Endophytes are microbes capable of colonizing the inner part of different plant tissues without causing disease symptoms. In some cases, they have beneficial effects for the host plant. The role of endophytes in biological control of plant pathogens, in induction of plant abiotic stress tolerance and in enhancement of plant growth has strongly increased the focus on the isolation of novel endophytic species. In order to implement the use of specific endophytes in agriculture, it is important to understand the mechanisms involved in the plant-endophyte interactions. Phytohormones play a significant role in this interaction, but little is known about the specific way by which they influence the recruitment and the colonization of the host tissues. The aim of the current project is to go deeper into the role of these signalling compounds in plant-endophyte interactions.
The isolation of endophytic fungi from tomato (Solanum lycopersicum) mutants impaired in synthesis of specific phytohormones (specifically ethylene and jasmonic acid) was the first step taken to elucidate these complex mechanisms. The isolation of endophytes was performed from roots and it resulted in the selection of fungal isolates whose root-colonization frequency appears to be influenced by the presence/absence of specific phytohormones. In order to obtain a deeper understanding of the role of these compounds in the plant-endophyte interaction, the selected isolates are currently being screened using confocal microscopy and qPCR in order to find candidates whose colonization rate is critically affected by the phytohormones of interest.
A transcriptomic analysis of tomato plants inoculated with the isolates selected from the screening will provide further clues as to which physiological mechanisms, associated with endophyte recruitment, are influenced by phytohormones.
“This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 676480”.