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

Farmers are interested in more cost-efficient and environmentally sound fertilization programs in field crops. A multi-site study on the Canadian prairies was conducted to determine the effect 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. The 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 often 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.