Root rot disease significantly reduces the medicinal quality of Coptis chinensis . In the present study, results found that the C. chinensis fibrous and taproot have different tactics in response to rot pathogen infection. Diaporthe eres , Fusarium avenaceum , and Fusarium solani were isolated and identified to cause different degrees of C. chinensis root rot. These results are helpful for researchers to further explore the mechanism of resistance to rhizoma Coptis root rot.

Outbreaks of leaf spot disease occurred in Rehmannia glutinosa fields in Henan Province, China, in 2019, with the incidence ranging from 20% to 40%. R. glutinosa plants with diseased leaves were collected, and 25 isolates were obtained. Pathogenicity tests, morphological observations, and phylogenetic analyses were conducted to identify the pathogens, and the biological characteristics and control agents of the pathogens were studied. Five isolates of pathogenic fungi were isolated. Three isolates were identified as Fusarium equiseti, which is a new pathogen causing R. glutinosa leaf disease; the other two isolates were identified as Fusarium acuminatum. The mycelia of F. equiseti grew fastest on Czapek medium, and the optimal temperature and pH were 25 °C and 10.0, respectively. The mycelia of F. equiseti grew from 5 °C t o 35 °C, and the lethal temperature was 55 °C. The optimal carbon and nitrogen sources were soluble starch and peptone, respectively. Eight fungicides had inhibitory effects on the mycelial growth of F. equiseti and F. acuminatum. Prochloraz had higher activities against F. equiseti and F. acuminatum, with EC₅₀ values of 0.139 mg·L⁻¹ and 0.123 mg·L⁻¹, respectively. These results provide useful information that will aid the development of management strategies to control leaf diseases of R. glutinosa caused by F. equiseti and F. acuminatum.

Lily virus X (LVX) is a positive-sense ssRNA virus belonging to the genus Potexvirus in the family Alphaflexiviridae. LVX is known to infect plants of the genera Lilium and Tricyrtis in the family Liliacea. LVX was first reported in an asymptomatic lily (Lilium formosanum) from England (Stone, 1980), but has been shown to infect plants in the Netherlands (Chen et al. 2005), the United States (Jordan et al. 2008) and Japan (Nijo et al. 2018). To date, the complete genomes of two LVX isolates from the Netherlands and Japan have been reported. Paris polyphylla var. yunnanensis, known as Dianchonglou in China, is a perennial plant of the family Melanthiaceae (formerly belonging to the family Trillium). In China, its rhizome is commonly used as an antispasmodic agent for stroke and cancer treatment (Chang et al. 2017). From 2019 to 2022, leaf mottle and shrinkage which are typical symptoms of viral infections were observed on the leaves of P. polyphylla var. yunnanensis plants in Dianchonglou fields in Qujing, Yunnan. Disease incidence ranged from 19% to 45% across 5 fields (90 plants per field) in Qujing. To identify the possible viral pathogen(s) associated with the disease, the mirVanaTM miRNA isolation Kit was used to extract total RNA was from a mixed sample pool of 5 symptomatic leaf samples collected from the 5 fields. RNA sequencing library was constructed using TruSeqTM RNA sample preparation kit. Sequencing on the Illumina HiSeqTM 2500 platform (Illumina, USA) with 125-bp paired-end reads yielded 23,077,786 raw reads. 22,534,100 clean reads were obtained by removing reads of low quality and poly-N using Trimmomatic software (Bolger et al. 2014). By utilizing the paired-end splicing method in Trinity software (Grabherr et al. 2011) the the raw reads were De novo assembled into 184,596 contigs, of which 303 were related to viruses, including Paris mosaic necrosis virus (PMNV), Pear alphapartitivirus (PAPV), Dahlia mosaic virus (DMV), and Lily virus X (LVX). BLASTn analysis revealed that 12 contigs (lengths ranging from 344 nt to 5,981 nt, query cover 6% to 99%) were most similar (57.32% to 91.67% nt identities) to the genome sequences of LVX, suggesting a possible infection of LVX in the plants. To confirm the result, a full-length genomic sequence of LVX was obtained by reverse transcription polymerase chain reaction (RT-PCR) using specific primers designed based on the sequence of the assembled contigs. The PCR products were cloned into pGEM-T vector (Promega Corporation, USA) and sequenced using the Sanger method (Sangon Biotech, Shanghai, China). The obtained full-length genomic sequence of the LVX isolate (LVX-PP, accession number OM100017) was 5,981 nt in length. BLASTp analysis demonstrated that the putative Rep and CP of LVX-PP shared 76.27% to 81.05% and 80.81% to 81.82% aa sequence similarities with that of other LVX isolates, respectively. Maximum-likelihood phylogenetic trees inferred from the Rep and CP aa sequences showed that LVX-PP clustered closely with LVX isolates. The leaf samples were further analyzed using a lily virus X (LVX) ELISA kit (DEIAPV181, Creative Diagnostics, U.S.A.). Healthy P. polyphylla var. yunnanensis leaves were taken as a negative control and buffer solution as a blank control. The results showed a positive reaction for all five symptomatic plants (OD = 1.259 ± 0.007) relative to the negative (OD = 0.099) and blank (OD = 0.073) controls. These results indicate that LVX can infect P. polyphylla var. yunnanensis. To our knowledge, this is the first report that LVX has been detected in P. polyphylla var. yunnannensis. This study will serve as an important reference for the study of the host range of LVX. Further studies will be required to determine how LVX spreads between P. polyphylla var. yunnannensis and other host plants.

