Noise-Induced Phenomena and Complex Rhythms: A Test Scenario for Plant Systems Biology

Combining the unravelling of the molecular bases of functions in time and of organization in space in biology, on the one hand, with nonlinear dynamics as part of theoretical physics, on the other, is promising great progress in basic understanding of nonlinear spatial pattern formation from huge amounts of data becoming available in systems biology . In this chapter, this will be assessed in terms of the “tripod” (1) experimentation, (2) modelling and (3) theory. 1. Empirical case studies of rhythmicity are derived from three areas of study, (i) Crassulacean acid metabolism, (ii) stomatal pore regulation by guard cells and (iii) plant memory. Biorhythmicity is underlying the former two, whose spatiotemporal dynamics can be documented by, among other techniques, chlorophyll fluorescence imaging. The third one, plant memory, is intimately related to rhythmicity and the biological clock with its set points and phase regulation. All three case studies reveal nonlinear performance with synchronization /desynchronization leading to modelling and theoretical concepts. 2. In modelling, maximal models, providing perfectionist “photographic” imaging of nature, are distinguished from minimal models singling out essential domains in the parameter space of systems, with heuristic aims. The latter are explored in approaches based on experiment/theory feedback . 3. Theoretical assessment dwells on the method of cellular automata , which are frameworks for simulating spatiotemporal patterns arising from local interactions. The theoretical concepts developed are based on the examination of stochasticity with the order-generating effects of noise in stochastic resonance and coherence resonance, where intermediate noise intensity generates quasi-rhythmic behaviour of systems from arrhythmicity.