Source: UNIVERSITY OF ARKANSAS submitted to
FERTILIZER REQUIREMENTS FOR CORN AND GRAIN SORGHUM
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0178662
Grant No.
(N/A)
Project No.
ARK01753
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2003
Project End Date
Dec 31, 2005
Grant Year
(N/A)
Project Director
Muir, J. H.
Recipient Organization
UNIVERSITY OF ARKANSAS
(N/A)
FAYETTEVILLE,AR 72703
Performing Department
CROP AND SOIL ENVIRONMENTAL SCIENCE
Non Technical Summary
Nitrogen management for corn involves providing adequate N throughout the growing season while minimizing loss of N under conditions of excess water. This research should provide information on how to most efficiently supply N throughout the growing season under Arkansas conditions. The aim is to determine whether a starter N fertilizer and/or late application of N, in addition to the recommended quantity, are economically beneficial for corn production in Arkansas.
Animal Health Component
60%
Research Effort Categories
Basic
40%
Applied
60%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1021510101090%
1021520101010%
Goals / Objectives
1. To evaluate a) nitrogen as a starter fertilizer, b) several ratios of preplant:sidedress nitrogen applications, and c) application of nitrogen at tasselling in a single experiment to determine their individual effects and to determine whether there are any interactions among them. 2. To identify situations under which deficiencies of nutrients occur in corn and grain sorghum and determine proper methods of alleviation.
Project Methods
Nitrogen management studies will be established on silt loam and silty clay soils. Fertility trials will be conducted on sites exhibiting nutrient deficiencies.

Progress 10/01/03 to 12/31/05

Outputs
In recent years, little data had been available on nitrogen management for the entire growing season for corn in Arkansas. While starter fertilizer and late season nitrogen applications had been shown to be of benefit in corn production, no studies had looked at all aspects of nitrogen fertilizer management together. Field experiments were established to evaluate starter fertilizers, several preplant/side-dress applied nitrogen combinations, and nitrogen applied at tasseling to determine their individual effects and to determine whether there are any interactions among them. Our earlier studies indicated significant responses to starter N and P alone in trials involving both starter fertilizer and in-furrow insecticides. Data from a three-year study indicated that starter fertilizer for corn increases yield and may be a worthwhile practice. In 2005, UA scientists enhanced our approach to take into consideration the amount and availability of native soil N to address the concern for the potential of over-application of N. Eight replicated field experiments were conducted at multiple locations on soils representing major corn producing counties of Arkansas. At all sites, 20 lb N/acre as ammonium sulfate was applied prior to or at planting and the remaining N balance was sidedressed as urea by hand when corn plants were at 8-10 leaf stage. Soil samples were collected before planting and before sidedress application. Analysis of variance (ANOVA) was performed to evaluate the effect of sidedress N application on corn yield for each site separately. There was a significant response to sidedress application N at all sites except one. Also, we did not observe any response to N application when soil Nitrate at 12-inch-depth was 79 lb/acre. In general, the maximum grain yield was obtained with N application of 200-250 lb/acre. At these rates, corn grain yield was almost twice the yield of the check (non-fertilized) plots. This research will continue and future findings will be reported under CRIS ARK02035.

Impacts
Data from these studies will serve as a scientific database for correlating and calibrating new soil tests for N recommendation for corn production in Arkansas.

