Nutrient uptake and root system architecture modeling: Past and prospects for the future

Modeling is an essential step in understanding plant root systems (Fitter 1991, 1996, 2002). The inherent difficulties in measuring root system structure and function make modeling uniquely important for this field of research. Traditionally, there has been a division between modeling root system shape (cf., Berntson 1996; Lynch and Nielsen 1996; Pagès 2002) and modeling of physiological processes carried out by plant roots (cf. Silberbush 1996, 2002; Sperry et al. 2002). In recent years, the tendency has shifted toward combined structural-functional models. These include an architectural element simulating the structural development of the root system with functional simulation of physiological and ecological processes at the root-soil interface. In this chapter, we review techniques used for modeling nutrient uptake and root-rhizosphere interactions. Later, we describe modeling of root system structure and function in 3D space using SimRoot as an example (Lynch et al. 1997). A brief account of future simulation needs concludes this chapter.