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BACKGROUND: Anthracnose is one of the most widespread and destructive diseases on Chinese fir. Colletotrichum cangyuanense, Colletotrichum fructicola, Colletotrichum gloeosporioides, and Colletotrichum siamense are the causal agents of anthracnose on Chinese fir. A rapid and accurate diagnosis of different pathogens is critical for the disease management. RESULTS: Phylogenetic tree and sequence similarity analysis showed that the single‐locus ApMat provides superior phylogenetic information and is an appropriate target to distinguish C. cangyuanense, C. fructicola, C. gloeosporioides, and C. siamense. The real‐time PCR assays with the primer sets of MQ‐F/R, 1#C‐F/R, YK‐F/R, and WZ‐F/R, and corresponding TaqMan probes of MQ‐P, 1#C‐P, YK‐P, and WZ‐P were specific for C. cangyuanense, C. fructicola, C. gloeosporioides, and C. siamense, respectively. The sensitivity tests showed that the lowest amount of gDNA that the PCRs can detect was 1 ng of genomic DNA. The validity of the assays was confirmed by directly detecting the pathogens from both the fungal culture and infected Chinese fir. CONCLUSION: These results demonstrated the potential of the TaqMan real‐time PCR targeting the ApMat gene to provide rapid, specific, and reliable molecular detection of C. fructicola, C. gloeosporioides, C. siamense, and C. cangyuanense, respectively. The data also provided a reference solution for the identification of species within Colletotrichum gloeosporioides species complex (CGSC), which share similar morphological characteristics. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Liriodendron chinense × tulipifera is widely planted in China as an ornamental plant. In July 2018, a foliar disease, with an incidence of ~23% trees and ~ 45% leaves per individual tree infected, occurred on L. chinense × tulipifera on the campus of Nanjing Forestry University, Jiangsu Province, China. Symptoms were small brown to dark spots surrounded by a yellow halo initially, which enlarged and coalesced into regular or irregular brown necrotic lesions up to 8.5 ± 1.3 mm across. Fungi were isolated from the margins of the lesions. Three representative isolates (E3‐2, E3‐3 and E3‐4) were selected for phylogenetic analyses. One representative isolate E3‐2 was used for pathogenicity tests and morphological identification. The pathogenicity of isolate E3‐2 to L. chinense × tulipifera was confirmed on 1‐year‐old seedlings with lesions after 5 days. The phenotypic characteristics of the isolates were similar to those of Colletotrichum sp. (Glomerellaceae). Phylogenetic analyses using concatenated sequences of ITS, ACT, CHS, GADPH, CAL, SOD2 and TUB2 placed E3‐2, E3‐3 and E3‐4 in the clade of C. fructicola. Based on the morphological and phylogenetic studies, the isolates were identified as C. fructicola. This is the first report of C. fructicola causing L. chinense × tulipifera leaf spots in China. [ABSTRACT FROM AUTHOR]

Chinese fir (Cunninghamia lanceolata) is a fast‐growing tree species with high economic value. Anthracnose caused by Colletotrichum species poses a serious threat to Chinese fir production. To investigate the Colletotrichum species associated with anthracnose on Chinese fir, a survey was conducted from 2016 to 2020 in China. A total of 52 Colletotrichum isolates was collected from six different provinces: Fujian, Guangdong, Jiangsu, Jiangxi, Shandong and Zhejiang. These isolates were identified using morphological and multilocus phylogenetic analyses with the concatenated sequences of the rDNA internal transcribed spacer (ITS), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), chitin synthase (CHS‐1), actin (ACT), β‐tubulin (TUB2), calmodulin (CAL) and the intergenic region between Apn2 and Mat1‐2‐1 (ApMat). Colletotrichum cangyuanense, C. fructicola, C. gloeosporioides, C. karstii and C. siamense were revealed to be associated with anthracnose on Chinese fir. Pathogenicity tests showed that there were significant differences in the pathogenicity of these Colletotrichum species on the host plants. To our knowledge, this study reports the pathogen diversity of anthracnose on Chinese fir for the first time. [ABSTRACT FROM AUTHOR]

