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

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

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

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

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

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

A method for determintion of allantion in Psammosilene tunicoides was established by HPLC. Using alcohol as the extraction solvent, the subsequent filtrate of P. tunicoides was analysed by HPLC. Allantoin was successfully detected and separated by ZORBAX NH2 column (4.6 mm x 150 mm,5 microm) at wavelength of 220 nm and column temperature of 40 degrees C, with acetonitrile-water (93: 7) as mobile phase at a flow rate of 1.0 mL x min(-1). The results showed that it had a good linear relationship between the concent ration of allantion and chromatographic peak area. The linear correlation coefficient of allantion was 0.999 5 in 0.010 4-0.166 g x L(-1). The relative standard deviation of six parallel injections was less than 2.1%. The average recoveries were ranged from 95.47% to 100.9%. This method was sensitive and accurate for the determination of allantion in P. tunicoides.
Allantoin ; analysis ; Animals ; Caryophyllaceae ; chemistry ; Chromatography, High Pressure Liquid ; methods ; Drug Stability ; Humans ; Rats ; Reproducibility of Results

OBJECTIVESeed dormancy mechanisms, breaking dormancy and the optimal germinating conditions were studied to improve reproductive efficiency and quality standard of Pseudostellaria heterophylla.

METHODThe P. heterophylla seeds were stratified into wettish sand for 65 days under the temperature of -2-3 degrees C, embryo length and germination dynamic change of seeds were measured in prophase every other 10 days and in middle every other 5 days. The influences on seed germination and seedling growth under different temperatures, germination beds were investigated.

RESULTThe P. heterophylla seeds embryo morphology was unchanged in stratification. The seeds could not germinate at stratification within the first 35 days. The germination rate and germination energy of seeds increased with the stratification time after 35 days. Germination rate, germination energy, plant height and fresh weight under the 10 degrees C were significantly higher than those under other temperatures. Germination rate, germination energy, plant height, fresh weight and dry weight of plant in sand bed were higher than those of plant in other beds, and seed mildew rate and abnormal seedling proportion of plant in sand bed were less than those of plant in other beds.

CONCLUSIONThe dormancy of P. heterophylla seeds is mainly the physiological post-maturation. The optimal germination conditions of seeds is 10 degrees C the culture of sand. The dormancy was broke under -2-3 degrees C of wettish sand for 45-50 days in practice.

Caryophyllaceae ; growth & development ; Germination ; Light ; Plant Dormancy ; physiology ; Seeds ; physiology ; Temperature

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