A drought tolerant synthetic bacterial community for barley

• Applicant: Professor Dr. Mika Tarkka
• Subject Area: Plant Breeding and Plant Pathology ; Microbial Ecology and Applied Microbiology ; Plant Cultivation, Plant Nutrition, Agricultural Technology
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 466312020

Drought events are predicted to increase in frequency and intensity, and thereby cause a challenge for agricultural production. As drought responses in plants are combined with changes in plant-associated microbiomes, an emerging idea is that the adapted microbiome can be used to increase plant fitness. The proposed project investigates mechanisms of interactions between a synthetic bacterial community and barley under drought stress. It focuses at the levels of bacterial and barley gene expression and measures of barley drought tolerance. Not having been part of the original DECRyPT consortium, this project for the reconstruction phase of the priority program is based on extensive preliminary work. It is centred on a collection of 16 genome-sequenced drought-tolerant bacteria that are enriched in barley rhizospheres in response to drought (DT-SynCom). The bacterial community was selected from functionally characterized isolates based on amplicon sequencing analyses of a field and a pot experiment. The project aims at mechanistic insights into the interactions among the bacteria, as well as the local responses of barley roots to the DT-SynCom and systemic feedback in shoots. First, the influence of the bacteria on growth and drought tolerance of barley is evaluated and related to bacterial and plant gene expression. Then, the influence of the presence of other barley-associated bacteria (HvSynCom) and of a drought-tolerant host genotype on the performance of the DT-SynCom is assessed. Third, responses of the system to abiotic factors are analysed in two different soils and at moderate and high temperatures. Finally, collaborative experiments investigate how the DT-SynCom affects a beneficial interaction of barley with a fungal root endophyte, and whether it induces local or systemic disease resistance under drought or control conditions.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2125: Deconstruction and Reconstruction of the Plant Microbiota "DECRyPT"
• Co-Investigators: Dr. Anna Heintz-Buschart; Dr. Thomas Reitz