First Report of Epicoccum sorghinum Causing Leaf Spot on Paeonia suffruticosa in China.

Tree peony (Paeonia suffruticosa Andr.; Paeoniaceae) is highly valued in Chinese culture for their ornamental and medicinal benefits in anti-inflammation, anti-arrhythmia, activating the immune system and protecting the cardiovascular system (Zhai et al. 2020). In May from 2019 to 2021, leaf spot symptoms were observed on tree peony in an area of 0.8 hm2 in Bozhou, Anhui Province, China; with a disease incidence of 35%. Initially, black-brown spots (0.5-2.4 mm) appeared on the leaves, as the disease developed, the spots enlarged to form round, black lesions. Small pieces of tissue taken from the margins of lesions were surface-disinfected by 75% ethanol for 20 s followed by 0.1% mercuric chloride for 3 min, rinsed with distilled sterile water for three times, placed on potato dextrose agar (PDA) at 25 ºC for 7 days in the dark.Fifteen single spore isolates were obtained as described (Dong 2009). When cultured on PDA for 10 days, colonies were white, villose, then became gray-brown, with the reverse side becoming reddish-brown; Chlamydospores globose or irregular shaped, dark brown, unicellular or multicellular (4.3 to 12.2 × 13.1 to 33.7 µm) (n = 200). Pycnidia were black-brown, mostly spheroid, and 86 to 128 × 110 to 197 µm (n = 50); Conidia were hyaline, ellipsoidal, unicellular, aseptate, and 4.1 to 5.2 × 1.8 to 2.4 µm (n = 200) . The DNA of a representative isolate AF21-1-2 was extracted using the CTAB protocol (Doyle and Doyle 1987). The rDNA internal transcribed spacer (ITS), ß-tubulin (TUB) and 28s nrDNA (LSU) genes were amplified and sequenced using the primers ITS1/ITS4 (White et al. 1990), Bt2a/Bt2b (Glass et al. 1995), and LR5/LR0R (Vilgalys and Hester, 1990), respectively (OK485136, OK631973, and ON358331). BLASTn analysis showed that the ITS, TUB, and LSU sequences had 99% (497/501 bp), 98% (530/539 bp), and 99% (878/882 bp) identity with the Epicoccum sorghinum isolates ESCZO20 (MN944541), CZ01 (MT254851) and Dl16-338 (LN907481), respectively. Maximum likelihood phylogenetic tree revealed that AF21-1-2 clustered with E. sorghinum isolates. For pathogenicity test, leaves of 3-year-old healthy tree peony plant in the field were inoculated with 105 conidia/ml spore suspension (prepared with 30-day-old cultures on PDA), added with 0.1% (v/v) Tween-80. Ten surface-sterilized leaves per plant were sprayed with 30 ml suspension until runoff, a total of 3 plants were inoculated. Leaves sprayed with sterilized water serve as a negative control. Each plant was covered with a plastic bag to maintain high relative humidity at 15 to 23°C and was monitored daily for symptom development. Typical symptoms appeared on more than 80% of the leaves after 7 days of inoculation, while control leaves remained symptomless. Cultures isolated from inoculated leaves had the same morphological and molecular traits as those that were previously used to test Koch's postulates. Based on the morphological and molecular characteristics, the causal agent on tree peony was identified as E. sorghinum (Aveskamp et al. 2010). To our knowledge, this is the first report of E. sorghinum causing leaf spot on tree peony in China. The disease will cause serious economic loss for tree peony if it is not managed properly. This report may provide the basis for diagnosis and control of the disease.

Phylogenetic analysis of the genus Avena based on chloroplast intergenic spacer psbA-trnH and single-copy nuclear gene Acc1.

Two uncorrelated nucleotide sequences, chloroplast intergenic spacer psbA-trnH and acetyl CoA carboxylase gene (Acc1), were used to perform phylogenetic analyses in 75 accessions of the genus Avena, representing 13 diploids, seven tetraploid, and four hexaploids by maximum parsimony and Bayesian inference. Phylogenic analyses based on the chloroplast intergenic spacer psbA-trnH confirmed that the A genome diploid might be the maternal donor of species of the genus Avena. Two haplotypes of the Acc1 gene region were obtained from the AB genome tetraploids, indicating an allopolyploid origin for the tetraploid species. Among the AB genome species, both gene trees revealed differences between Avena agadiriana and the other species, suggesting that an AS genome diploid might be the A genome donor and the other genome diploid donor might be the Ac genome diploid Avena canariensis or the Ad genome diploid Avena damascena. Three haplotypes of the Acc1 gene have been detected among the ACD genome hexaploid species. The haplotype that seems to represent the D genome clustered with the tetraploid species Avena murphyi and Avena maroccana, which supported the CD genomic designation instead of AC for A. murphyi and A. maroccana.

[Effect of Salvia Miltiorrhiza Bunge on expression of osteoprotegerin in cultured human periodontal ligament fibroblasts].

