Advanced Agronomic Practices to Maximize Feed Barley Yield, Quality, and Standability in Alberta, Canada. II. Responses to Supplemental Post‐Emergence Nitrogen. (1st July 2018)

• Record Type: Journal Article
• Authors: Perrott, L. A.; Strydhorst, S. M.; Hall, L. M.; Yang, R. C.; Pauly, D.; Gill, K. S.; Bowness, R.
• Is Part Of: Agronomy Journal. Volume 110:Number 4(2018)
• Page Start: 1458
• Page End: 1466
• Publication Date: 2018-07-01
• Subjects: Agronomy -- Periodicals; 630
• DOI: 10.2134/agronj2017.12.0684
• Languages: English
• ISSNs: 0002-1962

Abstract

Abstract : Agronomic solutions such as supplemental post‐emergence N may increase yield of feed‐barley grain. Grain yield, grain N yield, and grain protein generally increased as post‐emergence N rate increased. Largest grain yield increases occurred in environments with >300 mm of growing season precipitation. Yields decreased when N was applied as urea ammonium nitrate in hot and low‐precipitation conditions. There were no adverse negative effects to maturity, lodging, or grain quality in 'Amisk' feed barley. Small yield gains and decreasing feed barley ( Hordeum vulgare L.) acreage in Alberta may be addressed with agronomic solutions. Field experiments were conducted from 2014 to 2016 at 3 irrigated and 11 rain‐fed environments in Alberta, Canada, to determine the effects of supplemental post‐emergence N on 'Amisk' feed barley growth, grain yield, and grain quality. At the time of seeding, urea N was applied at rates suitable for targeting average yield potential in each environment. Just prior to BBCH 30 (beginning of stem elongation), this was supplemented with additional 0, 34, and 68 kg N ha −1 in the form of undiluted urea ammonium nitrate (UAN), and 34 kg N ha −1 with the urease inhibitor N‐(n‐butyl) thiophosphoric triamide (NBPT). In most environments, grain yield, grain N yield (grain yield × percentage grain N), and grain protein increased with post‐emergence N rate. The largest positive grain yield responses (up to 19%) usually occurred in environments with more than 300 mm of growing season precipitation. Grain yield and grain N yield were significantly reduced when post‐emergence N was applied in high temperatures with low precipitation. Post‐emergence N increased height, but did not markedly change lodging or days to maturity. The grain quality parameters of test weight, starch, and fiber had minor responses to post‐emergence N application. The addition of NBPT to post‐emergence N had little effect on any response variables. Supplemental post‐emergence N provided an agronomic solution for increasing feed barley grain yield, but consistent increases were limited to irrigated or high precipitation environments.