Identification and expression analysis of flavonoid O-methyltransferases gene family in Artemisia argyi / 药学学报

italic>Artemisia argyi (A. argyi) is a Chinese herbal medicine in China. The main active components are volatile oils, flavonoids, and other compounds, which have various pharmacological activities. Methoxylated flavonoids are the main active ingredients in A. argyi. Flavonoid O-methyltransferase (FOMT) is a key enzyme in the O-methylation of flavonoids. In order to further understand the function and characteristics of FOMT proteins, this paper carried out the whole genome mining and identification of FOMT genes in A. argyi and performed phylogenetic, chromosomal localization, gene sequence characterization, subcellular localization prediction, protein structure, gene structure analysis, and expression pattern analysis. The results showed that a total of 83 FOMT genes were identified in the genome of A. argyi. The phylogenetic tree shows that FOMT genes are divided into two subgroups, CCoAOMT (caffeoyl CoA O-methyltransferase) subfamily (32 genes) and COMT (caffeic acid O-methyltransferase) subfamily (51 genes). Gene sequence analysis showed that the number of amino acids encoded by FOMT was 70-734 aa, the molecular weight was 25 296.55-34 241.3 Da, and the isoelectric point was 4.51-9.99. Compared with 32 members of the CCoAOMT subfamily, nearly 1/3 of the 51 members of the COMT subfamily were hydrophobic proteins and 2/3 were hydrophilic proteins. Subcellular localization prediction showed that more than 80% of CCoAOMT subfamily members were located in the cytoplasm, and 96% of COMT subfamily members were located in the chloroplast. COMT subfamily members have more motifs than CCoAOMT subfamily members. The N-terminal motifs of COMT subfamily proteins are relatively variable, while the C-terminal motifs are relatively conserved. Expression pattern analysis showed that CCoAOMT subfamily members were mainly expressed in roots, while COMT members were mainly expressed in leaves. Some FOMTs showed the tissue expression specificity by real-time quantitative PCR analysis, especially in leaves. In this study, we identified and analyzed the FOMT gene family in A. argyi, and provided a theoretical basis for further research on the function of FOMTs and the biosynthesis of methylated flavonoids in A. argyi.

Distinguishing between Artemisia stolonifera and A. argyi by specific PCR of leaves and non-glandular trichomes / 中国中药杂志

Artemisia stolonifera is a relative of A. argyi. The two species are difficult to be distinguished due to the similarity in leaf shape and have even less distinctive features after processing. This study aims to establish a method to quickly distinguish between them. At the same time, we examined the reasonability and applicability of the specific polymerase chain reaction(PCR) method. The C/T single nucleotide polymorphism was detected at the position 202 of the sequence, based on which specific primers were designed to identify these two species. The PCR with the specific primer JNC-F and the universal primer ITS3R produced a specific band at 218 bp for A. argyi and no band for A. stolonifera, which can be used to detect at least 3% of A. argyi samples mixed in A. stolonifera samples. The PCR with the specific primer KY-F and the universal primer ITS3R produced a specific band at 218 bp for A. stolonifera and no band for A. argyi, which can be used to detect at least 5% of A. stolonifera samples mixed with A. argyi. The limit of detection of the established method was 5 ng DNA. The established PCR method can accurately distinguish between A. stolonifera and A. argyi, which provides an experimental basis for the quality control of A. stolonifera and determines whether the herbs are adulterated.

Corythucha marmorata affects growth and quality of Artemisia argyi / 中国中药杂志

This study aims to investigate the impact of the invasive pest Corythucha marmorata on the growth and quality of Artemi-sia argyi. The signs of insect damage at the cultivation base of A. argyi in Huanggang, Hubei were observed. The pests were identified based on morphological and molecular evidence. The pest occurrence pattern and damage mechanism were investigated. Electron microscopy, gas chromatography-mass spectrometry(GC-MS), and high performance liquid chromatography(HPLC) were employed to analyze the microstructure, volatile oils, and flavonoid content of the pest-infested leaves. C. marmorata can cause destructive damage to A. argyi. Small decoloring spots appeared on the leaf surface at the initial stage of infestation. As the damage progressed, the spots spread along the leaf veins and aggregated into patches, causing yellowish leaves and even brownish yellow in the severely affected areas. The insect frequently appeared in summer because it thrives in hot dry conditions. After occurrence on the leaves, microscopic examination revealed that the front of the leaves gradually developed decoloring spots, with black oily stains formed by the black excrement attaching to the glandular hairs. The leaf flesh was also severely damaged, and the non-glandular hairs were broken, disor-ganized, and sticky. The content of neochlorogenic acid, cryptochlorogenic acid, isochlorogenic acids A and B, hispidulin, jaceosidin, and eupatilin at the early stage of infestation was significantly higher than that at the middle stage, and the content decreased at the last stage of infestation. The content of eucalyptol, borneol, terpinyl, and caryophyllin decreased in the moderately damaged leaves and increased in the severely damaged leaves. C. marmorata was discovered for the first time on A. argyi leaves in this study, and its prevention and control deserves special attention. The germplasm materials resistant to this pest can be used to breed C. marmorata-resis-tant A. argyi varieties.

