RootWayS 2

Deep-rooting intercropping systems: Creating highways to subsoil water and nutrient resources

01/04/2024 to 31/03/2027

This subproject of RootWayS targets nutrient turnover, with focus on nitrogen, at the interface of winter cover crop, partially continued as living mulches intercropping, and maize as the main crop with its potential mycorrhizal partners. In the framework of this subproject nutrient cycles shall be elucidated by four working packages: 1) To which degree do winter cover crops contribute to the maize N nutrition? Which proportion of N comes from them? Does coupling of winter-hardy and winter-killed cover crops significantly reduce winter/spring N leaching to enable a higher proportion of cover crop-derived N to be used by maize? 2) Do residue-free root channels of winter-killed cover crops further enhance the access to subsoil nutrient resources? 3) Similrarly, do they enhance the access to subsoil water resources, which supports resistance during long drought periods? 4) Which role does mycorrhiza play to enhance nutrient uptake, i.e. do cover crops modify abundance or community of the Glomermycota and their infection of maize roots? And do living mulch systems directly allocate N to maize via a joint mycorrhizal network?
By these work packages, this subproject analyzes divers plant-soil-microbiome-plant interactions between cover crops (living mulches) and maize, which are quantitatively analyzed and whose relevance for the maize nutrition and drought resistance via the use of subsoil resources is identified.