Site-specific Relationship between Corn Population and Yield

Abstract. Although many studies have been conducted to determine plant population effects on corn yield, advances in breeding, equipment, and precision agriculture demonstrate that the need still exists to better understand the relationship. A field study was conducted at the University of Missouri Fisher Delta Research Center Marsh Farm at Portageville during the 2013 and 2014 growing seasons to investigate factors affecting Mid-South corn production. The overall objective was to improve site-specific management of Mid-South corn and this report deals with the relationship between final plant population and yield for a subset of the study consisting of one hybrid planted at four densities ranging from 74,000 to 104,000 seeds per hectare. Mechanical population sensors were used to count the stalks at harvest. Spatial regression analyses were used to investigate the relationship between the target seeding rate and the final stalk counts. Although no significant relationship was observed in 2013, a better relationship was observed in 2014. A stronger relationship was observed between the final stalk counts and yield than between target seeding rate and stalk counts in both 2013 and 2014. The next step will include repeating the analyses on additional treatments in this study as well as other fields and under different environments to increase understanding of the impact of crop inputs, weather, and soil variability and use that information to improve site specific application of inputs.