Prediction analysis of quality markers and resource evaluation of Artemisiae Argyi Folium based on chemical composition and network pharmacology / 中国中药杂志

This study is based on ultra-high-performance liquid chromatography(UPLC), gas chromatography-mass spectrometry(GC-MS), and network pharmacology methods to analyze and predict potential quality markers(Q-markers) of Artemisiae Argyi Folium. First, UPLC and GC-MS techniques were used to analyze the content of 12 non-volatile components and 8 volatile components in the leaves of 33 Artemisia argyi germplasm resources as candidate Q-markers. Subsequently, network pharmacology was employed to construct a "component-target-pathway-efficacy" network to screen out core Q-markers, and the biological activity of the markers was validated using molecular docking. Finally, cluster analysis and principal component analysis were performed on the content of Q-markers in the 33 A. argyi germplasm resources. The results showed that 18 candidate components, 60 targets, and 185 relationships were identified, which were associated with 72 pathways related to the treatment of 11 diseases and exhibited 5 other effects. Based on the combination of freedom and component specificity, six components, including eupatilin, cineole, β-caryophyllene, dinatin, jaceosidin, and caryophyllene oxide were selected as potential Q-markers for Artemisiae Argyi Folium. According to the content of these six markers, cluster analysis divided the 33 A. argyi germplasm resources into three groups, and principal component analysis identified S14 as having the highest overall quality. This study provides a reference for exploring Q-markers of Artemisiae Argyi Folium, establishing a quality evaluation system, further studying its pharmacological mechanisms, and breeding new varieties.

Content of mineral elements in different Artemisia argyi germplasms and their relationship with quality properties / 中国中药杂志

To clarify the content characteristics of mineral elements in different Artemisia argyi germplasm resources and their relationship with the quality properties of Artemisiae Argyi Folium, this study measured the content of 10 mineral elements including nitrogen(N), phosphorus(P), potassium(K), calcium(Ca), magnesium(Mg), aluminum(Al), manganese(Mn), iron(Fe), copper(Cu), and zinc(Zn) in 100 Artemisia argyi germplasm samples. Besides, their relationship with the quality properties of Artemisiae Argyi Folium was explored by correlation analysis, path analysis, and cluster analysis. The results demonstrated that the variation coefficient of the 10 mineral elements in Artemisiae Argyi Folium ranged from 12.23% to 64.38%, and the genetic diversity index from 0.97 to 3.09. The genetic diversities of N, P, and Zn were obvious. As revealed by the correlation analysis, N, P, and K showed strong positive correlations with each other. Except that Mg and Al were negatively correlated, Ca, Mg, Al, Mn, Fe, Cu, and Zn were positively correlated. The correlation analysis of mineral elements with the quality properties of Artemisiae Argyi Folium proved the significant correlations of 17 pairs of characters. According to the path analysis, P, K, Ca, and Mn greatly affected the yield of Artemisiae Argyi Folium, P, K, and Mg the output rate of moxa, N, P, and K the content of total volatile oil, P and K the content of eucalyptol, and P, K, and Ca the content of eupatilin. The 100 germplasm samples were clustered into three groups. Specifically, in cluster Ⅰ, the enrichment capacity of P, K, and Mg elements was strong, and the comprehensive properties of mineral elements were better, implying good development potential. Ca, Mn, Fe, and Zn elements in cluster Ⅱ and N and Al in cluster Ⅲ displayed strong enrichment capacities. This study has provided new ideas for resource evaluation and variety breeding of A. argyi and also reference for fertilizer application.

