Timing Split Applications of Nitrogen for Irrigated Hard Red Spring Wheat

Abstract

Split N applications offer the potential for improving yield and quality of irrigated spring wheat (Triticum aestivum L.) while minimizing NO 3 − leaching losses. Field studies were conducted in 1985 and 1986 to evaluate the effects of N rate and timing on grain yield, test weight, and protein content of four hard red spring wheat varieties. The soil type was a Declo silt loam (coarse-loamy, mixed, mesic Xerollic Calciorthid). In both years, two N levels (60 and 120 Ib N/acre) were applied preplant, or as various combinations of preplant and topdressed N. Topdress applications of 30 Ib N/acre were made at either stem elongation (Feekes stage 7), anthesis (Feekes stage 10.5), or at both stem elongation and anthesis (...)