Should be Taken into Account the Plant Azimuth to Estimate the Light Phylloclimate within a Virtual Maize Canopy?

Function-Structure Plant models (FSPM) usually describe accurately the plant geometry, but less accurately the inter-plant geometry. Indeed, simulating an actual inter-plant geometry would require simulating how neighbor plants “interact” to colonize free space with their respective organs. Thus, the question of how accurate the inter-plant geometry needs to be taken into account arises. This question comes partly from the required accuracy for the simulation of physical transfer within virtual canopies. The present study focuses on the relative azimuths of maize plants and their effects effect on light interception at various scales. Results showed low effects at canopy and leaf rank scale, higher effects at individual plant scale, and significantly at individual leaf scale. They raise two questions: how reliable are FSPMs using leaf irradiance but not taking into account inter-plant geometry and how validate the canopy architecture component of FSPMs has to be validated regarding leaf irradiance estimation, knowing that canopy-scale light variables such as ground cover, are not well suited?