Nitrogen Management for Mid‐Atlantic Hard Red Winter Wheat Production

Abstract

Although soft red winter wheat (SRWW) (Triticum aestivum L.) is the predominant class in the Mid‐Atlantic, there is a recently established program for producers to grow hard red winter wheat (HRWW). This program offers a base price plus premiums for HRWW meeting quality (test weight and protein content) standards. This study's objectives were to evaluate the effect of N management strategies on HRWW yield and protein content and to determine the economic return using those strategies. Two HRWW cultivars used by producers in this HRWW program were produced at two locations in Maryland in a split plot arrangement of N treatments within a randomized complete block experimental design. Main plots (2002) were a factorial arrangement of those cultivars and four fall and Feekes growth stage (GS) 2/3 N treatments. Split plots (2002) were eight N timing and rate combinations at GS 5/6, GS 8, and/or GS 10.1. Main plots (2003) were a factorial arrangement of the cultivars and fall N supplied by either ammonium sulfate (AS) or urea‐ammonium nitrate (UAN) and GS 2/3 N treatments. Split plots (2003) were GS 5/6, GS 8, and 10.1 N timing and rate combinations. Wheat yield was significantly improved with GS 8 and/or 10.1 N applications both years. Protein content responded to GS 8 and 10.1 N applications in 2002; however, the response in 2003 was dependent on location and N amount at GS 5/6. Within the price and premium structure, best return was observed for split applications of N; 50 or 68 kg ha−1 at GS 2/3 followed at GS 5/6 with 50 or 68 kg N ha−1. No fall N benefit was observed.