BACKGROUND Bursaphelenchus xylophilus, the pinewood nematode, kills millions of pine trees worldwide every year, and causes enormous economic and ecological losses. Despite extensive research on population variation, there is little understanding of the population‐wide variation spectrum in China. RESULTS: We sequenced an inbred B. xylophilus strain using Pacbio+Illumina+Bionano+Hi‐C and generated a chromosome‐level assembly (AH1) with six chromosomes of 77.1 Mb (chromosome N50: 12 Mb). The AH1 assembly shows very high continuity and completeness, and contains novel genes with potentially important functions compared with previous assemblies. Subsequently, we sequenced 181 strains from China and the USA and found ~7.8 million single nucleotide polymorphisms (SNPs). Analysis shows that the B. xylophilus population in China can be divided into geographically bounded subpopulations with severe cross‐infection and potential migrations. In addition, distribution of B. xylophilus is dominated by temperature zones while geographically associated SNPs are mainly located on adaptation related GPCR gene families, suggesting the nematode has been evolving to adapt to different temperatures. A machine‐learning based epidemic tracking method has been established to predict their geographical origins, which can be applied to any other species. CONCLUSION: Our study provides the community with the first high‐quality chromosome‐level assembly which includes a comprehensive catalogue of genetic variations. It provides insights into population structure and effective tracking method for this invasive species, which facilitates future studies to address a variety of applied, genomic and evolutionary questions in B. xylophilus as well as related species. [ABSTRACT FROM AUTHOR]

Chinese rose (Rosa chinensis) is one of the most popular and widely cultivated flowers worldwide and has extremely high economic and ornamental value. In 2020 wilt disease on R. chinensis was discovered in Pukou District, Nanjing, Jiangsu Province, China. Fungal isolates were obtained from the stems of the rose. According to morphological characteristics and multilocus phylogenetic analyses with the sequences of the rDNA internal transcribed spacer (ITS), translation elongation factor 1‐α gene (TEF1‐α), and part of the RNA polymerase II gene (RPB2), the isolates YJ1 to YJ4 were determined as a new species of Fusarium solani species complex, and named as Fusarium rosicola sp. nov., which is hereby described and illustrated. Pathogenicity of the isolate YJ1 was verified by Koch's postulates. The fungus was determined as the pathogen causing rose vascular wilt. The isolate YJ1 was labelled with green fluorescent protein (GFP), and roots of R. chinensis were inoculated. The result showed that the fungus infected the vascular tissue of the host plants and caused withering of the above‐ground parts, resulting in the death of the whole plant. The GFP‐labelled pathogen was reisolated from the stems and foliage, proving that this is a newly emerged systemic disease on R. chinensis in the world. [ABSTRACT FROM AUTHOR]

Curvularia includes plant pathogenic species with a worldwide distribution and a wide host range, particularly cereals and grass (Poaceae). Chinese fir (Cunninghamia lanceolata) is an important afforestation tree species in southern China, with a high economic value. Leaf blight disease on Chinese fir was discovered in Hunan and Zhejiang, China, and two fungal species were found to be associated with the symptoms. Using morphological and phylogenetic approaches, they were identified as Curvularia spicifera and Curvularia muehlenbeckiae. They were determined to be the pathogens by fulfilling Koch's postulates. Both showed a pathogenicity on Citrus reticulata and Citrus tangerina, which have a similar geographic distribution to Chinese fir. The similar geographic distribution of these hosts may increase the risk of disease. Based on a literature review, leaf blight caused by C. spicifera and C. muehlenbeckiae is recorded here on a gymnosperm for the first time. [ABSTRACT FROM AUTHOR]

Elaeagnus pungens is an ornamental plant used in landscapes and is native to China and Japan. In Nov. 2015, a leaf spot was found on El. pungens in the Sheshan National Forest Park located at Shanghai. A fungus was isolated from the margins of the lesions and one isolate, EP8, selected for identification and pathogenicity tests. Morphological characteristics of the fungus were similar to Epicoccum latusicollum. Phylogenetic analysis using concatenated sequences of ITS, LSU, TUB, and RPB2 also showed that isolate EP8 clustered with strains of E. latusicollum, a relationship supported with a high bootstrap value. This report is the first of E. latusicollum causing leaf spot on El. pungens. [ABSTRACT FROM AUTHOR]

