RT Dissertation/Thesis T1 The role of soil properties and fertilization management in pathogen defense and plant microbial interactions in the rhizosphere of lettuce (Lactuca sativa L.) A1 Windisch,Saskia Helen WP 2022/11/02 AB Soil microorganisms are involved in nearly all relevant soil processes and considered as key players in agro-ecosystems. This is particularly relevant for the rhizosphere which is created by the activity of plant roots with dynamic impact on microbial communities, their diversity and activity. Both, beneficial but also pathogenic plant-microbial interactions in the rhizosphere are driven by root exudates and other root-induced modifications in rhizosphere chemistry, which are highly variable in space, time, composition and intensity. The physicochemical properties of the rhizosphere are influenced by numerous external factors including nutrient availability, biotic and abiotic stress, soil properties or plant genotypic variation but the related consequences for plant-microbial interactions and the consequences for plant performance and health status are still poorly understood. In this context the present study was initiated to investigate (i) the influence of the soil type on root exudation and the composition of the rhizosphere solution (ii) their impact on interactions with soil pathogens and beneficial rhizosphere microorganisms and (iii) the effect of long-term fertilization strategies (organic vs. mineral fertilization), using lettuce (Lactuca sativa) as a well-characterized model plant for studies on plant-microbial interactions in the rhizosphere. K1 Salat K1 Pflanzen K1 Düngung K1 Rhizosphäre K1 Mikroorganismen PP Hohenheim PB Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim UL http://opus.uni-hohenheim.de/volltexte/2022/2071