Advanced Agronomic Practices to Maximize Feed Barley Yield, Quality, and Standability in Alberta, Canada. I. Responses to Plant Density, a Plant Growth Regulator, and Foliar Fungicides

Barley (Hordeum vulgare L.) yield has increased at a slower rate than other major crops in Alberta, and barley area has declined over the last two decades. Improved agronomic management may increase grain yield and address other production constraints such as lodging, disease, and quality limitations. Field experiments were conducted in 2014, 2015, and 2016 at four rainfed sites and one irrigated site in Alberta, Canada, to evaluate the effects of plant density (targeting 240 or 355 plants m(-2)), the plant growth regulator chlormequat chloride (CCC; 2-chloroethyl-trimethyl-ammonium chloride), foliar fungicide application (at flag leaf, 2 wk later, or at both application [dual] timings), four rates of post-emergence N, and the interaction of these factors on 'Amisk' feed barley. There was no post-emergence N interaction with the other agronomic practices tested in this study. The CCC did not markedly reduce height or lodging, but increased grain yield by 2%. Test weight increased by 0.5 kg hL(-1) with CCC at 240 plants m(-2). Foliar fungicides resulted in an average yield increase of 3% in the low disease conditions encountered in the study. Dual fungicide applications increased yield over single applications at the 355 plants m(-2) density only. Combined, the most intensive agronomic practices (355 plants m(-2), CCC, and dual fungicide applications) provided a 7% grain yield increase compared to the low intensity control.