PURPOSE: To study the effect of Salvia Miltiorrhiza Bunge on the expression of osteoprotegerin (OPG) in cultured human periodontal ligament fibroblasts. METHODS: Primary culture of human periodontal ligament fibroblasts was established and the fifth passage cells were used in this study. Concentration-dependent effect of Salvia Miltiorrhiza Bunge on OPG mRNA and OPG protein secretion were determined by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbant assay (ELISA), respectively. The data were analyzed with SPSS15.0 software package. RESULTS: OPG mRNA expression was increased after 1 h exposure to various concentrations of Salvia Miltiorrhiza Bunge compared with the control group (P<0.05). OPG protein secretion was significantly increased after 12 h exposure to various concentrations of Salvia Miltiorrhiza Bunge compared with the control group (P<0.05). CONCLUSION: Salvia Miltiorrhiza Bunge can up-regulate the expression of OPG in cultured human periodontal ligament fibroblasts.

[The clinical study of protraction face mask combining with MEAW technique to correct skeletal Class III malocclusion in the early permanent tooth].

PURPOSE: To investigate the clinical effects of combined multiloop Edgewise arch wire(MEAW) with protraction facemask to treat Class III malocclusion in early permanent dentition, and compare the changes of the periodental tissue and teeth between pre- and post- treatment to explore the mechenism of the method applied to correct Class III malocclusion. METHODS: 23 cases with Class III malocclusion were selected, including 11 males and 12 females, aged from 12 to 14 years old. MEAW and protraction facemask were used to treat Class III malocclusion in early permanent dentition. Lateral cephalometric films were taken for comparison in three stages:before the treatment(T1), seven months (T2) after treatment and in the end of the treatment(T3).SPSS10.0 software package was used for statistical analysis. RESULTS: The alveolar bone changes mainly happaned in the T2 stage, SNA increased by 2.37 degrees in average, OP-MP increased by 4.85 degrees in average; Wits increased by 2. 50 degrees in average. The difference was significant(P<0.05). However there was no significant difference between T2 and T3 stage. In the T2 stage,the overjet and overbite increased 4.43mm and 2.66mm in average, and increase continued after treatment. CONCLUSION: It is suggested that MEAW with protraction facemask is an effective technique to treat Class III malocclusion in early permanent dentition by improving maxillary growth.

[Transoral miniplate fixation of mandibular body fracture without maxillomandibular fixation: report of 45 cases].

PURPOSE: To assess the efficacy of intraoral open reduction of mandibular body fracture using titanium miniplate rigid fixation and intermaxillary traction titanium screw to rigidly tract the jaw during the operation. METHODS: 54 mandibular fractures in 45 patients were included in this study. After general anaesthesia, the intermaxillary traction titanium screw was inserted in the alveolar bone, between the two incisors, between the canine and the first premolar, between the first molar and the second molar, and the intermaxillary traction was finished with 0.5 mm stainless steel wire. After the mandibular arch and occlusion relationship were returned to preoperative condition, transoral mucoperiosteal incision was made to expose the fracture lines and fragments. Two 2.0 mm titanium miniplates were adapted along the Champy's line of ideal osteosynthesis and secured. After operation the stainless steel wire was released. Panoramic radiograph and clinical examination were applied at the first day and three months after operation to exhibit bone union and occlusion. RESULTS: Most patients displayed satisfied occlusion and bone union without major complications. Seventeen patients had numbness of the lower lips after operation, and the symptom was disappeared three months later. Two patients had improvement of numbness of the lower lips. CONCLUSION: Intraoral open reduction of mandibular body fracture using titanium miniplate rigid fixation and intermaxillary traction titanium screw showed high efficiency in fixation of the mandibular arch fractures , which occurred in the body and the angle of the mandible.

[Comparison of friction and abrasion between six different dental materials and natural enamel].

PURPOSE: The purpose of this study was to evaluate and compare the friction and abrasion of six kinds of dental materials that was widely used clinically. The mechanisms were investigated to provide experimental reference for selecting proper restorative material to protect opposite natural enamel of the patients. METHODS: In the experimental groups,pure Ti, Ti alloy, Au-Pd alloy, Ni-Cr alloy, AgHg alloy,ceramic were fabricated into thirty uniform 8.0mmx8.0mmx2.0mm block. Five specimens in each group.In the control group,five recently extracted mandibular third molar of adults were fabricated into 8.0mmx8.0mmx2.0mm block. Steatites were fabricated into discs in the diameter of 25mm and thickness of 2.0mm to act as counter sample materials. The mass loss of each specimen and the opposing steatite were weighted by electric balance. The volume loss of the materials and opposing steatites were analyzed by SPSS11.5 software package and the difference was compared between each group. RESULTS: The ranking of the volume loss of six materials and enamel from the most to the least was group A, group E, group C, group D, group B, group F and group G. Significant difference was found between group A and the other groups. No significance was found between group G and F. The coefficient of friction of group A-G was 0.68, 0.12, 0.11, 0.41, 0.38, 0.48 and 0.65,respectively. CONCLUSION: The six materials in this study were less resistant to wear than natural tooth. The wear of pure Ti, AgHg alloy and Ni-Cr alloy are to enamel.