Nitrogen Fertilizer Sources and Application Timing Affects Wheat and Inter-Seeded Red Clover Yields on Claypan Soils

Agronomy

Kelly A. Nelson³  Peter P. Motavalli¹  Manjula Nathan²  Francesco Montemurro⁴ 

[1] Department of Soil, Environmental and Atmospheric Sciences, University of Missouri, Columbia, MO 65211, USA; E-Mail:;Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA; E-Mail:;Division of Plant Sciences, University of Missouri, Novelty, MO 63460, USA;id="af1-agronomy-04-00497">1Division of Plant Sciences, University of Missouri, Novelty, MO 63460, U

关键词: ammonium nitrate;    cover crop;    enhanced efficiency fertilizer;    nitrogen;    urea;    urease inhibitor;   

DOI  :  10.3390/agronomy4040497

来源: mdpi

【 摘 要 】

Controlled-release N fertilizer, such as polymer-coated urea (PCU), may be a fall N management option for wheat (Triticum aestivum L.) grown in poorly-drained claypan soils. Field research evaluated (1) urea release from fall-applied PCU in 2006 and 2007; (2) broadcast fall-spring split (25%:75%) of N sources; and (3) a single fall (100%) application of PCU, urea, urea plus NBPT (N-(n-butyl) thiophosphoric triamide] (U + NBPT), ammonium nitrate (AN), or urea ammonium nitrate (UAN) at 0, 56, 84, and 112 kg·N·ha⁻¹ on wheat yield, wheat biomass, N uptake by wheat, and frost-seeded red clover (FSC) (Trifolium pratense L.) forage yield (2004–2007). PCU applied in fall released less than 30% urea by February. Urea released from PCU by harvest was 60% and 85% in 2006 and 2007, respectively. In poorly-drained soils, wheat yields ranked PCU > AN > U + NBPT > urea ≥ UAN over the rates evaluated for fall-only application. PCU was a viable fall-applied N source, with yields similar to or greater than urea or U + NBPT split-applied. Split-N applications of AN, urea, UAN, and U + NBPT generally resulted in greater wheat yields than a fall application. Enhanced efficiency fertilizers provide farmers with flexible options for maintaining high yielding production systems.

【 授权许可】

CC BY   
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