the impact of micronutrients on both irrigated and non-irrigated field conditions on soybean yield and quality. Soil samples will be collected before planting and analyzed for N, P, K, Ca, Mg, S, Zn, Fe, pH, etc. Commercially grown soybean hybrid will be used for the study.
Nutrient uptake and remobilization will be determined by sampling plots at the V4 (fourth tri-foliate), V7 (seventh trifoliate), R2 (full bloom), R4 (full pod), R6 (full seed), and R8 (full maturity). Plant tissue samples (10 plants per plot) will be collected when ~50%of the plants exhibit the respective growth state. Each plant will be separated to stem (stems and petioles), leaf (individual leaves), reproductive (flowers and pods), and grain tissue components. Stem, leaf, and reproductive tissues will be dried at 70°C to a 0% moisture concentration for dry weight determination. Grain nutrient content at R6 will be determined from hand sample plants, and nutrient uptake at R8 and quality parameters (protein, oil content etc.) will be measured using combine-harvest grain. Stem, leaf, reproductive, and grain tissues will be ground to pass through a 2-mm mesh screen for nutrient concentration analysis. All samples will be analyzed for N, P, K, Ca, Mg, S, Zn, Mn, B, Fe, and Cu.
Canopy reflectance will be measured using spectroradiometer ASD Fieldspe4 that records light reflectance in the 350-2500 nm range to assess spatial and temporal variability due to micronutrient application during the growing season to predict soybean yield. Statistical and machine-learning approaches will be used to analyze collected data. The field will be harvested using a 2-row combined harvester and will collect yield from the middle four rows. Soybean seed sub-samples will be collected to assess quality parameters.
