Estimating maize nutrient uptake requirements
Generic, robust models are needed for estimating crop nutrient uptake requirements. We quantified and modeled grain yield–nutrient uptake relations in maize grown without significant biotic and abiotic stresses. Grain yield and plant nutrient accumulation in above-ground plant dry matter (DM) of com...
Saved in:
Published in | Field crops research Vol. 118; no. 2; pp. 158 - 168 |
---|---|
Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
Elsevier B.V
08.08.2010
[Amsterdam]: Elsevier |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Generic, robust models are needed for estimating crop nutrient uptake requirements. We quantified and modeled grain yield–nutrient uptake relations in maize grown without significant biotic and abiotic stresses. Grain yield and plant nutrient accumulation in above-ground plant dry matter (DM) of commercial maize hybrids were measured at physiological maturity in on-station and on-farm experiments in Nebraska (USA), Indonesia, and Vietnam during 1997–2006. These data were used to model the nutrient requirements for yields up to 20
Mg
ha
−1 using the QUEFTS (QUantitative Evaluation of the Fertility of Tropical Soils) approach. The model required estimation of two boundary lines describing the minimum and maximum internal nutrient efficiencies of N, P and K (IE, kg grain per kg nutrient in plant DM), which were estimated at 40 and 83
kg grain
kg
−1 N, 225 and 726
kg grain
kg
−1 P and 29 and 125
kg grain
kg
−1 K, respectively. The model predicted a linear increase in grain yield if nutrients are taken up in balanced amounts of 16.4
kg N, 2.3
kg P and 15.9
kg K per 1000
kg of grain until yield reached about 60–70% of the yield potential. The corresponding IEs were 61
kg grain
kg
−1 N, 427
kg grain
kg
−1 P and 63
kg grain
kg
−1 K. The model predicted a decrease in IEs when yield targets approached the yield potential limit. A spherical model was derived from QUEFTS model outputs and found to be particularly suitable for practical applications such as estimating fertilizer needs. The proposed spherical model offers generality across environments and management practices, allowing users to estimate the optimal N, P and K uptake requirements based on two inputs: estimated yield potential and yield target. Further improvements in modeling the relationship between N uptake and grain yield can be made by taking into account differences in harvest index. Accuracy in the simulation of N uptake using the spherical model was improved from an RMSE of 35
kg N
ha
−1 to 25
kg N
ha
−1 when harvest index was accounted for, suggesting that the relationship between N uptake and actual yield is affected by both yield potential and efficiency in biomass partitioning. |
---|---|
Bibliography: | http://dx.doi.org/10.1016/j.fcr.2010.05.006 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0378-4290 1872-6852 |
DOI: | 10.1016/j.fcr.2010.05.006 |