132-7 Factors Influencing The Preplant Fertilizer Nitrogen Uptake Efficiency Of Furrow-Irrigated Corn.

See more from this Division: SSSA Division: Soil Fertility & Plant Nutrition
See more from this Session: Soil Fertility and Plant Nutrition Division and Nutrient Management and Soil and Plant Analysis Division Graduate Student Oral Competition - Nitrogen Managment (MS degree)

Monday, November 4, 2013: 2:45 PM
Tampa Convention Center, Room 15

Chester Greub1, Trenton L. Roberts2, Nathan A. Slaton2 and Richard J. Norman3, (1)Crop Soil and Environmental Sciences, University of Arkansas, Fayetteville, AR
(2)University of Arkansas, Fayetteville, AR
(3)Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR
Abstract:
Corn (Zea mays L.) is becoming an increasingly important row-crop in the Mid-south and irrigation is required to produce optimal yields. Nitrogen fertilizer is the largest line-item input cost for most producers and can represent as much as 28% of total operating costs. Current recommendations suggest that 1/3 of the N be applied preplant with the remainder applied prior to the V8 growth stage. Previous research indicates ~ 8% of the total plant N is taken up by the corn plant prior to the V6 growth stage. The objective of this research is to investigate the influence of preplant N rate and application strategy on Fertilizer N Uptake Efficiency (FNUE) in a furrow-irrigated corn production system. Preplant N rates ranged from 0 to100 kg N/ha and were applied using common application strategies including: preplant N incorporation, broadcast over the surface, and in-furrow application. All N fertilizer was applied immediately prior to planting using NBPT treated 15N-labeled urea. There was a significant two-way interaction involving preplant N rate by N application strategy (P=0.0009). Preplant FNUE for all treatments ranged from 1.6 to 13.3% with maximum FNUE being achieved when 67 kg N/ha was applied preplant N and incorporated into the bed. The broadcast N application displayed a linear increase in N uptake as N rate increased indicating that it was limited by N fertilizer placement. The in-furrow application strategy slightly increased in fertilizer N uptake as N rate increased, only reaching 1/3 the maximum amount of N taken up by the most efficient treatment, with a FNUE of only ~ 2.4%. Results of this research suggest that corn producers should incorporate their preplant N into the bed and only apply up to 67 kg N/ha in order to maximize preplant FNUE.

See more from this Division: SSSA Division: Soil Fertility & Plant Nutrition
See more from this Session: Soil Fertility and Plant Nutrition Division and Nutrient Management and Soil and Plant Analysis Division Graduate Student Oral Competition - Nitrogen Managment (MS degree)