Simulation of wheat growth and development based on organ-level photosynthesis and assimilate allocation

Abstract

Intimate relationships exist between form and function of plants, determining many processes governing their growth and development. However, in most crop simulation models that have been created to simulate plant growth and, for example, predict biomass production, plant structure has been neglected. In this study, a detailed simulation model of growth and development of spring wheat (Triticum aestivum) is presented, which integrates degree of tillering and canopy architecture with organ-level light interception, photosynthesis, and dry-matter partitioning. An existing spatially explicit 3D architectural model of wheat development was extended with routines for organ-level microclimate, photosynthesis, assimilate distribution within the plant structure according to organ demands, and organ growth and development. Outgrowth of tiller buds was made dependent on the ratio between assimilate supply and demand of the plants. Organ-level photosynthesis, biomass production, and bud outgrowth were simulated satisfactorily. However, to improve crop simulation results more efforts are needed mechanistically to model other major plant physiological processes such as nitrogen uptake and distribution, tiller death, and leaf senescence. Nevertheless, the work presented here is a significant step forwards towards a mechanistic functional-structural plant model, which integrates plant architecture with key plant processes.

Exploring the Vertical Distribution of Structural Parameters and Light Radiation in Rice Canopies by the Coupling Model and Remote Sensing

“…Mathematical functions and three-dimensional structures of computer simulation modeling methods are commonly used to simulate the light radiation distribution in the crop canopy [30][31][32]. The Beer-Lambert law proposed by Monsi and Saeki [7] is one of the most popular classical models for simulating light radiation distribution.…”

CN-Wheat, a functional–structural model of carbon and nitrogen metabolism in wheat culms after anthesis. I. Model description

“…Temperature dependence of photosynthetic parameters is accounted for by using Arrhenius functions. Calculation of organ temperature (Supplementary Data 2) was adapted from Evers et al (2010). Briefly, this method is based on the Penman-Monteith equations, whereby organ temperature is calculated from the net absorption of radiation, transpiration and resistance to heat estimated from wind, organ width and height.…”

“…Most present FSPMs have mainly addressed the representation of realistic plant architecture to assess interactions with the (a)biotic environment (SaintJean et al, 2004;Cici et al, 2008;Robert et al, 2008;Barillot et al, 2014). Based on calculations of local light interception, various FSPMs account for the assimilation of carbon, but assimilate partitioning is generally solved using a supply-demand approach whereby the supply synthesized by sources is shared among sinks according to their 'demand' (Luquet et al, 2006;Evers et al, 2010;Sarlikioti et al, 2011;Bertheloot et al, 2011). By contrast, an example of mechanistic treatment of sink-source relations for C has been proposed by Allen et al (2005).…”

Oscillations in Functional Structural Plant Growth Models

“…Indeed, this model focuses on processes that are generic enough to be applied to most plant species (biomass prodution and allocation, coupled with the plant topological development); its main principles are shared by several other 'carbon-driven' models (e.g. TOMSIM [10], one extension of the ADELwheat model [5] or EcoMeristem [18]) so parts of this work can be generalized; changes in plant topology are dynamically simulated in interaction with the plant physiological state, which allows modelling phenomena such as fruit abortion or branch appearance. Besides, a strong effort was put on its rigourous mathematical formalization, thus paving the way to the study of its behaviour.…”