Identification, biological characteristics, and fungicide screening of pathogen of black spot in Aconitum carmichaelii / 中国中药杂志

In Hezhang county, Guizhou province, black spot tends to occur to Aconitum carmichaelii in the hot rainy summer, with the incidence up to 50%-70%, seriously impacting the yield and quality of the medicinal material. Thus, this study aims to clarify the pathogen and the occurrence characteristics. To be specific, the pathogen was isolated and identified according to Koch's postulates and the pathogenicity and biological characteristics were determined. In addition, the sensitivity of the pathogen to four microbial fungicides, four botanical fungicides, and five chemical fungicides was determined with the mycelium growth rate method for the purpose of screening out optimal fungicides. The pathogen was identified as Alternaria alternate, as evidenced by the similar colony morphology and microscopic characteristics and 99.55%-100% similarity in sequences of rDNA-ITS, LSU, 18S, and TEF of the two. The optimum growth conditions for A. alternata were 28 ℃, pH 8, and continuous darkness. Bacillus subtilis had strong inhibitory effect on the pathogen, and the inhibition rate was more than 90% when the concentration was 1 mg·L~(-1). In addition, difenoconazole and quinoline copper can also control the pathogen, with median effective concentration(EC_(50)) of 2.92 and 9.02 mg·L~(-1), respectively. This study lays a theoretical basis for the field control of black spot in A. carmichaelii.

Fusarium Wilt Changes Microbial Community Structure in Rhizosphere Soil of Chrysanthemum morifolium / 中国实验方剂学杂志

Objective:To explore the differences in rhizosphere microbial community structure between <italic>Fusarium</italic> wilt-infected and healthy <italic>Chrysanthemum morifolium </italic>plants<italic>.</italic> Method:The rhizosphere soils of diseased and healthy<italic> C. morifolium </italic>plants were sampled and subjected to high-throughput 16S ribosomal DNA （rDNA） and internal transcribed spacer （ITS） sequencing， to identify the microbial community structure including bacteria and fungi. Result:<italic>Fusarium</italic> wilt reduced the bacterial abundance and diversity but had no significant effect on fungal alpha-diversity.The proportions of Acidobacteria， Gemmatimonadetes， and Nitrospirae in rhizosphere soil of healthy <italic>C.morifolium</italic> plants were higher than those of diseased plants， while the proportions of Proteobacteria and Bacteroidetes were lower（<italic>P</italic><0.05）. <italic>Fusarium</italic> fungi accounted for 27.49%， 14.53%， and 11.94% in diseased plants whereas 0.47%， 1.01%， and 0.67% in healthy plants.Pathogenic bacteria <italic>Pectobacterium</italic> and <italic>Dickeya</italic> were enriched in rhizosphere soil of diseased plants. The abundances of nitrifying， detoxifying， and photosynthetic bacteria in rhizosphere soil of healthy plants were higher than those of diseased plants. Conclusion:<italic>Fusarium</italic> wilt reduces the bacterial richness and diversity and triggers the enrichment of massive <italic>Fusarium</italic> fungi， <italic>Pectobacterium</italic>， and <italic>Dickeya</italic>. The proportion of beneficial bacteria in rhizosphere soil of healthy plants is significantly higher than that of diseased plants.

Analysis and Evaluation on Leaf Quality of Different Artemisia argyi Germplasm Resources / 中国实验方剂学杂志