Sophora flower (Huaihua) is the flower of Sophora japonica L., which is used in ethnic food and traditional medicine in China. Unfortunately, the molecular mechanism related to the nutritional quality and regulation of floral organ development has yet to be elucidated in Huaihua. To understand the molecular mechanism of the different developmental stages of Huaihua, this study evaluated the transcriptome analyses of five different developmental periods from Huaihua. A total of 84,699 unigenes were reassembled from approximate 50 million high-quality clean reads. The results showed that the phenylpropanoid biosynthesis, plant hormone signal transduction, starch and sucrose metabolism, and fatty acid elongation process pathways were strongly induced at different developmental stage genes in Huaihua. During this study, 394 differentially expressed genes (DEGs) were identified for further studies, which included 13 phenylpropanoid biosynthesis-related genes, 186 plant hormone signal transduction-related genes, and 195 starch and sucrose metabolism response genes. Regarding the peroxidase in the lignin synthesis pathway, CCoAOMT was significantly upregulated with the development of Huaihua. The enzyme genes in flavonoid synthesis, such as PAL, 4CL, flavonol reductase, and 3 GT, were significantly downregulated during Huaihua development. In addition, the results also indicated that the enrichment key genes in these pathways of Huaihua can be divided into two distinct parts at developmental stages. In the floral bud stage, flavonoid, auxin, and cytokine synthesis-related genes were highly expressed. In the mature bud and full flowering stage, the expression level of genes related to lignin, gibberellin, abscisic acid, and salicylic acid synthesis was high, while, for other genes related to flavonoid synthesis, it was lower. Furthermore, the DEGs in the starch and sucrose metabolism pathway were also significantly upregulated in the later stage of flower development. This study provides a preliminary and comprehensive assessment of the quality formation and flowering regulation mechanism in Sophora japonica L. by investigating the expression profiles of the critical flowering-related genes at different developmental stages. The results indicate that the regulatory genes in these key biological pathways could be crucial factors involved in Huaihua development, which can provide a reference and new insights with which to further understand the molecular mechanisms of flower development in Sophora japonica L.

Chinese figwort (Scrophularia ningpoensis Hemsl.) is an important annual herb and its dried root tubers are used as a traditional Chinese herbal medicine. In May 2021, a disease with stem rot sympt...