Barley Productivity Response to Polymer‐Coated Urea in a No‐Till Production System

Abstract

Farmers are interested in more cost-effi cient and environmentally sound fertilization programs in fi eld crops. A multi-site study on the Canadian prairies was conducted to determine the eff ect of polymer-coated urea (Environmentally Smart Nitrogen, ESN) compared with urea on weed management and barley (Hordeum vulgare L.) yield and quality. Treatments included a semi-dwarf and tall barley cultivar, polymer-coated urea (ESN) and urea, 100 and 150% of soil test N fertilizer rates, and 50 and 100% of registered herbicide rates. Treatments were applied to the same plots in four consecutive years. Barley yield was greater with semi-dwarf compared with tall barley in 13 of 20 site-years but weed biomass was greater in 7 of 18 site-years with the semi-dwarf cultivar. Th e 150% N fertilizer rate increased yield of both cultivars in 9 of 20 site-years and of the semi-dwarf cultivar in four additional site-years. Barley yield was oft en similar with ESN and urea but ESN increased barley yield in three site-years at both N rates, two additional site-years at the 150% N rate, and one further site-year with semi-dwarf barley. Barley grain protein concentration was greater with ESN than with urea in 8 of 20 site-years. Information gained in this study will be used to advise growers on improved barley production practices.

An economic study of controlled release urea and split applications of nitrogen as compared with non-coated urea under conventional and reduced tillage management

“…The blended application produced yield and NR similar to those of SCRU or split applications of urea in other locations. The results are consistent with the results of Blackshaw et al (2011) where barley seed yield under ESN was not significantly different than with urea for most site-years. Barley NR showed a linear increase to N application in almost all sites, with a quadratic component only at Melfort andLacombe under RT in 2004.…”

“…Malhi et al (2010) also noted that the higher cost of CRU must be considered when choosing a fertilizer, since the agronomic benefit was not consistent. Blackshaw et al (2011) completed another study on the Canadian prairies that compared the impacts of ESN fertilizer and urea at different application rates on barley yield and quality. The study found that ESN improved yield at 3 of 20 site-years but yield was not significantly different from that of urea at 15 of the 20 site-years.…”

“…The intent is to reduce the risk of N losses, thus improving N use efficiency and reducing potential negative environmental damage. Several studies have examined the environmental and agronomic impacts of using CRU with varied results (Nelson et al 2008Beres et al 2010;Cahill et al 2010;Hyatt et al 2010;Malhi et al 2010;Mckenzie et al 2010;Blackshaw et al 2011;Ziadi et al 2011;Yang et al 2011).…”

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

“…Nitrate leaching is a greater risk when these N sources are applied in the fall. Several studies have evaluated response to enhanced-efficiency N fertilizer in wheat [13][14][15][16], canola (Brassica napus L.) [17,18], and barley (Hordeum vulgare L.) [19]. Wheat yield response varied based on management, application timing, application rate, and environmental conditions.…”

“…Wheat yield response varied based on management, application timing, application rate, and environmental conditions. Studies of small grains show that, in addition to yield impacts, protein concentration with PCU was similar or increased compared to urea [15,19]. It is critical to understand the possible utility of enhanced efficiency fertilizer sources in order to properly integrate this technology into Midwestern wheat production systems.…”