MATHEMATICAL MODELLING OF THE FAST DYNAMIC RESPONSE OF TOMATO LEAVES TO SUDDEN CHANGES IN MICROCLIMATE

All living plants are influenced by their local microclimate (e.g. light intensity, temperature, etc.), and they respond dynamically to environmental changes.
When it is the aim to optimise a biological process (photosynthesis, transpiration, etc.), this can be realised by controlling the microenvironment around the organism.
Therefore a compact dynamic model, taking into account the response of the organism as an on-line feedback, is absolutely necessary.
The integration of these dynamic data-based modelling techniques with new hardware and sensor techniques should make it possible to realise more efficient model predictive control and the continuous monitoring of bioprocesses.
The objective of this study is to explore the possibility of modelling the fast dynamic response of net photosynthesis of leaves on a tomato plant to sudden step changes in light intensity, using a dynamic simple transfer function model.
The models were evaluated using the coefficient of determination (r²) and the Young’s Identification Criterion (YIC). The mathematical analysis showed that the dynamic response on light switching on was best described by a third order model and on light switching off by a second order model (r² = 99.8%). Additionally, the asymmetry of the response in time to step changes up (e.g. light on) and down (e.g. light off) was investigated.
Moreover a physiological explanation is formulated for the complexity of the responses.

XXVI International Horticultural Congress: Protected Cultivation 2002: In Search of Structures, Systems and Plant Materials for Sustainable Greenhouse Production

C. Boonen, J.-M. Aerts, D. Berckmans, H. Pien, R. Lemeur, P.C. Young

data-based modelling, transfer function model, YIC, plant dynamics, microenvironment, bioresponse, model order

https://doi.org/10.17660/ActaHortic.2004.633.26