Bambusa multiplex has been broadly cultivated in China and has significant economical, ecological and ornamental importance. A canker on the culm of B. multiplex was first time discovered in 2015 in Shanghai, China. In this study, the fungal isolate XSZ‐1 isolated from the infected tissues was determined to be a pathogen of canker on the culm of B. multiplex by fulfilling Koch's postulates. The fungal pathogen was identified as Fusarium incarnatum based on the morphological characteristics and phylogenetic analyses with the sequences of ITS, TEF‐1α and RPB2. To our knowledge, this is the first report of a canker on the culm of B. multiplex caused by F. incarnatum worldwide. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we aimed to compare and validate the prognostic abilities of preoperative systemic immune cells in hepatocellular carcinoma (HCC) after curative hepatectomy. We developed two nomograms to predict the postoperative recurrence‐free survival (RFS) and overall survival (OS) after comparisons of the systemic immune cell prognostic scores. The two nomograms were constructed based on 305 patients who underwent curative hepatectomy for HCC. The predictive accuracy and discriminative ability of the nomograms were compared with six commonly used staging systems for HCC. The results were validated using bootstrap resampling and an internal validation cohort of 142 patients and an external validation cohort of 169 patients. Necroinflammatory activity in peritumoral liver tissues in the primary cohort was evaluated by hematoxylin and eosin (H&E) staining. Neutrophil, monocyte, and lymphocyte ratio (NMLR) had a higher area under the receiver operating characteristic curves (AUROC) value at both RFS (AUC = 0.603) and OS (AUC = 0.726) compared to that of other systemic immune cell prognostic scores. The independent predictors of RFS or OS, including α‐fetoprotein (AFP), tumor size, tumor number, microvascular invasion, and NMLR, were incorporated into the two nomograms. In the primary cohort, the C‐indexes of the RFS and OS nomograms were 0.705 and 0.797, respectively. The ROC analyses showed that the two nomograms had larger AUC values (0.664 for RFS and 0.821 for OS) than those of the American Joint Commission on Cancer seventh edition, Barcelona Clinic Liver Cancer, Cancer of the Liver Italian Program, Japan Integrated Staging Score, Okuda stage, and the Vauthey's system. These results were verified by internal and external validations. The nomogram‐predicted probability of RFS was associated with peritumoral necroinflammatory activity scores (r = 0.304, P < 0.001). The proposed nomograms had accurate prognostic prediction in patients with HCC after curative hepatectomy. [ABSTRACT FROM AUTHOR]

Stachybotrys eucylindrospora was characterised as a new species in 2007, and we present the first report of this organism isolated from foreign material recovered from a patient. It is probable that isolates of this species have been previously identified as either Stachybotrys chartarum or Stachybotrys cylindrospora. [ABSTRACT FROM AUTHOR]

Background and Aim Controlled attenuation parameter ( CAP) is a novel ultrasound-based elastography method for detection of steatosis severity. This meta-analysis aimed to assess the performance of CAP. Methods Pub Med, the Cochrane Library, and the Web of Knowledge were searched to find studies, published in English, relating to accuracy evaluations of CAP for detecting stage 1 ( S1), stage 2 ( S2), or stage 3 ( S3) hepatic steatosis which was diagnosed by liver biopsy. Sensitivities, specificities, and hierarchical summary receiver operating characteristic ( HSROC) curves were used to examine CAP performance. The clinical utility of CAP was also evaluated. Results Nine studies, with 11 cohorts were analyzed. The summary sensitivities and specificities values were 0.78 (95% confidence interval [ CI], 0.69-0.84) and 0.79 (95% CI, 0.68-0.86) for ≥ S1, 0.85 (95% CI, 0.74-0.92) and 0.79 (95% CI, 0.71-0.85) for ≥ S2, and 0.83 (95% CI, 0.76-0.89) and 0.79 (95% CI, 0.68-0.87) for ≥ S3. The HSROCs were 0.85 (95% CI, 0.81-88) for ≥ S1, 0.88 (95% CI, 0.85-0.91) for ≥ S2, and 0.87 (95% CI, 0.84-0.90) for ≥ S3. Following a 'positive' measurement (over the threshold value) for ≥ S1, ≥ S2, and ≥ S3, the corresponding post-test probabilities for the presence of steatosis (pretest probability was 50%) were 78%, 80% and 80%, respectively; if the values were below these thresholds ('negative' results), the post-test probabilities were 22%, 16%, and 17%, respectively. Conclusions CAP has good sensitivity and specificity for detecting hepatic steatosis; however, based on a meta-analysis, CAP was limited in their accuracy of steatosis, which precluded widespread use in clinical practice. [ABSTRACT FROM AUTHOR]

The cover image, by Lin Huang et al., is based on the Original Article Canker on culm of Bambusa multiplex (Lour.) Raeusch. ex Schult. caused by Fusariumincarnatum (Roberge) Sacc. DOI: 10.1111/jph.12776. [ABSTRACT FROM AUTHOR]