Bringing Europe's early career plant scientists back together

The European Plant Science Retreat (EPSR) came into existence in 2008 to provide opportunities for early career plant scientists to develop their scientific network. Before the COVID-19 pandemic, the EPSR occurred annually in various countries, including Belgium, France, Germany, the Netherlands, Spain, and the United Kingdom, strengthening the interactions between early career plant scientists (van der Horst et al., 2019). This event, organized by and for PhD candidates, provides an accessible environment for PhD candidates to showcase their work and participate in discussions where they might be reluctant to do so with established scientists present. This year the EPSR resumed after a 3-yr hiatus, bringing Europe's early career plant scientists back together at Wageningen University (the Netherlands). Close to 70 PhD candidates from nine different countries participated (Fig. 1a). In addition to poster presentations and talks from PhD candidates, there were inspiring talks given by invited speakers, workshops, and excursions. In this report, we as the organizing committee share some of the highlights of this year's EPSR. The topics of the participant's presentations covered a wide range of research areas spanning plant development and responses to (a)biotic stresses, evolutionary biology, genetics, biophysics, and biotechnology (Fig. 1b). The diversity extended beyond the subjects themselves, encompassing a broad spectrum of plant species, microbes (Fig. 2) and research techniques. Despite this variety, many research topics were found to be interconnected. For example, Prof. Bert de Rybel (VIB, Ghent) presented how he and his team apply single-cell RNA sequencing (scRNA Seq) to investigate the molecular mechanisms of vasculature development in land plants. Cytokinin-related control of transcriptional networks guides the de novo organogenesis in vascular development (Smet et al., 2019). In the same theme, Sophia Müller (Wageningen University, the Netherlands) presented the usage of scRNA technology to unravel the molecular mechanism behind nodule initiation in Medicago truncatula, which is also regulated in part by cytokinin. She presented her experience in using single protoplast vs single nuclei samples for sequencing and the challenges both methodologies entail. This new technology brings exciting new possibilities, together with a new set of challenges to overcome. Cytokinin signaling was further featured in posters and talks on abiotic stresses, like salinity and drought, that are increasingly threatening agricultural production. In her research, Katrina Leslie Nicolas (Masaryk University, Czech Republic) used natural variations in cytokinin-responsive histidine kinases to study drought stress resistance in Arabidopsis thaliana. Accessions possessing a higher sensitivity to cytokinin were found to sense drought stress earlier which caused stronger inhibition of root growth under drought conditions. On the contrary, accessions with lower sensitivity were less inhibited in their growth. Alesia Melnikava (Masaryk University, Czech Republic) showed that DIRIGENT PROTEIN 13, is involved in promoting lateral root growth and development in A. thaliana. DIR13 is induced by cytokinin signaling and its conferred increased tolerance to salt stress. These studies show that fine-tuning the sensitivity to hormone response may offer a strategy for synthetic biology to increase crop resistance to abiotic factors. In addition to abiotic factors, several participants conduct research on how plants interact with light. Elizabeth van Veen (Wageningen University, the Netherlands) showed how salinity has an impact on various aspects of skotomorphogenesis and the establishment of A. thaliana seedlings in the dark. Dark-grown seedlings exposed to salinity display abnormal skotomorphogenesis, which may hinder the ability of a seedling to establish in the local environment and become photoautotrophic. The plant's interaction with light has many biochemical aspects, as demonstrated by Umama Hani (University Paris-Saclay, France). She showed in her research that the regulation of O2 reduction at photosystem I (PSI) is daylength dependent. The reactive oxygen production was significantly higher for plants grown under short-day conditions compared to plants grown under long-day conditions. The differences in redox regulation of O2 reduction are influenced by two factors: the composition and the localization of specific proteins within thylakoids in the stroma. With her work, she contributed to our understanding of a regulatory mechanism that is likely to be important for photosynthetic acclimation. To facilitate the study of photosynthesis further, Sanchali Nanda (Umeå University, Sweden) developed a tool, named Chlorospec, a novel chlorophyll spectrometer