Humboldt-Universität zu Berlin - Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences

In all agricultural systems and in growers' fields, growing plants constantly interact with the microclimate created by their neighbouring plants by adapting their morphological and physiological characteristics. The capacity for these adaptations, i.e. phenotypic plasticity, is essential for resource acquisition, plant-plant competition and the fitness of individual plants in the stand. Experimental methods that quantitatively decompose the effects of these plant-plant interactions on individual plant and stand performance into physiologically interpretable parameters are surprisingly scarce to date. We propose to use recent advances in phenomics and 3D modelling to understand the strategies of phenotypic plasticity of plant-plant interactions and their functional effects on stand productivity. We will use 228 winter wheat genotypes to test seven main hypotheses related to the effects of plastic acclimation of leaf, stem and root traits on resource acquisition, fitness of individual genotypes in a heterogeneous stand and overall canopy productivity. Genome-wide association studies will be used to identify the genomic regions responsible for the plastic or invariant response of a trait to environmental variation. It is expected that our work will provide insights into the design of agricultural systems (e.g. varietal mixing) and selection bias due to competition between plants in breeders' fields.