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The intricate interplay between endophytic microorganisms and plants in the upkeep of biodiversity, the stability of communities, and the operation of ecosystems needs to be more adequately extensive. Although root-associated microbial communities of plants have been revealed for the last decade, the understanding of bacterial and fungal communities associated with the roots of medicinal plants remains elusive. To highlight the importance of Panax ginseng Meyer (PG) in our research, we investigated the root endophytic bacterial and fungal communities of Panax ginseng Meyer (PG), alongside Aralia cordata (AC), Angelica gigas (AG), and Peucedanum japonicum (PJ), utilizing amplicon-based community profiling and advanced bioinformatic methodologies. The study aimed to investigate the root-endophytic microbiota of ginseng and three other medicinal plants and identify similarities in microbiome composition across different plant species and families. Results revealed that root-endophytic bacterial and fungal communities were influenced by plant species and phylogenetic differences at the family level. Differential abundance tests and random forest models showed microbial features within the same plant family. PG had a distinctive microbial profile with significant B1653_o_Enterobacterales and F8_o_Helotiales. PG had a core microbiome, B10_Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, and a more evenly distributed microbial network compared to AG, PJ, and AC. Our research reveals the intricate endophytic microbial communities within the roots of medicinal plants, pinpointing specific taxa that may be pivotal to their medicinal qualities and overall plant health. These insights carry notable implications for future studies, particularly those focused on the endophytes of PG and their secondary metabolites, as they deepen our understanding of plant-microbe interactions and their role in enhancing the plants' therapeutic potential., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Ethical approval: The research conducted adhered to the guidelines outlined in the IUCN Policy Statement on Research Involving Species at Risk of Extinction and Convention on the Trade in Endangered Species of Wild Fauna and Flora., (© 2024. The Author(s).)

The phloem limited bacterium 'Candidatus Liberibacter solanacearum' (Lso) is associated with disease in Solanaceous and Apiaceous crops. This bacterium has previously been found in the UK in Trioza anthrisci, but its impact on UK crops is unknown. Psyllid and Lso diversity and distribution among fields across the major carrot growing areas of Scotland were assessed using real-time PCR and DNA barcoding techniques. Four Lso haplotypes were found: C, U, and two novel haplotypes. Lso haplotype C was also found in a small percentage of asymptomatic carrot plants (9.34%, n = 139) from a field in Milnathort where known vectors of this haplotype were not found. This is the first report of Lso in cultivated carrot growing in the UK and raises concern for the carrot and potato growing industry regarding the potential spread of new and existing Lso haplotypes into crops. Trioza anthrisci was found present only in sites in Elgin, Moray with 100% of individuals harbouring Lso haplotype C. Lso haplotype U was found at all sites infecting Trioza urticae and at some sites infecting Urtica dioica with 77.55% and 24.37% average infection, respectively. The two novel haplotypes were found in Craspedolepta nebulosa and Craspedolepta subpunctata and named Cras1 and Cras2. This is the first report of Lso in psyllids from the Aphalaridae. These new haplotypes were most closely related to Lso haplotype H recently found in carrot and parsnip. Lso was also detected in several weed plants surrounding carrot and parsnip fields. These included two Apiaceous species Aegropodium podagraria (hap undetermined) and Anthriscus sylvestris (hap C); one Gallium sp. (Rubiaceae) (hap undetermined); and Chenopodium album (Amaranthaceae) (hap undetermined).

Candidatus Liberibacter solanacearum (Lso) is bacterium transmitted by psyllids to Solanaceae and Apiaceae plants. So far, Lso is found in Europe affecting Apiaceae. In the Mediterranean region, Bactericera trigonica is the only known vector of Lso, but the leek-onion psyllid Bactericera tremblayi is another widespread psyllid and potential vector of Lso. Commonly, carrot, leek and potato are cultivated in the same zones and it is uncertain if these psyllid species are able to transmit Lso to potato plants. Here, we assessed the transmission of Lso by B. trigonica and B. tremblayi to potato plants. B. trigonica showed preference to ingest from the phloem, settle and oviposit on carrot and celery but not on potato. This was correlated with high Lso transmission rates to both carrot (80%) and celery (70%) but very low to potato (≤3%). B. tremblayi preferred leek over carrot and potato, the latter being the less preferred host. B. tremblayi readily ingested from the phloem of infected carrots but failed to transmit Lso from carrot to carrot. Our study shows that the risk of Lso transmission from Apiaceae to potato by B. trigonica is very low, and that B. tremblayi is not a likely vector of Lso.