The genus Peronospora, an obligate biotrophic group belonging to Oomycota, causes serious damage to a variety of wild and ornamental plants, as well as cultivated crops, such as beet, rose, spinach, and tobacco. To investigate the diversity of Peronospora species parasitic to Stellaria and Pseudostellaria (Caryophyllaceae) plants in Korea, we performed a morphological analysis on dried herbarium specimens and molecular phylogenetic inferences based on internal transcribed spacer rDNA and cox2 mitochondrial DNA sequences. As a result, it was confirmed that there are four species of Peronospora parasitic to specific species of Stellaria and Pseudostellaria, all of which were hitherto unrecorded in Korea: P. alsinearum (ex Stellaria media), P. stellariae-aquaticae (ex Stellaria aquatica), P. stellariae-uliginosae (ex Stellaria alsine), and P. pseudostellariae (ex Pseudostellaria palibiniana). In addition, Peronospora specimens parasitic to Pseudostellaria davidii differed morphologically from P. pseudostellariae owing to the large and ellipsoidal conidia; this morphological discrepancy was also validated by the high genetic divergence between the two species. Peronospora casparyi sp. nov. is described and illustrated here.
Beta vulgaris ; Caryophyllaceae ; Classification* ; DNA, Mitochondrial ; DNA, Ribosomal ; Host Specificity ; Korea* ; Oomycetes ; Peronospora* ; Phylogeny* ; Spinacia oleracea ; Spores, Fungal ; Stellaria* ; Tobacco

OBJECTIVETo study the chemical constituents of Psammosilene tunicoides.

METHODThe two chemical constituents were separated by various chromatographic methods, and their structures were identified on the basis of spectroscopic analysis.

RESULTTwo beta-carboline alkaloids were separated from normal butanol fraction of P. tunicoides, and identified as 1-acetyl-3-methoxycarbonyl-beta-carboline (1) and 1-acetyl-3-methoxycarbonyl-4-hydroxyl-beta-carboline (2).

CONCLUSIONCompound 1 is separated from this plant as natural products for the first time, and compound 2 was a new compound.

Alkaloids ; analysis ; Carbolines ; analysis ; Caryophyllaceae ; chemistry

Violet root rot is one of the main root diseases in the production process of Pseudostellaria heterophylla. To clarify the pathogenic species that cause the violet root rot of P. heterophylla in Fujian province, the roots and the sclerotia with violet root rot symptoms were collected from the main producing areas of P. heterophylla(Fujian province) from 2017 to 2021, and the pathogens were isolated by tissue separation method and identified by morphology and multi-gene phylogenetic analysis. Additionally, the biological characteristics of the pathogens were studied and the fungicides were determined. The results showed that 78 strains of violet root rot were isolated from the collected root samples, which belonged to one type after preliminary morphological identification. Two represen-tative strains were selected from the pathogens for multi-gene phylogenetic analysis, and they were clustered with Helicobasidium mompa together. The suitable culture conditions for the mycelium were OA medium, 25 ℃, pH 6, and ammonium oxalate as the nitrogen source. The lethal temperature of the mycelium was 50 ℃ for 10 minutes. Moreover, 99.1% propiconazole and 98.7% azoxystrobin had the optimal bacteriostatic effect, and the concentrations with the 50% bacteriostatic rate were 16.85 and 12.24 μg·mL~(-1), respectively. On the basis of the above results, the pathogen causing violet root rot of P. heterophylla in Fujian province was H. mompa. The medium type, growth temperature, pH value, nitrogen source, etc. had significant effect on the growth of mycelium.
Plant Roots ; Phylogeny ; Temperature ; Caryophyllaceae ; Nitrogen

In Zherong county, Fujian province, the black spot of Pseudostellaria heterophylla often breaks out in the rainy season from April to June every year. As one of the main leaf diseases of P. heterophylla, black spot seriously affects the yield and quality of the medicinal material. To identify and characterize the pathogens causing black spot, we isolated the pathogens, identified them as a species of Alternaria according to Koch's postulates, and then tested their pathogenicity and biological characteristics. The results showed that the pathogens causing P. heterophylla black spot were A. gaisen, as evidenced by the similar colony morphology, spore characteristics, sporulation phenotype, and the same clade with A. gaisen on the phylogenetic tree(the maximum likelihood support rate of 100% and the Bayesian posterior probability of 1.00) built based on the tandem sequences of ITS, tef1, gapdh, endoPG, Alta1, OPA10-2, and KOG1077. The optimum conditions for mycelial growth of the pathogen were 25 ℃, pH 5-8, and 24 h dark culture. The lethal conditions for mycelia and spores were both treatment at 50 ℃ for 10 min. We reported for the first time the A. gaisen-caused black spot of P. heterophylla. The results could provide a theoretical basis for the diagnosis and control of P. heterophylla leaf spot diseases.
Bayes Theorem ; Phylogeny ; Caryophyllaceae ; Alternaria ; Mycelium

OBJECTIVETo provide new germplasm materials for breeding new varieties of Pseudostellaria heterophylla.

