The optimisation of root systems in plant populations is an important starting point for optimising water and nutrient use efficiency in order to make agricultural ecosystems more resilient to extreme weather events such as drought stress and to minimise nutrient losses. The ‘CROP’ research project aims to improve the resilience of agricultural systems to drought stress and to increase carbon stabilisation in the soil and nitrogen use efficiency.
The central approach is the combined cultivation of wheat varieties with complementary root systems (shallow-rooted and deep-rooted). The interdisciplinary research team combines laboratory and field experiments with mathematical modelling to analyse exchange and transport processes of water, carbon and nitrogen as well as microbial abundance and activity in the soil-plant system.
The results to date show that complementary root system architectures can be realised with suitable wheat varieties. Cultivation of the deep-rooted wheat genotype increased water uptake and microbial enzyme activity in deeper soil layers. This result indicates a beneficial effect on water uptake dynamics and microbial nutrient turnover. The mathematical model enabled the simulation of plant architecture and growth, photosynthesis, coupled water and matter fluxes within the plant, rhizodeposition and the growth and activity of microorganisms in the soil.
In the second phase of the project, the project partners are testing the new cultivation system with two central field experiments under nitrogen limitation and drought stress. The integrated structural-functional plant and soil microbiome model will be expanded to include two key processes (release of biopolymers, growth of arbuscular mycorrhizal fungi). CROP thus contributes to a better understanding of the benefits of variety mixtures with complementary root architectures and provides a forecasting tool.
