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Panax notoginseng (Burk.) F. H. Chen is a significant medicinal plant in China. Its dried roots and rhizomes are rich in triterpenoid saponins (Li et al. 2025) and have been used in traditional Chinese medicine for over 400 years. With increasing market demand, the planting area of P. notoginseng in Yunnan province, China, has reached 24,000 hectares, with an output of 31,000 tons and a comprehensive output value exceeding 20 billion yuan in 2021. In 2024, viral disease-like symptoms including leaf mottling, yellowing, and mosaic were observed on P. notoginseng plants in plantations in Wenshan Prefecture, Yunnan, with an average incidence of approximately 5% (reaching 10% in seedlings). Leaf tissues from three symptomatic and three healthy-appearing plants were collected for analysis. Transmission electron microscopy revealed the presence of flexuous filamentous particles of about 700 nm, characteristic of potyvirus particles, in crude sap extracts from the symptomatic P. notoginseng samples but not from the asymptomatic samples. Total RNA was extracted from leaves of the symptomatic plants using the Eastep® Super Total RNA Extraction Kit (Promega, Shanghai, China) and sequenced by high-throughput sequencing (HTS) on an Illumina NovaSeq 6000 PE150 platform (Biolinker, Kunming, China). A total of 233,152,648 clean reads were obtained using fastp (v0.23.1). The subsequent de novo assembly with SPAdes (v3.15.3) produced 24,018 contigs (>500 bp). BLASTn analysis revealed that four contigs mapped to bidens mottle virus (BiMoV) (PQ374045). The longest (9,680 nt) shared 97.4% nt identity with the BiMoV isolate SF-1 (AF538686). In addition, 4, 4, and 1 contigs mapped to Panax cryptic virus, Panax notoginseng virus A, and clover yellow vein virus, respectively; however, RT-PCR testing yielded negative results for these viruses. Subsequently, the full-length genome sequence of this BiMoV isolate (SQ24YV) was obtained from one of the symptomatic plants using RT-PCR and Sanger sequencing with the specific primers (Table S1), and deposited in GenBank (PV608408). As anticipated, it exhibited 100% identity with the longest contig mentioned above. To confirm the infectivity of BiMoV to P. notoginseng, leaf sap from diseased P. notoginseng and BiMoV infecting-Bidens pilosa was mechanically inoculated into six one-year-old healthy seedlings each of P. notoginseng. The seedlings were grown in a shaded, ventilated greenhouse. At 14 days post-inoculation, the systemic leaves of all the inoculated plants exhibited yellowing and mottling, similar to symptoms observed in the field. RT-PCR with a specific primer pair (BiMoV-CPF/BiMoV-CPR) targeting the CP gene amplified a 608-bp fragment in sap-inoculated plants, but not in mock-inoculated plants. BLASTn analysis of the amplicon sequences upon Sanger sequencing confirmed their BiMoV identity, as they shared 100.0% nt identity with the BiMoV-SQ24YV, thus confirming that BiMoV can infect P. notoginseng plants. P. notoginseng is susceptible to a variety of viral pathogens such as watermelon mosaic virus, cucumber mosaic virus, tomato yellow leaf curl China virus, Panax notoginseng potyvirus, and Panax notoginseng virus A (Wei et al. 2025; Cheng et al. 2024; Yang et al. 2019). This research demonstrates that P. notoginseng is also susceptible to BiMoV. To our knowledge, this is the first report of BiMoV infecting P. notoginseng in China. It provides a new reference for the prevention and control of viral diseases in P. notoginseng.