Project: Unravelling the mechanisms underlying health and productivity promoting agricultural practices by fine-mapping rhizosphere communities

Land use practices, such as organic amendments, reduced tillage and crop rotation, promote the growth and development of plants by changing the diversity and abundance of soil microbiota. Recently, it has been shown that plants recruit specific rhizosphere microbiomes from the bulk soil reservoir ('niche theory'). Hence, plants have developed species-specific mechanisms to select and foster specific parts of the microbial community. However, the effect of agricultural practices on rhizosphere communities and their food web structures has hardly been addressed for crops. This proposal includes a detailed characterisation of the rhizosphere community at the taxonomical level under field conditions for two dicots (potato and pea), two monocots (leek and barley), and one gymnosperm (taxus). Hereto, we will take advantage of long-term field experiments comprising a variety of soil management strategies. The focus will be on quantitatively the most relevant functional groups within the 1st and 2nd trophic layer of the soil food web (i.e. bacteria, fungi, protozoa, and nematodes). For this, we will exploit the high resolution-power offered by the combined use of next-generation sequencing and quantitative PCR. The goal is to obtain insight in the effects of easily transferable soil management practices (e.g., tillage and compost input) in shaping the food web structure in the rhizosphere. These insights will allow us to develop diagnostic assays to provide robust crop-specific advices for the optimal and durable utilisation of soil life."