First Report of Fusarium verticillioides causing Stem Blight of Schizonepeta tenuifolia in China.

Schizonepeta tenuifolia is an important medicinal plant in China. Over 10000 ha of S. tenuifolia is cultivated in the country annually. However, fungal diseases are a major limiting factor in S. tenuifolia production. In 2022, 50 ha in several S. tenuifolia fields in Hebei province were observed to be severely affected by a disease causing a yield loss of 30%. Results from field surveys suggested an epidemic during seedlings stages that affected S. tenuifolia stems, causing irregularly watery brown lesions. Lesions ranged from 1.5 to 2 × 2.5 to 3 cm. To isolate the causal agent, tissue was removed from the border of lesions and surface sterilized in 75% ethanol for 30 sec and 0.1% HgCl2 for 1 min, then rinsed three times with steriled distilled water(SDW), plated on potato dextrose agar(PDA) at 25℃, and incubated in the dark for 7 days. Five putative isolates of the genus Fusarium were hyphal-tipped on new PDA plates. Isolates were cultured on synthetic low-nutrient agar(SNA) with a ~ 1 × 2-cm strip of sterile filter paper on the agar surface(Nirenberg 1976). Cultures were incubated for 7 to 10 days at 20℃ in dark conditions. When sporulation was observed, agar blocks were mounted on a microscopic slide with a drop of lactophenol cotton blue and examined at 400×. Colonies grew rapidly with abundant pink to violet aerial hyphae. Sporodochia formed on the agar, and the aerial conidiophores branched sparsely, often alternately or oppositely, terminating with up to three verticillate phialides. Microconidia produced on polyphialides and aggregating in heads were unicellular, ovoidal or ellipsoidal, 4.4 to 17 × 1.5 to 4.5 µm. Macroconidia were abundant, falcate to straight, three to five septate, with a distinct foot cell, 27 to 73 × 3.1 to 5.6 µm. Based on morphological characteristics, isolates were tentatively identified as F. verticillioides(A1-Hatmi et al. 2016; Guarro 2013). Pathogenicity tests were performed by injection inoculation of 0.1 mL of conidial suspensions(1×106 conidia/mL) into three S. tenuifolia stems using a disposable needle and syringe. Distilled water was injected into three mock controls. Inoculated plants were placed in a greenhouse at 32 to 34℃ and 95% relative humidity. Typical lesions were observed 7 days after inoculation, except in the control samples. Each treatment was replicated three times. The suspected pathogen was consistently reisolated from diseased tissue according to Koch's postulates, and was found to be morphologically similar to F. verticillioides. Preliminary morphological identification of the pathogen was further confirmed by using genomic DNA extracted from the mycelia of a 7-day-old culture grown on PDA at 25℃. The translation elongation factor 1-α gene(TEF1) was amplified(O'Donnell et al. 1998) and the TEF region(Genbank Accession No. OR105502) was sequenced by Sangon Biotech Co., Ltd.(Shanghai, China) and displayed 100% nucleotide similarity with rDNA-TEF of F. verticillioides(JF740717) separately after a BLASTn search in Genbank. Based on the symptoms, fungal morphology, TEF sequence, and pathogenicity testing, this fungus was identified as F. verticillioides. to our knowledge, this is the first report of F. verticillioides infecting S. tenuifolia in China. This report will promote further research of F. verticillioides on this host and lead to better understanding of disease prevalence, extent of damage, and possible management options.

GWAS and bulked segregant analysis reveal the Loci controlling growth habit-related traits in cultivated Peanut (Arachis hypogaea L.).

