Improving Maize Yield and Nutrient Use Efficiency with Plant Health Products.

While fertilizer application is an essential component of modern agriculture, excess fertilization can lead to increased grower costs and environmental degradation. Improving plant nutrient use efficiency (NUE) can maximize yield while minimizing fertilizer inputs. NUE can be divided into an uptake component (nutrient movement from the soil into plants) and a utilization component (nutrient transport within the plant to harvestable organs, e.g. grains). Regulation of internal plant nutrient levels is thought to occur both directly (e.g. nutrient based signals) and indirectly (e.g. hormones and other secondary signals). We are interested in utilizing the connections between plant nutrient status, plant hormone activity and yield components in order to improve NUE. To that end, a series of maize field trials were conducted in Texas, Illinois and Iowa over the 2012 and 2013 growing seasons to examine nitrogen and phosphorus NUE when applying plant health products at critical developmental stages. In most cases, the application of plant health products provided positive yield increases as well as increased kernel number, increased kernel nutrient concentration and increased nutrient use efficiency.