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Actinomycetes, which can produce a variety of bioactive compounds in the metabolic process, is one of the important sources of novel drugs, enzymes, anti-tumor drugs and enzyme inhibitors. It has been the focus of researchers to find and develop Actinomycetes with special characters. Strain XJ-16 is a blue alkali-resistant filamentous bacterium with high antimicrobial activity isolated from saline-alkali land of Xinjiang. Based on the classification, the enzyme production, metabolite antibacterial activity, and antibacterial substance isolation of XJ-16 were explored. which showed that XJ-16 belongs to the blue group of Streptomyces sp, and it can secrete cellulase, lipase, urease, protease, catalase and oxidase during metabolism. In addition, the bacteriostatic substance secreted by the strain XJ-16 showed inhibitory effects against both Gram-positive and Gram-negative bacteria, as well as the yeast Candida albicans. Then it was found that the bacteriostasis produced by XJ-16 has strong tolerance to acid, weak tolerance to alkali, and easy to be inactivated. After tested by HPLC, the retention time of antimicrobial substance was 13.261 min. This study provides a theoretical basis for the search for new antibacterial compounds and the further development of blue alkaline Actinomycetes XJ-16.

Bacterial fruit blotch (BFB), caused by the seed-transmitted pathogen Acidovorax citrulli, poses a serious threat to cucurbitaceous crops worldwide. In this study, two biocontrol bacteria strains, Bacillus amyloliquefaciens (Ba-2) and Pseudomonas fluorescens (2P24), with significant antagonistic activity against A. citrulli were and applied by seed priming to control BFB seed transmission. Artificially infested watermelon and melon seeds were treated with the biocontrol strains by liquid or solid matrix seed priming. The seed bio-priming effects were evaluated under greenhouse conditions. Germination percentages were improved by seed priming treatments for melon, and seedling uniformity was higher for seeds primed with Ba-2 than for seeds from the other treatments for watermelon. Seedling disease incidence of untreated seeds were 6.5% for watermelon and 16.0% for melon, and water-priming resulted in similar disease progress curves as the untreated control. Seed priming with Ba-2 and 2P24 significantly reduced seedling BFB incidence for both watermelon and melon. Evaluation with naturally infested watermelon seeds primed with biocontrol strains indicated that 2P24 seed priming was more effective than Ba-2 (P < 0.05) and 2P24 solid matrix priming, reducing the seedling disease incidence to 1.3%. Seed bio-priming has potential as an effective and eco-friendly approach for suppressing bacterial fruit blotch seed-to-seedling transmission.

Several articles have indicated that circular RNAs are involved in pathogenesis of human cancers. Nevertheless, the role of circ_0091579 in hepatocellular carcinoma (HCC) progression remains to be revealed. Quantitative reverse transcriptase polymerase chain reaction was carried out to examine the expression of circ_0091579 and miR-1287. The proliferation of HCC cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry was performed to analyze cell cycle progression and apoptosis. Western blot assay was conducted to detect the protein expression of CyclinD1, Cleaved caspase3, and pyruvate dehydrogenase kinase 2 (PDK2). Cell glycolysis was evaluated by measuring the uptake of glucose, the production of lactate, and extracellular acidification rate. The target relationship between miR-1287 and circ_0091579 or PDK2 was verified by dual-luciferase reporter assay, RNA immunoprecipitation assay, and RNA-pull down assay. The enrichment of circ_0091579 was enhanced in HCC tissues (n = 77) and four HCC cell lines (HB611, Huh-7, MHCC97, and SNU423) compared with adjacent non-tumor tissues (n = 77) and normal human liver cell line THLE-2. Circ_0091579 mediated the promotion of proliferation and glycolysis and the suppression of apoptosis of HCC cells. MiR-1287 was a direct target of circ_0091579 in HCC cells. MiR-1287 knockdown reversed the effects caused by circ_0091579 interference on the functions of HCC cells. PDK2 could bind to miR-1287 in HCC cells. Circ_0091579 upregulated the enrichment of PDK2 by acting as a sponge of miR-1287 in HCC cells. The influence caused by circ_0091579 intervention on HCC cells was attenuated by overexpression of PDK2. Circ_0091579 interference impeded the progression of HCC in vivo. Circ_0091579 deteriorated HCC by promoting the proliferation and glycolytic metabolism and suppressing the apoptosis of HCC cells via miR-1287/PDK2 axis.

Asparagus (Asparagus officinalis L) is an economically important crop, rich in nutrients, and is also conducive to solving ecological and environmental problems. Plants may acquire benefits from root-associated endophytic bacteria. However, the composition of the endophytic bacterial community associated with the roots of asparagus is poorly elucidated. In this study, the nine root samples of asparagus from three different varieties including Asparagus officinalis var. Grande (GLD), A. officinalis var. Jinglvlu3 (JL3) and A. officinalis var. Jingzilu2 (JZL) were investigated by high-throughput sequencing technology of the 16S rDNA V5-V7 hypervariable region of endophytic bacteria. A total of 16 phyla, 29 classes, 90 orders, 171 families, and 312 genera were identified. Endophytic bacteria diversity and bacteria structure was different among the three varieties and was influenced by rhizosphere soil properties and varieties. In the GLD variety, the main phyla were Proteobacteria, Actinobacteria, and Firmicutes. The main phylum in JL3 and JZL varieties was Proteobacteria. The observations showed that GLD had the highest diversity of endophytes as indicated by the Shannon index (GLD > JZL > JL3). The order of the endophytes richness was GLD > JL3 > JZL. The PCA and PCoA analysis revealed the microbial communities were different between three different asparagus varieties, and the microbial composition of GLD and JZL was more similar. This report provides an important reference for the study of endophytic microorganisms of asparagus. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s12088-021-00926-6) contains supplementary material, which is available to authorized users.