BACKGROUND: Peanut (Arachis hypogaea L.) is a grain legume crop that originated from South America and is now grown around the world. Peanut growth habit affects the variety's adaptability, planting patterns, mechanized harvesting, disease resistance, and yield. The objective of this study was to map the quantitative trait locus (QTL) associated with peanut growth habit-related traits by combining the genome-wide association analysis (GWAS) and bulked segregant analysis sequencing (BSA-seq) methods. RESULTS: GWAS was performed with 17,223 single nucleotide polymorphisms (SNPs) in 103 accessions of the U.S. mini core collection genotyped using an Affymetrix version 2.0 SNP array. With a total of 12,342 high-quality polymorphic SNPs, the 90 suggestive and significant SNPs associated with lateral branch angle (LBA), main stem height (MSH), lateral branch height (LBL), extent radius (ER), and the index of plant type (IOPT) were identified. These SNPs were distributed among 15 chromosomes. A total of 597 associated candidate genes may have important roles in biological processes, hormone signaling, growth, and development. BSA-seq coupled with specific length amplified fragment sequencing (SLAF-seq) method was used to find the association with LBA, an important trait of the peanut growth habit. A 4.08 Mb genomic region on B05 was associated with LBA. Based on the linkage disequilibrium (LD) decay distance, we narrowed down and confirmed the region within the 160 kb region (144,193,467-144,513,467) on B05. Four candidate genes in this region were involved in plant growth. The expression levels of Araip.E64SW detected by qRT-PCR showed significant difference between 'Jihua 5' and 'M130'. CONCLUSIONS: In this study, the SNP (AX-147,251,085 and AX-144,353,467) associated with LBA by GWAS was overlapped with the results in BSA-seq through combined analysis of GWAS and BSA-seq. Based on LD decay distance, the genome range related to LBA on B05 was shortened to 144,193,467-144,513,467. Three candidate genes related to F-box family proteins (Araip.E64SW, Araip.YG1LK, and Araip.JJ6RA) and one candidate gene related to PPP family proteins (Araip.YU281) may be involved in plant growth and development in this genome region. The expression analysis revealed that Araip.E64SW was involved in peanut growth habits. These candidate genes will provide molecular targets in marker-assisted selection for peanut growth habits.

Synergistic Action of Commercially Available Fungicides for Protecting Wheat from Common Root Rot Caused by Bipolaris sorokiniana in China.

Wheat (Triticum aestivum) common root rot (CRR) caused by predominant fungal pathogen Bipolaris sorokiniana occurs in all wheat-growing regions worldwide and is difficult to control. In this study, the efficacy of eight fungicides against Bipolaris sorokiniana was examined in in vitro assays, and we determined that the combined application of two fungicides significantly inhibits the growth of fungal mycelium. Half of the maximal effective concentration of a mixture containing fludioxonil and difenoconazole in the ratio 1:4 was 0.0372 mg/liter, and the cotoxicity coefficient was 160.14. Under an environmentally controlled pot assay, seed treatment with the mixture of fludioxonil and difenoconazole in the 1:4 ratio demonstrated the best control efficiency at seedling and adult stages, respectively. The best synergistic mixture on seed treatment was assessed in a 2-year field experiment at Hebei, China. The best control efficacy achieved at the seedling and adult stages was 82.65% and 68.48%, respectively. Overall, the in vitro mycelial growth inhibition assay and controlled-environment and field studies indicated that the synergistic action of a mixture of fludioxonil and difenoconazole provides effective control against wheat CRR. These findings highlight the potential application of the fungicide combination for controlling CRR and reducing the selection pressure on fungal pathogens by lessening the use of various fungicides in the field.

Serum protein biomarkers screening in patients with ischemic stroke by LC-MS/MS.

