Location: Crop Production Systems Research
Project Number: 6066-22000-089-010-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Apr 1, 2023
End Date: Mar 31, 2024
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 (divided into eight strips) 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. Each strip will be 16 rows (2-8 rows passes; ~0.60 acres). The strip will be divided into two sections. Within each strip, only 8-rows (from one side) will be randomly irrigated, and the other 8-rows will be non-irrigated to assess the impact of micronutrients on both irrigated and non-irrigated field conditions micro-nutrient application on soybean yield and quality. The yield will be collected from the middle four rows. The experimental design will be a strip trial with four randomized fertilizer combinations, and one soybean hybrid replicated. Phosphorus (P) and potassium (K) will be applied as recommended after soil testing. The fertilizer treatments will be (i) Control, (ii) Zn, (iii) Fe (iv) Zn + Fe. The Zn and Fe will be applied @ 10 lbs., and 5 lbs. ac-1, respectively. Soil samples will be collected before planting and analyzed for N, P, K, Ca, Mg, S, Zn, Fe, pH, etc. Commercially grown soybean hybrid in the Mississippi Delta region 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. We will collect UAS and satellite-based multi-spectral crop reflectance to assess spatial and temporal variability 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 combined harvester equipped with a yield monitor system. Soybean samples will be collected to assess quality. An economic analysis will be conducted to compare the profitability of the production system with the control treatments.
