Dryland corn yield affected by row configuration and seeding rate in the Northern Great Plains

Authors: Allen, Brett

Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/17/2011
Publication Date: 1/1/2012
Citation: Allen, B.L. 2012. Dryland corn yield affected by row configuration and seeding rate in the Northern Great Plains. Journal of Soil and Water Conservation. 67(1): 32-41.

Interpretive Summary: Dryland corn production in the northern Great Plains (NGP) is limited by risk of crop failure due to drought conditions. Altering the row configuration and seeding rate have reduced the risk of yield loss elsewhere, but those areas typically receive greater precipitation than the annual average 300-350 mm of the NGP. A study in 2007 and 2008 determined the impact of seeding rate and row configuration on dryland corn yield, yield quality and components, and precipitation use efficiency (PUE). Four sites in north eastern Montana were planted to corn at four target rates (25,000, 37,500, 50,000 and 62,500 seeds ha-1) in conventional 0.61 m spaced rows or in a skip row configuration with every third row skipped. Altering the row configuration had no impact on grain yield, harvest index (HI), or grain PUE, but biomass yield and PUE were 12% and 15% greater for skip row than conventionally spaced corn. Interactions between row configuration and seeding rate were not significant (P<0.05). Compared to row configuration, seeding rate had a greater impact on yield and showed an inverse and linear relationship, where biomass, grain yield, HI, and PUE for grain and biomass were 19%, 229%, 200%, 222%, and 22% greater for the lowest than highest seeding rate, respectively. Overall results suggest that for areas with low rainfall, skip row spacing provides a modest increase in biomass yield, and that adjusting seeding rates to 25,000 seeds ha-1 or lower will likely increase dryland corn biomass and especially grain yield, reduce seed costs, and increase planting efficiency.

Technical Abstract: Dryland corn production in the Northern Great Plains (NGP) is limited by risk of crop failure due to drought conditions. Altering the row configuration and seeding rate have reduced the risk of yield loss elsewhere, but those areas typically receive greater precipitation than the annual average 300-350 mm of the NGP. A study in 2007 and 2008 determined the impact of seeding rate and row configuration on dryland corn yield, yield quality and components, and precipitation use efficiency (PUE). Four sites in north eastern Montana were planted to corn (same variety) at four target rates (25,000, 37,500, 50,000 and 62,500 seeds ha-1) in conventional 0.61 m spaced rows or in a skip row configuration with every third row skipped. Altering the row configuration had no impact on grain yield, harvest index (HI), or grain PUE, but biomass yield and PUE were 12% and 15% greater for skip row than conventionally spaced corn, respectively. Interactions between row configuration and seeding rate were not significant (P<0.05). Compared to row configuration, seeding rate had a greater impact on yield and showed an inverse and linear relationship, where biomass, grain yield, HI, and PUE for grain and biomass were 19%, 229%, 200%, 222%, and 22% greater for the lowest than highest seeding rate, respectively. Overall results suggest that for areas with low rainfall, skip row spacing provides a modest increase in biomass yield, and that adjusting seeding rates to 25,000 seeds ha-1 or lower will likely increase dryland corn biomass and especially grain yield. Abbreviations: CNV, conventional row spacing; HI, harvest index; NGP, Northern Great Plains; PUE, precipitation use efficiency; SKP, skip row spacing with every third row not planted.