Publications

  • No publications reported this period


Progress 01/01/04 to 12/30/04

Outputs
A study was conducted on a Calhoun silt loam soil at the Pine Tree Experiment Station (PTES) located near Colt, AR; on a Sharkey silty clay soil at the Northeast Research and Extension Center (NEREC) at Keiser, AR; on a Collins silt loam soil at the Arkansas State University farm (ASU) located in Jonesboro, AR; and on a Loring silt loam soil at the Cotton Branch Experiment Station (CBES) near Marianna, AR in 2004 to evaluate N as a starter fertilizer, several preplant/sidedress applied N combinations, and N applied at tasseling in a single experiment. Treatments included a) starter N at 0 and 13.4 kg N/ha, 5 cm below and 5 cm to the side of the seed at planting, b) four preplant/sidedress ratios (25/75, 33/67, 50/50, and 75/25), and c) 0 and 44.5 kg N/ha at tasseling. A factorial arrangement of treatments, 2 x 4 x 2 (starter N x preplant/sidedress ratio x tassel N rate) in a randomized complete block design with four replications was used. The N source for starter N treatments was urea ammonium nitrate (UAN) 32-0-0 at all four locations. Ammonium nitrate (33.5-0-0) was the preplant N source at all locations. The N source for the sidedress treatments and N at tasseling was urea. The sidedress N was applied between the rows by hand and mechanically incorporated at all locations. Plots were hand harvested at ASU. Plot combines were used to harvest plots at NEREC, PTES, and CBES). Yields were adjusted to 15.5% moisture for statistical analysis. When compared with the yields of the unfertilized control, corn receiving N fertilizer produced greater yields at all sites. However, N-fertilizer treatments had no significant influence on corn yields at the ASU, NEREC, and PTBS sites. At the CBES location, corn yields were significantly affected by starter N and a starter N x preplant/sidedress interaction, although data show no consistent trend for better or worse corn yields among treatments.

Impacts
The lack of significant differences among corn yields receiving N suggests that N fertilizer can be managed with a wide variety of methods for production of near maximum yields. Nearly optimal growing conditions during the 2004 growing season resulted in high yields at all locations when the recommended rate of N was applied.

Publications

  • Muir, J. H. and J. A. Hedge. 2004. Nitrogen fertilizer management for Corn. In Nathan A. Slaton (editor), Wayne E. Sabbe Arkansas Soil Fertility Studies 2003. University of Arkansas, Agr. Exp. Sta. Res. Ser. 515 pp. 50-52.


Progress 01/01/03 to 12/31/03

Outputs
A study was conducted on a Calhoun silt loam soil at the Pine Tree Experiment Station (PTES) located near Colt, AR; on a Sharkey silty clay soil at the Northeast Research and Extension Center (NEREC) at Keiser, AR; and on a Collins silt loam soil at the Arkansas State University farm (ASU) located in Jonesboro, AR in 2003 to evaluate N as a starter fertilizer, several preplant/sidedress applied N combinations, and N applied at tasseling in a single experiment. Treatments included a) starter N at 0 and 13.4 kg N/ha, 5 cm below and 5 cm to the side of the seed at planting, b) four preplant/sidedress ratios (25/75, 33/67, 50/50, and 75/25), and c) 0 and 44.5 kg N/ha at tasseling. A factorial arrangement of treatments, 2 x 4 x 2 (starter N x preplant/sidedress ratio x tassel N rate) in a randomized complete block design with four replications was used. The N source for starter N treatments was urea ammonium nitrate (UAN) 32-0-0 at all three locations. Ammonium nitrate (33.5-0-0) was the preplant N source at all locations. The N source for the sidedress treatments and N at tasseling was urea. The sidedress N was applied between the rows by hand and mechanically incorporated at all locations. Plots were hand harvested at ASU. Plot combines were used to harvest plots at NEREC and at PTES. Yields were adjusted to 15.5% moisture for statistical analysis. Nitrogen supply appeared to be adequate under all treatments at all three locations. The ratio of N applied preplant to that applied sidedressed did not affect yields. Aditional N applied as a starter or at tasseling also had no effect on yields. Although significant interactions and nearly significant interactions were examined, no practical significance could be identified. Often times, the numerically highest yield occurred with no starter N and no N at tasseling. Nearly optimal growing conditions during the 2003 growing season resulted in high yields at all locations.

Impacts
Although no N treatment had an effect on corn grain yield in 2003, this was the first year in five that no response was obtained with starter fertilizer in our trials. Prior results had consistently shown significant yield responses to starter fertilizer on the order of 629 kg/ha or more. Further data is needed to fully evaluate ratios of preplant/sidedress nitrogen applications and nitrogen applications at tasseling.

Publications

  • Muir, J. H. and J. A. Hedge. 2003. Nitrogen fertilizer management for Corn. In Nathan A. Slaton (editor), Wayne E. Sabbe Arkansas Soil Fertility Studies 2002. University of Arkansas, Agr. Exp. Sta. Res. Ser. 502:63-64.