Diseases are critical factors that affect the yield and quality of crops. Therefore, it is of great research value to develop rapid and quantitative methods for identification of common agricultural diseases. This exploratory study involved data analysis of common fungal pathogens using identification modeling based on terahertz spectrum technology. The selected pathogens were Physalospora piricola, Erysiphe cichoracearum, and Botrytis cinerea, which are common fungal pathogens that cause apple ring rot, cucumber powdery mildew, and grape gray mold blight, respectively. Taking polyethylene as the control, the terahertz time-domain spectra, and frequency-domain spectra of samples of the three pathogens were both measured. The absorption and refraction characteristics of these samples in the range of 0.1-2.0 THz were calculated and analyzed, and samples were then divided using the KS algorithm. Terahertz spectrum-image data blocks of the pathogen samples were preprocessed, and the dimensions of data were reduced using non-local mean filtering and the SPA algorithm, respectively. K-nearest neighbors (KNN), support vector machine (SVM), and BP neural network (BPNN), and other algorithms were used for analysis of terahertz images at characteristic frequencies, and for investigating the identification model. The model was quantitatively evaluated, and its imaging visualization was studied. The results suggest that there are significant differences among P. piricola, E. cichoracearum, and B. cinerea in absorption and refraction in the terahertz band. SVM modeling identification results of the three pathogens at the frequency of 1.376 THz were satisfactory, with an Rp of 0.9649, RMSEP of 0.0273, and a high (93.8212%) comprehensive evaluation index F1-score, and a clearly identifiable visualization effect. This study demonstrated the potential of terahertz spectroscopy to be used for identification of common crop pathogens and has provided technical references for the rapid diagnosis and early warning of agricultural diseases.

Four Gram-negative-staining, facultatively anaerobic bacterial isolates were obtained from a fruiting body of the edible mushroom Pleurotus eryngii showing symptoms of soft rot disease in Beijing, China. Partial 16S rRNA gene sequencing, together with partial rpoB sequencing, placed these isolates in the genus Pantoea. Multilocus sequence analysis based on the partial sequences of gyrB, rpoB, infB and atpD revealed Pantoea dispersa and Pantoea gaviniae as their closest phylogenetic relatives and indicated that these isolates constituted a possible novel species. DNA-DNA hybridization studies confirmed the classification of the new isolates as a novel species and phenotypic tests allowed for differentiation from the closest phylogenetic neighbours. The name Pantoea beijingensis sp. nov. [type strain LMG 27579(T) = KCTC 32406(T) = JZB2120001(T) (deposited at Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences)] is proposed.

Fusarium spp. in soil are potential threats to crops, so the purpose of this study was to explore the response of their population levels and species composition to long-term fertilizer applications. Two experiments were established in 1993 (consecutive 13 years) and 1997 (consecutive 9 years), where organic fertilizer (OF) and chemical fertilizer (CF) treatments were conducted in the winter wheat–summer maize rotation system in the North China Plain. Unfertilized soil served as controls. Eight Fusarium species were isolated and identified based on their morphological characteristics and nucleic acid analysis. Four dominant species including F. proliferatum, F. solani, F. equiseti, and F. semitectum accounted for 95% of isolates. No differences in total Fusarium population levels and diversity indices with organic and CF were found. Both fertilizer applications increased population levels of F. equiseti in soil, due to its better competition for nutrients. High nutrients also impacted F. solani p...

A study was conducted in an 11-year field experiment in a winter wheat–summer maize rotation agroecosystem in the North China Plain. We aimed to evaluate the changes in soil physico-chemical parameters and the abundance, diversity and community structure of soil mites, under organic fertilizer (OF) and chemical fertilizer (CF) treatments, compared to unfertilized soil as the control (U). Soil organic matter content, available potassium (K), total nitrogen (N) and hydrolyzable N were significantly higher in the plots under the OF treatment than under the other treatments. Available phosphorus (P) content was similar in OF and CF plots and higher than in the control. After continuous 11-year application, both the organic and chemical fertilizer treatments reduced the abundance and diversity of soil mites. Both types of fertilizer significantly reduced the abundance of Oribatida such as Epilohmannia sp., Xylobates sp., Scheloribates sp., and Cultroribula sp. This result was positively related to the high level of phosphorus in the two treatments, which probably suppressed fungi, thus reducing the food resources for mycophagous mites. However, the organic fertilizer remarkably increased the abundance of r-strategic, predatory Mesostigmata, such as Ascidae, possibly due to abundant prey under the nutrient-rich conditions. However, the number of predatory mites did not increase in the chemical fertilizer treatment. While organic fertilizer application did not increase the overall abundance and diversity of soil mites, especially Oribatida, parallel studies (unpublished) show that the increase in predatory Mesostigmata reflected enhanced biological activity and functioning of the bacterial decomposition pathway especially in the food web of this treatment.

Objectives Obtain endophyte strains with effective resveratrol production from superior grapevine variety Cabernet Sauvignon in Xinjiang and determine related taxonomic position of the strain. Results Seventy-three strains of endophytes, including 23 strains of bacteria, 14 ones of actinomycetes, 24 fungus and 12 yeasts, were isolated, respectively. The distribution law of endophytes was spring (30.14 %) = summer (30.14 %)