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.

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.

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.

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.

Morphological comparison of glandular and non-glandular trichomes between Artemisia stolonifera and A. argyi / 中国中药杂志

The basic features of glandular and non-glandular trichomes on leaves of Artemisia argyi( germplasms from Qichun,Ningbo,Tangyin,and Anguo,respectively) and related species A. stolonifera were observed by scanning electron microscopy( SEM)and compared. There were significant differences in trichome characteristics of leaves at all parts of A. argyi and A. stolonifera,which were closely related to the difference in chemical components. The length of non-glandular trichomes and size of glandular trichomes on middle leaves were the stablest. A. argyi and A. stolonifera can be distinguished by the density of glandular trichome. Additionally,the four germplasms of A. argyi can be discriminated via the density and curvature of non-glandular trichome. The density of non-glandular trichomes was the highest in A. stolonifera. For A. argyi,the germplasm from Qichun had the highest density of non-glandular trichomes on the abaxial surfaces of upper leaves and that from Ningbo had the largest non-glandular trichome curvature. With regard to the germplasm from Anguo,the T-shaped non-glandular trichomes of long stalks on the adaxial surfaces of the middle leaves were lodging-susceptible,and those with slender heads were wave-like. Statistics results of A. argyi and A. stolonifera are as follows: largest glandular trichomes on the adaxial and abaxial surfaces and highest glandular trichome density on the abaxial surfaces of the lower leaves in A. argyi germplasm from Ningbo,highest density of non-glandular trichomes on the abaxial surfaces of upper leaves in A. stolonifera,and highest density of glandular trichomes and non-glandular trichomes on the adaxial surfaces of the upper leaves in A. argyi germplasm from Qichun. According to the observation result under fluorescence microscope( FM),flavonoids were closely related to the size and density of non-glandular trichomes and size of glandular trichomes. The fluorescence intensity was the strongest and fluorescence area was the largest for flavonoids in A. argyi germplasms from Qichun and Tangyin,while the fluorescence for flavonoids was the weakest in A. stolonifera. It was the first time to observe and analyze the trichome ultrastructure of A. argyi leaves at different positions by SEM and FM. This study clarifies the differences between A. stolonifera and four famous A. argyi germplasms,which provides new evidence for the microscopic identification of A. argyi and its related species and serves as a reference for the study of the relationship of A. argyi structure with its components and functions.

Analysis and evaluation of volatile oil content in leaves of different Artemisia argyi germplasm resources / 中国中药杂志

Volatile oil is the main effective component and an important quality indicator of Artemisia argyi leaves. In this study, 100 germplasm resources of A. argyi were collected from all the related habitats in China. The total volatile oils in A. argyi leaves were extracted by steam distillation and the content was determined by GC-MS. The result demonstrated that the content of total volatile oils was in the range of 0.53%-2.55%, with the average of 1.43%. A total of 39 chemical constituents were identified from the volatile oils, including 13 shared by the 100 germplasm resources. Clustering analysis of the 39 constituents showed that the 100 A. argyi samples were categorized into groups Ⅰ(9), Ⅱ(2), Ⅲ(66) and Ⅳ(23), and group Ⅲ had the most volatile medicinal components, with the highest content. Five principal components(PCs) were extracted from 13 shared constituents, which explained 73.454% of the total variance. PC1, PC2, and PC3 mainly reflected the pharmacological activity of volatile oils and the rest two the aroma information. The volatile oils identified in this study lay a foundation for variety breeding of and rational utilization of volatile oils in A. argyi leaves.

[Effects of different planting density, leaf position and leaf age on growth and quality of Artemisia argyi var. argyi 'Qiai'].

