FROM MOLECULAR PROCESSES TO PLANT POPULATION FUNCTIONING: TOWARDS INTEGRATIVE BIOLOGY IN HORTICULTURE

Biological systems can be described as consisting of “layers of perception”, in which each layer can be approached using a discipline and a dedicated set of data and processes. A deliberate choice is made to perceive the system investigated through the filter of a discipline, one or two scales, and an appropriate “tool of the trade”, measuring a restricted set of output variables while neglecting most others. The same applies to horticultural production systems, yet horticulture is by its very nature multidisciplinary and multi-scaled: research in horticulture is carried out at the interface between different subjects (botany, genetics, agro-ecology, physiology, physics, etc.) and at different scales (molecular, cellular, tissue, organ, shoot, plant, stand, etc.). The advent of new regulations in horticulture entails new challenges for all members of the production chain, including researchers. Sustainable horticulture is to become the standard, and this will require a different, integrated, “systems biology” perception of horticulture: integrative biology.
Having already been applied to model the structural and physiological dynamics of a diverse range of agricultural and horticultural crop plants, functional-structural plant modelling (FSPM) is a paradigm which lends itself as a suitable tool in the quest towards horticultural systems biology.
In this paper we will introduce FSPM and show, using the cut-rose and apple orchard production systems as examples, how an integrated, multiscale, perception of a horticultural system and its implementation as a spatially and functionally explicit computer model can help in decision support and as a tool for advancing fundamental physiological knowledge.