About Us | Help Videos | Contact Us | Subscriptions
 

Members of ASA, CSSA, and SSSA: Due to system upgrades, your subscriptions in the digital library will be unavailable from May 15th to May 22nd. We apologize for any inconvenience this may cause, and thank you for your patience. If you have any questions, please call our membership department at 608-273-8080.

 

Institutional Subscribers: Institutional subscription access will not be interrupted for existing subscribers who have access via IP authentication, though new subscriptions or changes will not be available during the upgrade period. For questions, please email us at: queries@dl.sciencesocieties.org or call Danielle Lynch: 608-268-4976.

Abstract

 

This article in AJ

  1. Vol. 95 No. 4, p. 892-899
     
    Received: Mar 6, 2002


    * Corresponding author(s): dgungula@yahoo.com
 View
 Download
 Alerts
 Permissions
Request Permissions
 Share

doi:10.2134/agronj2003.8920

CERES-Maize Predictions of Maize Phenology under Nitrogen-Stressed Conditions in Nigeria

  1. D. T. Gungula *a,
  2. J. G. Klingb and
  3. A. O. Togunc
  1. a Dep. of Crop Prod., Federal Univ. of Technol., P.M.B. 2076, Yola, Adamawa State, Nigeria
    b Int. Inst. of Trop. Agric. (IITA), c/o L.W. Lambourn and Co., 26 Dingwall Rd., Croydon CR9 3EE, UK
    c Dep. of Crop Protection and Environ. Biol., Univ. of Ibadan, Ibadan, Nigeria

Abstract

Simulation models have the potential of greatly enhancing decision-making by farmers and researchers in Nigeria. These models however, need to be adapted before use. This study was conducted to test the phenology module of CERES-Maize model version 3.5 under varying N rates as a step toward adapting the model in the Southern Guinea Savanna of Nigeria. Data on seven late-maturing cultivars of maize (Zea mays L.) grown under 0, 30, 60, 90, and 120 kg N ha−1 in the field for two seasons were used for running the model. There was a linear relationship between N rates and days to silking and maturity with R 2 values of > 0.70 for most of the cultivars, indicating that N strongly influenced phenology. Predictions of days to silking at high N rates (90 and 120 kg N ha−1) were close, with most prediction errors of <2 d. The highest deviations in the calibration results were 4 and 2 d for 90 and 120 kg N ha−1, respectively, while in the validation results, they were 1 and 2 d. Similarly, days to maturity were closely predicted by the model at high N rates with <2-d deviations for most predictions. At low N rates, however, there were greater deviations in model predictions. This shows that the CERES-Maize model can be reliably used for predicting maize phenology only under nonlimiting N conditions. Thus, a N stress factor needs to be incorporated into the model for more accurate phenology prediction in low-N tropical soils.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2003. American Society of AgronomyPublished in Agron. J.95:892–899.