Effect of irrigation regimes and planting patterns on maize production in humid climates

Abstract

AbstractTwin‐row planting in maize (Zea mays L.) has potential for reducing plant‐crowding stress for optimizing grain yield and resource use. A study was conducted in 2020 and 2021 on a Dundee silt loam in the Lower Mississippi Delta (LMD) region of the United States to evaluate maize grain yield and irrigation water use efficiency (IWUE) in single‐row (SR) and twin‐row (TR) planting patterns with same seed rate under four irrigation regimes: rainfed (RF), all‐furrow irrigation (FI), alternate‐furrow irrigation (AFI), and every third‐furrow irrigation (TFI). The TR enhanced grain yield by 9.2% in 2020 and 10.9% in 2021 over the SR system. The average final plant density at the reproductive phase was highest under AFI (73,900 ha−1) and lowest under RF (70,480 ha−1). Across all irrigation regimes, the leaf area index was significantly higher in the TR system. Average grain yields under SR were 10.01, 10.44, 9.48 and 9.10 Mg ha−1, respectively, in FI, AFI, TFI and RF; average grain yields under TR were 11.58, 11.32, 10.13 and 9.91 Mg ha−1. The AFI and FI recorded similar grain yields. The IWUE was highest in TR planting (0.028 kg m−3), followed by SR planting (0.024 kg m−3) under AFI. The IWUE of TFI in TR planting was 0.020 kg m−3 and in SR was 0.011 kg m−3. Economic analysis revealed that the TR‐FI and TR‐AFI had average profits of 446 and 432 US$ ha−1, respectively. The study suggests that maize producers in the LMD can save a significant amount of irrigation water without compromising grain yields by adapting the AFI‐TR system.