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ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Water Management and Systems Research » Research » Publications at this Location » Publication #316761
Title: Argonomic practices of dryland grain sorghum maturity, yield, and test weight.

Author
item SAUER, SALLY - Colorad0 State University
item JOHNSON, JERRY - Colorad0 State University
item McMaster, Gregory
item Vigil, Merle

Submitted to: Extension Publications
Publication Type: Popular Publication
Publication Acceptance Date: 1/3/2015
Publication Date: 1/20/2015
Citation: Sauer, S.M., Johnson, J.J., McMaster, G.S., Vigil, M.F. 2015. Argonomic practices of dryland grain sorghum maturity, yield, and test weight.. Extension Publications. 3(1):9-11.

Interpretive Summary: INTERPRETIVE SUMMARY Grain sorghum [Sorghum bicolor (L.) Moench], or milo, is drought tolerant, is easy to incorporate into winter wheat crop rotations, has a low cost of production compared to corn, and the late date of planting provides flexibility in early-season weed control. Grain sorghum is an important crop in southeastern Colorado, but it has been produced on few acres in northeastern Colorado due the shorter growing season. The shorter season means a spring crop such as sorghum may not reach maturity before the first frost in the fall, which means significantly reduced yield and test weight. Grain sorghum production in northeastern Colorado has increased during the past few years due to a larger selection of short-season hybrids becoming available. This study examined whether sorghum production could be expanded into northeast Colorado. A 2-year study at Akron (2010, 2011), Fort Collins (2011), and Stratton (2010) investigated row orientation, seeding rate, and row spacing effects for three hybrids within early to medium-early maturity classes on the time to physiological maturity and grain yield. All treatments reached physiological maturity in the four trial environments. Hybrid selection and seeding rate significantly impacted the thermal time to reach physiological maturity. Row orientation and row spacing did not influence maturity. Yields were generally acceptable across all environments, hybrids, and agronomic treatments. Probabilities of the hybrids reaching maturity were high at Akron and Stratton (at least 62% and 86%, respectively, for the latest simulated planting date), but low for Fort Collins (highest of 75% for the earliest simulated planting date). Grain sorghum can successfully be grown in northeast Colorado, especially if planting early maturity hybrids using 0.76 m row spacing at a seeding rate close to 11 seeds m-2.

Technical Abstract: Grain sorghum [Sorghum bicolor (L.) Moench], or milo, is drought tolerant, is easy to incorporate into winter wheat crop rotations, has a low cost of production compared to corn, and the late date of planting provides flexibility in early-season weed control. Grain sorghum is an important crop in southeastern Colorado, but it has been produced on few acres in northeastern Colorado due the shorter growing season. The shorter season means a spring crop such as sorghum may not reach maturity before the first frost in the fall, which means significantly reduced yield and test weight. Grain sorghum production in northeastern Colorado has increased during the past few years due to a larger selection of short-season hybrids becoming available. This study examined whether sorghum production could be expanded into northeast Colorado. A 2-year study at Akron (2010, 2011), Fort Collins (2011), and Stratton (2010) investigated row orientation, seeding rate, and row spacing effects for three hybrids within early to medium-early maturity classes on the time to physiological maturity and grain yield. All treatments reached physiological maturity in the four trial environments. Hybrid selection and seeding rate significantly impacted the thermal time to reach physiological maturity. The medium-early hybrid (5745) matured significantly later than the early maturity hybrids (88P68 and DKS29-28). The seeding rate of 20 seeds m-2 matured significantly earlier than 11 seeds m-2, which matured much earlier than 3 seeds m-2. Row orientation and row spacing did not influence maturity. Yields were generally acceptable across all environments, hybrids, and agronomic treatments, and average yields among environments ranged from 1690 kg ha-1 to 4845 kg ha-1. Probabilities of the hybrids reaching maturity were high at Akron and Stratton (at least 62% and 86%, respectively, for the latest simulated planting date), but low for Fort Collins (highest of 75% for the earliest simulated planting date). Grain sorghum can successfully be grown in northeast Colorado, especially if planting early maturity hybrids using 0.76 m row spacing at a seeding rate close to 11 seeds m-2.