Peanut Response to Crop Rotation, Drip Tube Lateral Spacing, and Irrigation Rates with Deep Subsurface Drip Irrigation

ABSTRACT Long term crop yield with various crop rotations irrigated with subsurface drip irrigation (SSDI) is not known for US southeast. A SSDI system was installed in 1998 on Tifton loamy sand soil with five crop rotations, two drip tube lateral spacings, and three irrigation levels. Crop rotations ranged from continuous peanut (Arachis hypogaea L) to four years between peanut. Laterals were installed beneath each crop row (0.91-m) and alternate row middles (1.83-m). Crops were irrigated daily at 100, 75 and 50% of estimated crop water use. Laterals spaced at 1.83 m had the same yield as laterals spaced at 0.91-m in nine out of ten years. The 50, 75, and 100% irrigation treatments averaged 3263, 3468, and 3497 kg/ha, respectively. There was no yield difference between the 75 and 100% irrigation treatments implying 25% water savings. Crop rotation affected peanut yield seven out of eight years and continuous peanut had lowest yield across all years. As time between peanut crops increased peanut yield inc...