Submitted to: Abstract of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: August 3, 2002
Publication Date: October 20, 2000
Technical Abstract: Soil, water, solute, heat, and gas transport processess are often simulated with convective-dispersion or diffusion-type equations. These models have to be coupled with a root activity model to simulate plant development. To make such coupling easier, a generic convective-dispersive model of root growth and proliferation was proposed. The submodels of root growth rates and root convective and dispersive propagation rates were built so that a statistical hypothesis testing could be used to reject hypotheses about dependencies of the rates on root and soil variables. Our objective was to test this model with corn plants grown in a greenhouse. Fertilizer application and irrigation varied in treatments. Plant development was monitored weekly by the destructive sampling for 45 days after emergence. Root concentrations were determined in 24 sections of the pots along with shoot parameters. The modular soil and root process simulator 2DSOIL was used to simulate root development. The model explained 73-77% of variation in the values of the logarithm of the root concentration. The hypothesis that root diffusivity did not depend on root concentration could be rejected. Hypotheses about the absence of the geotropic root development and about the decrease of the root growth rate with the growth of root concentration could not be rejected.