Progress 01/01/02 to 12/31/02

Outputs
A phosphorus (P) and potassium (K) calibration trial was conducted at one location to determine whether modern hybrids, more intensive management systems, and crop rotations not previously used may result in different phosphorus and potassium requirements than required in years past. Phosphorus and K fertilizer rates of 0, 0.5, 1.0, and 2.0 times the recommended rates (recommended rates were 79 kg/ha P2O5 and 101 kg/ha K2O) for the lowest soil test values were applied broadcast and incorporated before planting. Applied P had no significant influence on corn grain yield with a soil test P value of 49. Previous trials showed significant yield responses to applied P at soil test P values of 22-33 kg/ha P2O5 in 3 of 5 years. Yield was significantly increased with applied K on a soil with a soil test K value of 229 kg/ha. A yield response to applied K at soil test values above 225 had not been found in the previous five years. A study was initiated in 2002 to evaluate nitrogen (N) as a starter fertilizer, several preplant/side-dress applied N combinations, and N applied at tasseling in a single experiment. There was no significant response to the different preplant/sidedress applications, nor to N applied at tasseling, nor to any interactions among the variables. There was a significant response to N starter fertilizer rate. Starter fertilizer has produced a significant yield increase every year in four years of trials.

Impacts
Results in previous years indicated that corn frequently responds to applied P and K at soil test levels that currently result in P and K fertilizer recommendations. The results from the 2002 trial indicated similar results for K. Results to date do not show a response to applied P and/or K at soil test levels too high to warrant a recommendation under the current guidelines. Results from six years of P and K calibration trials indicate that current soil test guidelines are accurate in determining P and K fertilizer recommendations. Starter fertilizer continues to show promise in corn production. Results to date consistently show a significant yield response to starter fertilizer on the order of 629 kg/ha or more.

Publications

  • Muir, J. H. and J. A. Hedge. 2002. Corn response to phosphorus and potassium fertilization at different soil test levels. In Nathan A. Slaton (editor), Arkansas Soil Fertility Studies 2001. University of Arkansas, Agr. Exp. Sta. Res. Ser. 490. pp. 32-33.
  • Muir, J. H. and J. A. Hedge. 2002. Corn response to nitrogen and phosphorus as starter fertiliizer. In Nathan A. Slaton (editor), Arkansas Soil Fertility Studies 2001. University of Arkansas, Agr. Exp. Sta. Res. Ser. 490. pp. 30-31.


Progress 01/01/01 to 12/31/01

Outputs
Phosphorus and potassium calibration trials are being conducted at two locations to determine whether modern hybrids, more intensive management systems, and crop rotations not previously used may result in different phosphorus and potassium requirements than required in years past. Application of K increased corn grain yield on soils with low, medium low, and medium K soil test levels in each of the first four years of the study and at the low level in 2001. Trials were conducted on the use of starter fertilizer and in-furrow insecticides for corn. In-furrow insecticides had no effect on corn grain yields at a new location in 2001. Phosphorus starter fertilizer increased yields by 1375 kg/ha. Sites where nutrient deficiencies in corn and grain sorghum are identified by Cooperative Extension personnel, growers, etc., will be examined and soil and plant samples collected. Corrective amendments will be applied at several rates if the deficiencies are identified early enough. A number of grain sorghum fields in northeast Arkansas with areas with slow growing plants and sometimes death of plants have been observed in the past several years. No cause or causes have been identified to-date. Problem fields will be monitored when identified. Soil and plant samples will be collected from these fields. Additionally, soil samples will be collected in sufficient quantities for greenhouse studies to attempt to identify the cause of the problem.

Impacts
Results indicate that corn responds to applied phosphorus and potassium at soil test levels that currently result in recommendations to apply P and K. Response to applied P and K at higher soil P and K levels is being studied. Starter fertilizer appears to be a management practice that significantly increases corn grain yield.

Publications

  • Muir, J. H. and J. A. Hedge. 2001. Corn response to phosphorus and potassium fertilization at different soil test levels. In R. J. Norman and S. L. Chapman (editors), Arkansas Soil Fertility Studies 2001. University of Arkansas, Agr. Exp. Sta. Res. Ser. 480, pp. 49-51.
  • Muir, J. H. and J. A. Hedge. 2001. Corn response to nitrogen and phosphorus as starter fertilizer. In R. J. Norman and S. L. Chapman (editors), Arkansas Soil Fertility Studies 2001. University of Arkansas, Agr. Exp. Sta. Res. Ser. 480, pp. 52-53.


