SSM-Wheat: a simulation model for wheat development,growth and yield

Document Type: Research Paper

Authors

1 Agronomy Group, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan 49138-15739, Iran

2 Agronomy Group, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan 49138-15739, Iran.

3 Department of Crop Science, North Carolina State University, Raleigh, NC 27695-7620, USA.

Abstract

A robust crop model can assist in genetic improvement and cultural
management of the crop. The objectives of this study were to describe a wheat
(Triticum aestivum L.) model and to report results of its evaluation. The model
simulates phenological development, leaf development and senescence, crop mass
production and partitioning, plant nitrogen balance, yield formation and soil water
and nitrogen balances. The model includes responses of crop processes to
environmental factors of solar radiation, temperature and nitrogen and water
availability. Parameters are inputted in describing physiological processes so that
these can be varied to define genotypic differences. The model uses a daily time
step and readily available weather and soil information. The model was tested
using independent data and indicated an acceptable performance for important crop
attributes as compared to observed results including days to anthesis (CV=4.5%;
r=0.98) and maturity (CV=5.6%; r=0.96), crop LAI (CV=11.8%; r=0.80) and dry
mass at anthesis (CV=9.3%; r=0.72) and total crop mass (CV=9.5%; r=0.82) at
maturity and grain yield (CV=8.4%; r=0.89). It was concluded that the model can
be used in simulation studies of wheat yield and its limitations in response to
environmental conditions, management inputs and genetic factors.
Keywords: Wheat; Simulation; Yield; Water; Nitrogen.