Agronomic performance of soybean with varied planting dates, row configurations, and seeding rates on two different soil textures

Planting date, row configuration, and seeding rate are three critical factors in obtaining maximum soybean [Glycine max (L.) Merr.] grain yield and can vary based on soil texture. Therefore, two studies were conducted at the Delta Research and Extension Center in Stoneville, MS. The first study was conducted from 2019 to 2021 and sought to determine the effects of planting date (optimal and delayed 21 days), and row configuration (single-, twin-, and triple-row) on soybean growth, development, and grain yield. The second study was conducted in 2021 with three site-years to determine the effects of seeding rate (130,000, 180,000, and 220,000 seeds acre⁻¹) in a triple-row configuration on soybean grain yield compared to a single-row configuration at 130,000 seeds acre⁻¹ on two soil textures (silt loam and clay). Both studies were repeated on silt loam and clay soil textures in every site-year. In the first study, the optimal planting date increased soybean grain yield regardless of soil texture. On both soil textures, twin- and single-row configuration yields were equivalent, but triple-row configuration reduced soybean grain yield up to 9%. Similarly, triple-row configuration reduced soybean density and height at R3 and R8 growth stages. In the second study, increasing triple-row configuration soybean seeding rate by at least 38% provided similar soybean grain yields to a single-row configuration at 130,000 seeds acre⁻¹. These data indicate that triple-row soybean planting configurations do have some benefits, but that future research should focus on equipment limitations experienced in the current research.