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

Abstract

Twin-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), alternatefurrow 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. INTRODUCTIONMaize (Zea mays L.) is a major row crop in the state of Mississippi with ∼0.25 M ha planted in 2021, yielding about