Objective:To analyze the quality differences among different germplasm resources of <italic>Artemisia argyi </italic>and to screen out the specific germplasm by comprehensively evaluating 14 quality traits of 100 germplasm resources. Method:Germplasm resources of <italic>A. argyi </italic>were collected from all over the country. The output rate of moxa and the content of total volatile oil in <italic>A. argyi</italic> leaves were determined，and the contents of 12 flavonoids and phenolic acids in<italic> A. argyi </italic>leaves were detected by ultra performance liquid chromatography（UPLC）. The correlation analysis，principal component analysis and clustering analysis were used to comprehensively evaluate the quality of <italic>A. argyi</italic>. Result:There was rich genetic diversity of<italic> A. argyi</italic> germplasm resources，and the variation coefficients of 14 quality traits ranged from 25.67% to 127.34%，among which the coefficient of variation of chlorogenic acid，cryptochlorogenic acid，isoxiafotaside，isochlorogenic acid B and isochlorogenic acid A was more than 70%，with high variation. The output rate of moxa was negatively correlated with 9 quality traits，while the content of total volatile oil was positively correlated with 10 quality traits，and most of the flavonoids and phenolic acids had synergistic effects. 12 flavonoids and phenolic acids were analyzed by principal component analysis，and 4 principal components could be extracted. The highest contents of flavonoids and phenolic acids were found in S98（Hangzhou，Zhejiang province），S84（Longhui county，Shaoyang city，Hunan province），S66（Futian river town，Macheng city，Hubei province），S35 （Balihu town，Qichun county，Huanggang city，Hubei province），and S15 （Fudao town，Tangyin county，Anyang city，Henan province）. The systematic clustering analysis showed that the 100 germplasm could be divided into four groups when the euclidean distance was 8.0，with 90，3，3，3 and 4 accessions in group Ⅰ，Ⅱ，Ⅲ and Ⅳ，respectively. The germplasm resources in group Ⅱ contained the highest content of flavonoids and phenolic acids，the group Ⅲ contained the highest content of total volatile oil and the group Ⅳ contained the highest output rate of moxa. Conclusion:The leaf quality of different <italic>A. argyi </italic>germplasms is different. This study can provide the basis for the quality evaluation and variety breeding of <italic>A. argyi</italic> germplasm resources.

Diversity of Artemisia argyi germplasm resources based on agronomic and leaf phenotypic traits / 中国中药杂志

In this study, in order to evaluate the phenotypic diversity of Artemisia argyi germplasm resources and improve its efficiency of cultivation and breeding, 100 accessions of A. argyi germplasm resources from 58 regions in China were collected, 20 agronomic traits and leaf phenotypic traits were observed and described. The data were used for phenotypic diversity analysis, correlation analysis, principal component analysis and cluster analysis. The result showed that the genetic diversity index of 20 traits ranged from 0.82 to 4.37, among which the largest was the base depth and the smallest was the leaf width; the coefficient of variation of the 12 quantitative traits ranged from 10.55% to 41.47%. the highest coefficient of variation was the height of dead leaves, and the smallest was the content of chlorophyll, except for the angle of branches, all the quantitative characters tended to be normal distribution. The correlation analysis showed that 28 pairs of traits had significant correlation(P<0.01), and 13 pairs had significant correlation(P<0.05). According to principal component analysis, 20 traits were simplified into 9 principal components, and the cumulative contribution rate was 73.414%, nine traits including plant height, dead leaves heigh, stem diameter, symmetry of leave base, stipule, leaf tip shape, depth of the first pair of lobes, depth of the second pair of lobes and leaf yield were selected as key indexes for evaluating agronomic traits and leaf phenotypic traits of A.argyi germplasm resources. With cluster analysis, 100 accessions of A.argyi were classified into 3 groups, the groupⅠincluded the dwarf plants with thick stem and large leaf, the groupⅡincluded high plants with wide leaf and high yield, the group Ⅲ included dwarf plants with thin stem and flat bottom shape of leaf, which could provide the basis for cultivation identification and variety breeding of A.argyi germplasm resources.

Identification,biological characteristics and fungicide screening of pathogen of southern blight in Cynanchum stauntonii / 中国中药杂志

During the high-temperature and rainy season from June to October in 2017-2019,serious southern blight broke out in the Cynanchum stauntonii planting area in Tuanfeng county,Hubei province,which had a great impact on the yield and quality of medicinal materials. In this study,the pathogen of C. stauntonii was isolated,purified,and identified,and the pathogenicity was tested according to Koch's postulates. Meanwhile,the biological characteristics of the pathogen were analyzed. On this basis,the effective fungicides were screened in laboratory. Finally,the pathogen( BQ-1) was identified as Athelia rolfsii( Deuteromycotina,Basidiomycota,anamorph: Sclerotium rolfsii). The optimum growth conditions for BQ-1 were 25-30 ℃,p H 5-8,and alternating light and dark.The effective chemical fungicides were lime-sulphur-synthelic-solution( LSSS) and flusilazole,and the effective botanical fungicide was osthole. BQ-1 was highly homologous to the pathogen HS-1 of peanut southern blight,with the similarity of 18 S r DNA and TEF sequences at 99. 09%. The southern blight in C. stauntonii might be resulted from that in peanut. In the production of C. stauntonii,the following measures should be taken: avoiding rotation or neighboring with peanut,draining water from June to October to reduce humidity,and reasonably applying fungicides.