METHODThe method of single plant selection was adopted, with the comparative experiments being carried out under the same conditions in Shibing county. The 8 plants of Shibing SB-4 were compared respectively with factor analysis for 27 phenotypic traits and 8 yield traits, and single factor variance analysis for the contents of polysaccharides.

RESULTUsing factor analysis, 27 phenotypic traits were classified into 7 principal divisors and 8 yield traits were simplified into 3 principal divisors. The 4 strains of P. heterophylla, ZT-01, ZT-02, ZT-06 and ZT-07, performed better than others in the phenotypic traits, and ZT-01, ZT-02, ZT-03 and ZT-07 in the yield traits. The contents of polysaccharides of ZT-01, ZT-02, ZT-05 and ZT-08 showed significantly higher value.

CONCLUSIONThere is significant difference among the 8 strains of P. heterophylla in phenotypic traits, yield traits and quality traits, making it possible to select certain strains for different purposes. ZT-01 and ZT-02 can be breaded further. ZT-06 and ZT-07 were used as ornamental cultivars for its great phenotypic traits. ZT-03 with good resistance and high yield was taken as resistant variety, and ZT-05 would face next selection on the basis of its high content of polysaccharide.

Breeding ; Caryophyllaceae ; chemistry ; growth & development ; China ; Phenotype ; Polysaccharides ; analysis

Fusarium is the major pathogen of root rot of Pseudostellaria heterophylla. This study aims to explain the possible distribution of Fusarium species and the contamination of its toxin-chemotypes in tuberous root of P. heterophylla. A total of 89 strains of fungi were isolated from the tuberous root of P. heterophylla. Among them, 29 strains were identified as Fusarium by ITS2 sequence, accounting for 32.5%. They were identified as five species of F. avenaceum, F. tricinctum, F. fujikuroi, F. oxysporum, and F. graminearum based on β-Tubulin and EF-1α genes. LC-MS/MS detected 18, 1, and 5 strains able to produce ZEN, DON, and T2, which accounted for 62.1%, 3.4%, and 17.2%, respectively. Strain JK3-3 can produce ZEN, DON, and T2, while strains BH1-4-1, BH6-5, and BH16-2 can produce ZEN and T2. PCR detected six key synthase genes of Tri1, Tri7, Tri8, Tri13, PKS14, and PKS13 in strain JK3-3, which synthesized three toxins of ZEN, DON, and T2. Four key synthase genes of Tri8, Tri13, PKS14, and PKS13 were detected in strains BH1-4-1, BH6-5, and BH16-2, which were responsible for the synthesis of ZEN and T2. The results showed that the key genes of toxin biosynthesis were highly correlated with the toxins produced by Fusarium, and the biosynthesis of toxin was strictly controlled by the genetic information of the strain. This study provides a data basis for the targeted prevention and control of exo-genous mycotoxins in P. heterophylla and a possibility for the development of PCR for rapid detection of toxin contamination.
Caryophyllaceae ; Chromatography, Liquid ; Fusarium/genetics* ; Mycotoxins ; Tandem Mass Spectrometry

