Towards universality and modularity: a generic photosynthesis and transpiration module for functional structural plant models

Functional Structural Plant Models (FSPMs) that combine functional and architectural submodels within the framework of an organ-based plant model are typically rather complex. To successfully overcome this problem, FSPM development requires establishing strictly modular model structures. In particular, physiological submodels should be generic and universal for different plant species, solidly tested and parameterized, provide clearly defined input-output interfaces, and facilitate the exchange between different research groups. To this end, here we present a generalized version of the nitrogen-sensitive LEAFC3-N model of the coupled CO2, H2O and radiation fluxes (Müller et al., 2005, 2006) that was designed to meet this requirements. The model combines and extends recent developments in ecophysiological leaf gas exchange modelling (for review, see Müller et al., 2005). It was tested and calibrated for leaves of wheat (Triticum aestivum L.), leaves and pods of oilseed rape (Brassica napus L.), and leaves and awns of barley (Hordeum vulgare L.). Adaptation to further plant species and organs is planned in future. The barley LEAFC3-N version was integrated into an FSPM of this crop (Wernecke et al., 2007). Here we discuss aspects of the universal formulation and parameterization of the LEAFC3-N model for different plant species and organs and its integration into FSPMs.