In order to guide the standardized planting and scientific harvesting of Artemisia argyi var. argyi 'Qiai', effects of diffe-rent planting density, leaf position and leaf age on the growth and quality of A. argyi var. argyi 'Qiai' were studied in this paper. The results showed that appropriate sparse planting could increase stem diameter, compact leaf spacing, increase the leaf size, reduce the rate of withered leaves and increase the number of effective leaves. Dense planting can significantly increase the yield of A. argyi var. argyi 'Qiai' per Mu(1 Mu≈667 m~2) and the output rate of moxa, but reduce the yield per plant and the number of effective leaves. With the decrease of leaf position and the increase of leaf age, the leaf size and the weight of one hundred leaves increased at first and then decreased, the density of non-glandular hair field of the lower epidermis and the output rate of moxa decreased. With the increase of planting density, the contents of eucalyptus oleoresin, camphor, α-platyclone, and cyanidin decreased gradually, the contents of chlorogenic acid, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C in the leaves of A. argyi var. argyi 'Qiai' increased gradually, while the contents of borneol, bornyl acetate and isozelanin increased at first and then decreased significantly. With the decrease of leaf position and the increase of leaf age, the contents of volatile oil, phenolic acid and flavonoid in A. argyi var. argyi 'Qiai' decreased gradually. PCA analysis can divide the leaf quality characteristics of A. argyi var. argyi 'Qiai' into two parts: the middle and upper 10-30 days leaf age, the middle and lower 40-50 days above leaf age. Based on the above factors, the planting density of 28 000 plants/Mu(row spacing of 10 cm×20 cm) can be selected for cultivation of A. argyi var. argyi 'Qiai' rhizome, and the effective plants in the field are about 142 800 plants/Mu. In terms of harvesting, it is suggested that the A. argyi var. argyi 'Qiai' should be harvested on "March 3 rd" and "May 5 th" of the lunar calendar. If it is the traditionally harvested at one time in May, the A. argyi var. argyi 'Qiai' should be divided into two parts: the middle and upper leaves, the middle and lower leaves, so as to achieve high quality and high price of A. argyi var. argyi 'Qiai' leaves and improve the economic benefits of A. argyi var. argyi 'Qiai' planting.

[Moxa nitrogen content determination and its application in moxa floss grade identification].

Artemisia argyi samples were collected from different areas in Hubei Qichun and medicinal botanical garden of Hubei University of Traditional Chinese Medicine, and samples were purchased from different areas in Qichun medicinal market. The same method was used to prepare A. argyi samples from different areas into moxa floss of different leaf velvet ratio. The nitrogen content of A. argyi was determined by Kjeldahl method. The results show that there was an inverse relationship between the content of nitrogen and the level of the leaf velvet ratio grades of moxa floss and nitrogen content. Therefore, six functional models were established to illustrate the relationship between the grades of leaf velvet ratio and nitrogen content. The accuracy of the functional models was evaluated by ■. The cubic function model and exponential function model are selected as the best models and the formula is: Y_(grades)=-4.26 N~3+26.09 N~2-61.09 N+55.84, Y_(grades)=63.68×10~(-1.374N), with R~2 values of 0.976 5 and 0.969 6, respectively. The accuracy reached above 95% of the two function models when verified by laboratory-made moxa floss, while the accuracy of the models was 85.44% when verifed by commercial moxa floss. These results indicate that the model could be applied to the identification of the grades of moxa floss.

[Effect of planting period and ridge pattern on yield and quality of Artemisia argyi var.argyi 'Qiai'].

To solve the problems of the unclear planting period and the traditional flat planting of Artemisia argyi var.argyi 'Qiai', such as the serious dead leaves in the middle and lower parts of the plant and the low yield and low quality in the field, the effects of different planting period and ridge pattern on yield and quality of A. argyi var.argyi 'Qiai' were studied. The results showed that the growth and development of A. argyi var.argyi 'Qiai' was better when planted in autumn and winter, and the ridge directions had little effect on the growth and yield of A. argyi var.argyi 'Qiai', while the ridge width had a significant effect. Compared the traditional wide ridge planting mode(the width of the ridge is 160 cm) with the ridge width of 80 cm, 60 cm and 40 cm, the results showed that the density per unit area, the number of effective plants, and the rate of dead leaves were decreased, while the number of productive leaves per plant, the number of lateral branches, and the total yield per plant were increased, the total yield was decreased. The output rates of moxa in the leaves of A. argyi var.argyi 'Qiai' decreased with the planting time postponed and the width of planting ridge increased. The contents of volatile oil, 1,8-oxido-p-menthane, camphor and borneol in A. argyi var.argyi 'Qiai' reach to the highest when planted in autumn and winter and the ridge width was 80 cm. In addition, the contents of total flavonoids, kaempferol, jeceosidin and eupatilin flavonoids in the leaves of A. argyi var.argyi 'Qiai' gradually decreased as the planting period postponed and the ridge width increased. The results show that the A. argyi var.argyi 'Qiai' should be planted in autumn and winter, and the double row ridge planting mode with width of 60-80 cm is more suitable for the cultivation and production of A. argyi var.argyi 'Qiai' in Qichun County of Hubei Province. This study will provide a theoretical basis and guidance for higher yield and quality in cultivation of A. argyi var.argyi 'Qiai' in Qichun county.