Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: N Placement, Row Spacing, and Irrigation Furrow Water Positioning Effects on Corn Yield

Authors
item Lehrsch, Gary
item Sojka, Robert
item Westermann, Dale

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 11, 2000
Publication Date: N/A

Interpretive Summary: Nitrogen, in water as the nitrate ion, can contaminate ground and surface water where present in quantity. Infants can become ill or die and pregnant women and the elderly infirm can suffer ill effects if they drink water with elevated nitrate concentrations. Furrow irrigation often leaches nitrate-nitrogen toward ground water, impairing its quality and reducing the efficiency with which fertilizer N is used by crops. This research seeks corn production systems to concurrently manage both furrow irrigation and applied N fertilizers to increase N use efficiency, maintain or increase yields, and protect water quality. For two years in southern Idaho, we evaluated the effects of N placement, row spacing, and irrigated-furrow positioning (applying water to the same or alternate side of the row with successive irrigations) on field corn yield and N uptake. Every second furrow was used to irrigate the corn nine times in 1988 and seven in 1989. Banding N below the soil surface on one side of a row, rather than applying the N fertilizer across the entire soil surface, and applying water season-long to the furrow on the other side of the row maintained or increased grain yield, increased silage yield by up to 26%, and increased N uptake in silage by up to 21%, particularly from N depleted soil. Placing N fertilizer into soil on a non-irrigated side of a row may increase N use efficiency, yields, and economic returns for producers who furrow-irrigate row crops.

Technical Abstract: Furrow irrigation often leaches Nitrate-N toward ground water. We hypothesized that banding and sidedressing N fertilizer on a nonirrigated side of a corn (Zea mays L.) row would maintain yield and decrease nitrate leaching. In a southern Idaho field of Portneuf silt loam (coarse silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid), we evaluated the effects of a) N placement (broadcast vs. banded), b) row spacing (0.76-m vs. a modified 0.56-m), and c) irrigated-furrow positioning (applying water to the same or alternate side of the row with successive irrigations) on field corn yield and N uptake. Every second furrow was used to irrigate the corn nine times in 1988 and seven in 1989. Compared to broadcasting, banding maintained grain yield in 1988 and increased it by 11% in 1989. Where N was banded in 0.56-m rows in 1989, silage yield where irrigating the same furrow was 22.9 Mg/ha, 22% greater (significant at P<0.001) than where irrigating alternating furrows. Compared to 0.56-m rows, 0.76-m rows had no effect on two-yr average grain yield but tended to increase two-yr average silage N. Banding N on one side of a row, rather than broadcasting, and applying water season-long to the furrow on the other side of the row maintained or increased grain yield, increased silage yield by up to 26%, and increased N uptake in silage by up to 21%, particularly from N depleted profiles. Applying water to the same, rather than alternating furrow reduced neither yield nor N uptake.

Last Modified: 8/22/2014
Footer Content Back to Top of Page