Pseudostellaria heterophylla in large-scale cultivation needs to apply pesticides to control diseases, and non-standard use of pesticide may cause excessive pesticide residues in medicinal materials, increasing the risk of clinical medication. To accurately monitor the residual pesticides, this paper investigated the drug use during the process of P. heterophylla disease prevention in 25 P. he-terophylla planting enterprises or individual households in Guizhou province. It was found that there were 8 common diseases in P. he-terophylla planting, including leaf spot, downy mildew, virus disease, root rot, dropping disease, purple feather disease, white silk disease, and damping-off disease. Twenty-three kinds of pesticides were used in disease control, mainly chemical synthetic pesticides, accounting for 78.3%, followed by biological pesticides and mineral pesticides, accounting for 13.0% and 8.7%, respectively. The disease prevention and control drugs were all low-toxic pesticides, and there were no varieties banned in the Chinese Pharmacopoeia(2020 edition). However, the pesticides used have not been registered on P. heterophylla, and the excessive use of drugs was serious. The present monitoring of pesticide residues in P. heterophylla is mainly based on traditional pesticides such as organochlorine, organophosphorus, and carbamate, which does not effectively cover the production of drugs and had certain safety risks. It is suggested to speed up the research and registration of drug use in the production of P. heterophylla, increase the use of biological pesticides, and further improve the monitoring indicators of pesticide residues in combination with the actual production of drugs, so as to promote the high-quality development of P. heterophylla industry.
Biological Control Agents ; Caryophyllaceae ; Pesticide Residues ; Pesticides ; Plants, Medicinal

OBJECTIVETo establish a culture system for Psammosilene tunicoides hairy roots, and provide technological aid for the large-scale production of P. tunicoides material.

METHODThe young leaves and stem segments of sterile plantlets were infected with ACCC10060 strain, and subsequently a culture system suitable for hairy roots growth was further established.

RESULTWhen explants were co-cultured with ACCC10060 (A600 0.8) on B5 media containing 20 mg x L(-1) Acetosyringo (AS) for 48 h, the hairy roots could be successfully induced, and it could achieve a higher induction rate using young leaves as explants than that of stem segments. The transfected hairy roots possessed the ability of kanamycin resistance and growth on hormone-free media, and synthesis of opines. All above results demonstrated that the present hairy roots originated in the infection of P. tunicoides tissues by ACCC10060 strains. After 35 d culture in liquid hormone-free MS (1/2 strength), the biomass of hairy roots increased 14.11 times (fresh weight) and 8. 39 times (dry weight), respectively, and the content of total saponins in hairy roots reached to 0.857% (DW), by contrast, it's only 0.388% and 0.217% in callus and seedlings respectively.

CONCLUSIONEstablishment of hairy roots culture of P. tunicoides provided a foundation for industrial production of active components from P. tunicoides culture.

Biomass ; Caryophyllaceae ; growth & development ; microbiology ; Culture Techniques ; Plant Roots ; growth & development ; microbiology ; Rhizobium ; physiology ; Saponins ; analysis

OBJECTIVETo study the chemical constituents of the cultivated Pseudostellaria heterophylla (Zheshen No. 1) as a traditional Chinese medicine, and provide a scientific basis for its quality evaluation.

METHODThe chemical constituents were isolated by silica gel column chromatography and structurally elucidated by analysis of their physicochemical characteristics including spectroscopic data.

RESULTThirteen compounds were obtained and identified as taraxeryl acetate (1), taraxerol (2), stigmast-7-en-3beta-ol(3), beta-sitosterol (4), daucosterol (5), stigmast-7-en-3-O-beta-D-glucopyranoside (6), dihydroferulic acid [3-(4-hydroxy-3-methoxyphenyl) propionic acid] (7), adenosine (8), uridine (9), alpha-ethyl-D-galactopyranoside (10), 3-furfuryl pyrole-2-carboxylate (11), glucose (12), and sucrose (13), respectively.

CONCLUSIONCompounds 1, 2 and 7-10 were isolated from the root tuber of P. heterophylla for the first time.

Caryophyllaceae ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Magnetic Resonance Spectroscopy ; Plant Tubers ; chemistry ; Spectrometry, Mass, Electrospray Ionization

OBJECTIVETo develop an effective identification method for accurately discriminating Psammosilene tunicoides and its confused species by the combined method of microscopic identification and molecular identification, so-called systematic identification of Chinese materia medica (SICMM).

METHODP. tunicoides and its confused species were accurately discriminated by SICMM method, which was established by comprehensively use of microscopic identification and DNA identification method. The DNA identification included the following analysis: the BLAST alignment, specific bases and N-J phylogenetic tree analysis.

RESULTThe cluster crystals were not observed in P. tunicoides, but great deals of them were found in Silene viscidula. Further more, big differences of ITS sequence were observed and analyzed between P. tunicoides and its confused specie of S. viscidula.

CONCLUSIONThe system method is a scientific and accurate method for the identification of P. tunicoides and its counterfeit species.

Base Sequence ; Caryophyllaceae ; chemistry ; classification ; cytology ; genetics ; DNA, Intergenic ; Phenotype ; Phylogeny ; Sequence Alignment