Microbial Ecology and Evolution Research group led by Professor Ville-Petri Friman at the Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki is looking for a postdoctoral researcher with background in molecular virology, microbiology and metagenomics/metaviromics to a Jane and Aatos Erkko Foundation funded project: ‘Discovering the benefits of plant growth-promoting bacteriophages
Plant growth is not only determined by the plant genotype but also by the presence of beneficial microbes that can boost plant growth by providing access to nutrients, defending plants against invading pathogens, and producing plant growth-promoting hormones. While increasing evidence suggests that phages can shape the composition, diversity and functioning of rhizosphere bacterial communities, we lack an understanding of how these changes are associated with plant health and growth. The main aim of this project is to experimentally study how phages can boost plant growth and to determine the underlying genetic and molecular mechanisms of phage-mediated plant growth-promotion.
Even though phages do not directly interact with plants, they can indirectly affect plant growth by interacting with plant-associated rhizosphere bacteria. For example, lytic phages can infect and kill plant-pathogenic bacterial taxa and reduce their relative abundances alleviating plant disease symptoms. Selective killing of bacterial taxa can also lead to the enrichment of plant growth-promoting bacteria in the rhizosphere, which could result in improved plant growth. Moreover, by killing bacteria, lytic phages release nutrients in the rhizosphere, which could help plants sequester and assimilate resources to support their growth. Finally, temperate phages can integrate into bacterial chromosomes and provision bacteria with additional genes (auxiliary metabolic genes, or AMGs for short) that do not only improve bacterial survival but could also boost the expression of plant growth-promoting functions.
In this project, we will use a highly trackable tomato rhizosphere model system to directly study if phages can boost plant growth by interacting with rhizosphere bacterial communities in the plant roots. Specifically, we will focus on understanding the importance of three key mechanisms of phage-mediated plant growth-promotion: i) Release of nutrients in the rhizosphere due to the killing of bacteria by phages, ii) Selective enrichment of plant growth-promoting bacteria in the rhizosphere by phages, and iii) Provisioning of bacteria with plant growth-promoting functional genes by temperate phages.
We are seeking a highly motivated and enthusiastic postdoctoral researcher with experience in molecular virology, microbiology and metagenomics/metaviromics to join our international team. The candidate should hold PhD degree in microbiology, bioinformatics or related field, and good written and verbal communication skills in English are necessary. The postdoctoral position is for 4 years starting in April 2026.