which can simultaneously measure time- and wavelength-resolved fluorescence signals, which may become a new standard tool in photosynthesis research. Another major threat to agricultural production is biotic stress. Prof. Jane Parker (Max Planck Institute Cologne, Germany) presented her career-spanning work on how plants control their innate immune response. A part of this immune response are Toll/interleukin-1/resistance (TIR) domain-containing receptors, which produce small nucleotide-based messenger molecules to initiate responses like cell death and important transcriptional changes in Arabidopsis (Huang et al., 2023). Gabriella Petti (University Cologne, Germany) presented another form of plant immune response. Plants can produce antimicrobial peptides which are secreted into the environment. These peptides are called plant natriuretic peptides (PNPs) and are widespread across the whole plant kingdom. A similar strategy is used on the pathogen's side as well, as was shared by Anton Kraege (University Cologne, Germany). The fungal pathogen Verticillium dahliae secretes an Av2 effector with antimicrobial activity to manipulate the soil microbiota as well as its host plant to ultimately promote disease development and invade the plant. In addition to scientific content, PhD candidates were invited to discuss scientific integrity. Pressure to publish generates incentives that sometimes do not support rigorous science. In the worst case, this can lead to scientific misconduct, as exemplified by image manipulation or AI-driven paper mills. Elisabeth Bik, a well-known science integrity consultant, provided an insightful talk on the importance of truthfulness, transparency, and adherence to ethical principles when reporting and disseminating research. Her work underscores the importance of maintaining the transparency and reliability of scientific research. This in turn has direct implications for the trustworthiness of scientific findings and their impact on society. Keynote talks were especially inspiring when speakers opened up about their own (early) academic and personal journey to their current position. We received a great deal of positive feedback on the inspirational talk by Jose Lozano Torres in which he combined a story on how nematode-induced jasmonic acid signaling networks promote stem cell activation and regenerative processes (Zhou et al., 2019), with personal anecdotes from conducting this research. The combination of excellent science and transparency on setbacks and moments of great happiness in both professional and personal life was refreshing. The points of advice sprinkled throughout resonated with an audience that will soon be deciding on the next steps in their career. The theme of openness was embraced at the event, with some PhD candidates openly sharing their struggles in dealing with the stress that inevitably comes with a PhD project. The environment that facilitated this openness might in part have been created by a workshop given by Ana Pineda on how to deal with this stress in a healthy and productive manner. Her approach, in which she combines time management and meditation exercises to build habits that foster productivity and happiness (Pineda, 2020), has been reported broadly by participants as one of the applicable learning experiences they took home. The wellbeing of graduate students has been of increasing concern in recent years (Evans et al., 2018), and providing accessible tools to empower PhD candidates to improve their wellbeing can be part of the solution. As an organizing committee, we look back at the EPSR with fond memories and pride. We are impressed by the quality of research presented and the openness of participants. Organizing the EPSR has been a rewarding and inspiring experience for us in which we gained our first experiences in arranging funding, logistics, inviting speakers, and moderating discussions for an event like this. This has been a great learning opportunity, that we can recommend to any PhD candidate. It was great to be in the middle of this community of young scientists for a few days. We are looking forward to the next edition of the EPSR in Paris in 2024. The authors are grateful to the Graduate School of Experimental Plant Sciences (EPS), the Dutch Research Council NWO-ENW-WBO2022-1.20735 grant, KeyGene, KWS Vegetables, BMKgene and the New Phytologist Foundation for their financial and in-kind support of the EPSR 2023. Furthermore, they would like to thank all the speakers, workshop leaders and panelists for their participation. Finally, the authors would like to especially thank Juliane Teapal and the EPS office for their constant organizational support, and Alessio Albanese for his help in organizing the EPSR. JW and KD wrote the report, SM and RCMK designed the figures. All authors have read and approved the report.