Modeling maize production under growth-stage based deficit irrigation management with RZQWM2

Authors: Zhang, Huihui; Ma, Liwang; Mankin, Kyle; HAN, MING - University Of Waterloo; Trout, Thomas

Submitted to: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/19/2021
Publication Date: 1/26/2021
Citation: Zhang, H., Ma, L., Douglas-Mankin, K.R., Han, M., Trout, T.J. 2021. Modeling maize production under growth-stage based deficit irrigation management with RZQWM2. Agricultural Water Management. 248. Article e106767. https://doi.org/10.1016/j.agwat.2021.106767.
DOI: https://doi.org/10.1016/j.agwat.2021.106767

Interpretive Summary: Farmers are challenged to maintain yield and economic productivity with declining water resources and climatic variability in arid and semi-arid regions worldwide. Growth stage-based deficit irrigation has been suggested as a feasible approach to maintain yields with less water. Experiments were conducted in 2012, 2013, and 2015 in which corn was irrigated under twelve treatments with varied levels of irrigation treatments during the late vegetative and maturation growth stages in Northern Colorado. An agricultural system model was used to simulate the effects of growth-stage based deficit irrigation on corn production and yield components. The results showed that the model could simulate the impact of air temperature on maize growth but did not response to the impact of water stress on crop maturity. Both simulated and observed aboveground biomass, grain yield, kernel weight decreased with the decrease of irrigation water amount during the late vegetative and maturation periods.

Technical Abstract: Farmers are challenged to maintain yield and economic productivity with declining water resources and climatic variability in arid and semi-arid regions worldwide. Growth stage-based deficit irrigation has been suggested as a feasible approach to maintain yields with less water. Experiments were conducted in 2012, 2013, and 2015 in which maize (Zea Mays L.) was irrigated under twelve treatments with varied levels of deficit irrigation during the late vegetative (Lveg) and maturation (Mat) growth stages in Northern Colorado. The Root Zone Water Quality Model-CERES-Maize (RZWQM2) model was used to simulate the effects of growth-stage based deficit irrigation on maize production and yield components. The results showed that RZWQM2 could simulate the impact of temperature on maize phenology but did not simulate the impact of water stress on maize maturity. Both simulated and observed aboveground biomass, grain yield, kernel weight decreased with the decrease of irrigation water amount during the Lveg and Mat periods. In general, the simulated aboveground biomass and grain yield showed larger errors in terms of root mean square error, relative RMSE, and Nash-Sutcliffe efficiency, than those reported in the previous modeling studies where deficit irrigation was applied uniformly throughout the growing seasons in the same field. Future efforts to improve the effects of deficit irrigation on kernel development in will likely make RZWQM2 a better decision to the optimize irrigation management in arid and semi-arid regions.