BACKGROUND: The purpose of this study was to investigate the serum proteins biomarkers by label-free liquid chromatography coupled to tandem mass spectrometry quantification methods in the Chinese patients with acute ischemic stroke (AIS). METHOD: In the study period, sera from 40 AIS patients and 40 normal cases were selected for screening study. The selected protein associations with disease risk were further evaluated by enzyme-linked immunosorbent assay (ELISA) testing of the remaining stroke cases and controls. Its value for biomarkers diagnosis was appreciated through receiver operating characteristic (ROC) curve. RESULTS: Patients versus control levels differences were suggested for 19 proteins (nominal P < 0.05) for stroke, with three proteins having a false discovery rate <0.05. The association of mannose-binding lectin (MBL) with stroke (P < 0.001) was confirmed using ELISA in replication studies. Based on the ROC curve, the optimal serum concentration of MBL as a surrogate marker to support the diagnosis of ischemic cerebral injury was found to be 1050 ug/L, which yielded a sensitivity of 81.8% and a specificity of 80.2%, the area under the curve was 0.812 (95% CI: 0.724-0.876). In multivariate analysis, there was an increased risk of AIS associated with MBL levels ≥1050 ug/L (OR: 4.76, 95% CI: 1.59-10.12) after adjusting for possible confounders. CONCLUSION: The discovery and replication studies presented here show MBL to be a risk marker for AIS in the Chinese population, which appears to be a novel finding.

Prognostic value of cerebrospinal fluid free fatty acid levels in patients with acute ischemic stroke.

In this study, prognostic value of cerebrospinal fluid (CSF) free fatty acid (FFA) levels in patients confirmed with acute ischemic stroke (AIS) was evaluated in a Chinese population. A prospective cohort designed study was conducted at our hospital of the Emergency department from November, 2012 to September, 2014. The National Institutes of Health Stroke Scale (NIHSS) score on admission was applied to assess CSF levels of FFA and specific severity degree of stroke. Evaluation of the prognostic outcomes of those stroke patients used the modified Rankin scale scores at 90-days. Logistic regression analysis analyzed the prognostic value of FFA. NIHSS score results suggested a positive relationship between levels of CSF FFA levels and severity of stroke. There was an obviously higher trend of CSF FFA levels in patients with CE stroke than those of the non-CE stroke patients, with statistically difference (P < 0.05). Further, CSF FFA levels were evidently lower in those 73 patients with favorable outcome when compared to those with unfavorable outcomes [0.21(IQR, 0.11-0.28) mmol/L vs. 0.36 (IQR, 0.27-0.50) mmol/L, P < 0.0001, P < 0.0001]. Multivariate analysis results after possible confounders adjustment indicated that there was an increased risk of unfavorable outcome associated with CSF FFA levels ≥0.29 mmol/L (OR 5.12, 95%CI: 2.35-10.28; P < 0.0001). Collectively, CSF level of FFA at admission was suggested to be a useful, independent short-term prognostic marker in Chinese patient with AIS.

[A field trial for evaluating the safety of recombinant human interferon alpha-2b for nasal spray].

OBJECTIVE: To evaluate the safety of recombinant human interferon alpha-2b for nasal spray for the prevention of SARS and other upper respiratory viral infections. METHODS: Field epidemiologic evaluation was conducted, the design was randomized and had a synchronously parallel control group. In the study, the drugs were given for five days and all subjects were followed up for ten days. RESULTS: During the period of using interferon, body temperature of the experimental group was normal compared to the control group. Experimental group had more influenza-like symptoms than the control group (P < 0.05), such as headache (4.83%-7.09%), dizziness (7.17%-11.63%), lassitude (8.55%-15.06%), muscular soreness (4.43%-7.09%), pharynx dryness (12.10%-17.85%), angina (6.25%-8.72%), abdominal pain (2.30%-5.50%) and diarrhea (2.45%-5.66%). Most of side effects reached their peak with in the first 3 days. Except for pharynx dryness, the incidences of all other side effects declined after completion of the use of the trial drug, and incidences of some symptoms in experimental group were lower than those of the control group. There were no significant differences in the symptoms of cough and expectoration between the experimental group and the control group. The incidence of exanthem in the control group was significantly higher than that in the experimental group. The side effect of bloody nasal mucus was not observed in experimental group, which had been reported by other authors in several volunteer studies. CONCLUSION: Using recombinant human interferon alpha-2b for nasal spray could lead to some influenza-like symptoms, however, all those symptoms were mild , reversible, and relieved after completion of the use of the trial drug. No serious side effects were found during the period of following up. The authors conclude that the drug is safe.