Progress 01/01/00 to 12/31/00

Outputs
Phosphorus and potassium calibration trials are being conducted at two locations to determine whether modern hybrids, more intensive management systems, and crop rotations not previously used may result in different phosphorus and potassium requirements than required in years past. Application of K increased corn grain yield on soils with low, medium low, and medium K soil test levels in each of the first four years of the study. Trials were conducted on the use of starter fertilizer and in-furrow insecticides for corn. In-furrow insecticides increased corn grain yields by as much as 1823 kg/ha. Phosphorus starter fertilizer increased yields by 2075 kg/ha. Sites where nutrient deficiencies in corn and grain sorghum are identified by Cooperative Extension personnel, growers, etc., will be examined and soil and plant samples collected. Corrective amendments will be applied at several rates if the deficiencies are identified early enough. A number of grain sorghum fields in northeast Arkansas with areas with slow growing plants and sometimes death of plants have been observed in the past several years. No cause or causes have been identified to-date. Problem fields will be monitored when identified. Soil and plant samples will be collected from these fields. Additionally, soil samples will be collected in sufficient quantities for greenhouse studies to attempt to identify the cause of the problem.

Impacts
Results indicate that corn responds to applied phosphorus and potassium at soil test levels that currently result in recommendations to apply P and K. Response to applied P and K at higher soil P and K levels is being studied. In-furrow insecticides and starter fertilizer appear to be management practices that significantly increase corn grain yield.

Publications

  • Muir, J. H. and J. A. Hedge. 2000. Corn response to phosphorus and potassium fertilization at different soil test levels. University of Arkansas, Agr. Exp. Sta. Res. Ser. 471, pp. 81-86.


Progress 01/01/99 to 12/31/99

Outputs
Phosphorus and potassium calibration trials are being conducted at two locations to determine whether modern hybrids, more intensive management systems, and crop rotations not previously used may result in different phosphorus and potassium requirements than required in years past. Application of K increased corn grain yield on soils with low, medium low, and medium K soil test levels in each of the first two years of the study. Trials were conducted on the use of starter fertilizer and in-furrow insecticides for corn. Initial trials showed yield increases with both in-furrow insecticides and starter fertilizer. A number of grain sorghum fields in northeast Arkansas with areas with slow growing plants and sometimes death of plants have been observed in the past several years. Two such fields were monitored during 1999. Soil and plant samples were collected and are being analyzed in an attempt to determine the cause of the problem. No cause or causes have been identified to-date. Problem fields will continue to be monitored when identified. Soil and plant samples will be collected from these fields. Additionally, soil samples will be collected in sufficient quantities for greenhouse studies to attempt to identify the cause of the problem. Field trials with possible corrective amendments will be conducted if the deficiencies are identified early enough.

Impacts
Results indicate that corn responds to applied phosphorus and potassium at soil test levels that currently result in recommendations to apply P and K. Soil P and K levels are being increased in test plots in order to determine whether corn will respond to applied P and K at soil test values too high to warrant a recommendation under current guidelines.

Publications

  • No publications reported this period


Progress 01/01/98 to 12/31/98

Outputs
Phosphorus and potassium calibration trials are being conducted at two locations to determine whether modern hybrids, more intensive management systems, and crop rotations not previously used may result in different phosphorus and potassium requirements than required in years past. Trials will be conducted on the use of starter fertilizer and in-furrow insecticides for corn. Sites where nutrient deficiencies in corn and grain sorghum are identified by Cooperative Extension personnel, growers, etc., will be examined and soil and plant samples collected. Corrective amendments will be applied at several rates if the deficiencies are identified early enough. A number of grain sorghum fields in northeast Arkansas with areas with slow growing plants and sometimes death of plants have been observed in the past several years. Two such fields were monitored during 1998. Soil and plant samples were collected and are being analyzed in an attempt to determine the cause of the problem. Problem fields will continue to be monitored when identified. Soil and plant samples will be collected from these fields. Additionally, soil samples will be collected in sufficient quantities for greenhouse studies to attempt to identify the cause of the problem.

Impacts
(N/A)

Publications

  • No publications reported this period