Corn Growth and Nitrogen Uptake with Furrow Irrigation and Fertilizer Bands
1997
Benjamin, Joseph G. | Porter, Lynn K. | Duke, Harold R. | Ahuja, L. (Lajpat)
Furrow irrigation is commonly used to provide supplemental water to row crops. Alternate-furrow irrigation has been proposed as a method to decrease deep percolation water losses as well as the leaching of fertilizer and pesticides. A study was conducted on a Ulm clay loam (fine, smectitic, mesic Ustic Haplargids) in 1994 and 1995 near Fort Collins, CO. Corn (Zea mays L.) growth and N uptake were measured under alternate-furrow and every-furrow irrigation water applications, each with fertilizer bands placed either in the row or in the furrow. Nitrogen-15-depleted (NH₄)₂SO₄ fertilizer was used to distinguish plant uptake of fertilizer N from uptake of naturally occurring N. There were no differences in plant response to alternate-furrow or every-furrow irrigation water placement for the same amount of water applied. Greater fertilizer-N uptake occurred with row placement than with furrow placement of N fertilizer. Early in the growing season, fertilizer-N uptake from row placement was from 2 to 10 times the fertilizer-N uptake from furrow placement. By the end of the growing season, the average total-N uptake from row placement was 12% greater than for furrow placement. Placing the fertilizer in the nonirrigated furrow of the alternate-furrow irrigation treatment decreased N availability by 20% compared with the average of the other treatments. If alternate-furrow irrigation is used to increase water use efficiency in furrow-irrigated fields, placing the N fertilizer in the nonirrigated furrow of the alternate-furrow irrigation system could decrease N availability because of drier soil conditions in the nonirrigated furrow. Row placement of N fertilizer seems to be beneficial in both alternate-furrow and every-furrow irrigation applications. Supported in part by NRI Competitive Grants Program/USDA Grant no. 94-37102-1146.
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