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A Gram-negative, aerobic, motile with paired polar flagella and rod-shaped bacterium strain (56D2T) was isolated from tobacco planting soil in Yunnan, PR China. Major fatty acids were C16 : 1 ω7c (summed feature 3), C16 : 0 and C18 : 1 ω7c (summed feature 8). The polar lipid profile of strain 56D2T consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid and one unidentified glycolipid. Moreover, strain 56D2T contained ubiquinone Q-8 as the sole respiratory quinone. 16S rRNA gene sequence analysis showed that strain 56D2T was closely related to members of the genus Ralstonia and the two type strains with the highest sequence identities were R. mannitolilytica LMG 6866T (98.36 %) and R. pickettii K-288T (98.22 %). The 16S rRNA gene sequence identities between strain 56D2T and other members of the genus Ralstonia were below 98.00 %. Genome sequencing revealed a genome size of 5.87 Mb and a G+C content of 63.7 mol%. The average nucleotide identity values between strain 56D2T and R. pickettii K-288T, R. mannitolilytica LMG 6866 T and R. insidiosa CCUG 46789T were less than 95 %, and the in silico DNA–DNA hybridization values (yielded by formula 2) were less than 70 %. Based on these data, we conclude that strain 56D2T represents a novel species of the genus Ralstonia , for which the name Ralstonia wenshanensis sp. nov. is proposed. The type strain of Ralstonia wenshanensis sp. nov. is 56D2T (=CCTCC AB 2021466T=GDMCC 1.2886T=JCM 35178T).

Three Gram-stain-negative, motile, with amphilophotrichous flagella, and rod-shaped bacteria (LJ1, LJ2T and LJ3) were isolated from lower leaves with black spots on flue-cured tobacco in Yunnan, PR China. The results of phylogenetic analysis based on 16S rRNA gene sequences indicate that all the strains from tobacco were closely related to the type strains of the Pseudomonas syringae group within the P. fluorescens lineage and LJ2T has the highest sequence identities with P. cichorii DSM 50259T (99.92 %), P. capsici Pc19-1T (99.67 %) and P. ovata F51T (98.94 %) . The 16S rRNA gene sequence identities between LJ2T and other members of the genus Pseudomonas were below 98.50%. The average nucleotide identity by blast (ANIb) values between LJ2T and P. cichorii DSM 50259T, P. capsici Pc19-1T and P. ovata F51T were less than 95 %, and the in silico DNA–DNA hybridization (isDDH) values (yielded by formula 2) were less than 70 %. The major fatty acids were C16 : 1ω7c and/or C16 : 1ω6c (summed feature 3), C16 : 0 and C18 : 1ω7c and/or C18 : 1ω6c (summed feature 8). The polar lipids profile of LJ2T consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, two unidentified phospholipids and one unidentified glycolipid. The predominant respiratory quinone was Q-9. The DNA G+C content of LJ2T was 58.4 mol%. On the basis of these data, we concluded that LJ2T represents a novel species of the genus Pseudomonas , for which the name Pseudomonas lijiangensis sp. nov. is proposed. The type strain of Pseudomonas lijiangensis sp. nov. is LJ2T (=CCTCC AB 2021465T=GDMCC 1.2884T=JCM 35177T).

Tobacco is one of the most significant non-food cash crops (Lu et al. 2020). In March 2022, cigar tobacco plants showing characteristic symptoms of vascular discoloration, stem rotting, leaf wilting and rotting were observed in Tengchong city (N 25°3'26″, E 98°25'6″) of Yunnan province, China (Fig. S1). The disease incidence was about 5% on cultivar Yunxue 6 in a 33-ha field. Infected stems were collected from Tengchong for pathogen isolation and 16S rDNA sequence analysis was performed as previously described (Lu et al. 2021). Sequence analysis showed that tobacco isolates (GenBank accession numbers: ON795108, ON795107 and ON795106) had an identical sequence with that of the species type strain of Pectobacterium versatile CFBP 6051T and shared the sequence identities of 99.55% and 99.47% with P. carotovorum DSM 30168T and P. parvum s0421T, respectively. Furthermore, phylogenetic analysis showed that tobacco strains were clustered with Pectobacterium versatile CFBP 6051T (Fig. S2a). In API assays, strain 22TC1 was positive for β-galactosidase activity, reduction of nitrates to nitrites, fermentation of glucose, hydrolysis of esculin and gelatin, assimilation of D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetylglucosamine, malic acid and trisodium citrate; positive for the enzymatic substrates of alkaline phosphatase, leucine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrolase, α-galactosidase, β-galactosidase and α-glucosidase. Furthermore, the average nucleotide identity (ANI) analysis (Richter et al. 2015) showed that strain 22TC1 (GenBank accession number: JAMWYQ000000000) had the highest ANIb score of 96.76% and ANIm value of 97.19% with P. versatile CFBP 6051T. Similarly, in silico DNA-DNA hybridization (isDDH) value was 74.5% compared to P. versatile CFBP 6051T, isDDH values were 35.5-63.7% with the other Pectobacterium species, which below the 70% threshold value for species delineation (Meier-Kolthoff et al. 2021). The phylogenomic analysis also showed that strain 22TC1 was clustered with the species type strain of P. versatile CFBP 6051T. For pathogenicity tests, cell suspension with ten-fold dilution (approx. 1 x 108 CFU/ml) was injected into the leaf axils of two 2-month-old tobacco stems (cv. Yunyan 87). As a control, tobacco seedlings were inoculated with sterile distilled water. The plants were sealed in plastic bags and maintained in a growth chamber at 28°C for 2 d. The symptoms of water-soaked decay were observed within 24 h of inoculation. Whole-plant decay was at 2 days after injection. No symptoms were developed in the controls. Reisolation was performed on diseased stems and the identity of isolated bacteria was confirmed by PCR and sequencing of 16S rRNA. Similar results were obtained in two independent experiments. Based on the above-described data, the causal pathogen of stem rot on cigar tobacco in Tengchong was identified as P. versatile. To our knowledge, this is the first time that P. versatile is found to cause stem rot on tobacco. Pectobacterium species have been reported to cause seed-borne diseases on tobacco seedlings in the floating tray system and soil-borne diseases in tobacco fields (Wang et al. 2017; Xia and Mo 2007). Therefore, studying the possible transmission of the P. versatile to tobacco plants is necessary.

Here, we present the complete genome sequence and annotation of

In this study, we describe the genome sequence of a novel double-stranded RNA (dsRNA) mycovirus, designated as “Rhizoctonia solani partitivirus 15” (RsPV15), from the phytopathogenic fungus Rhizoctonia solani. RsPV15 consists of two genomic double-stranded RNA segments, dsRNA-1 and dsRNA-2, which are 2433 bp and 2350 bp long, respectively. Each of the dsRNA segments contains a single open reading frame, encoding the putative RNA-dependent RNA polymerase and coat protein, respectively. Homology searches and phylogenetic analysis suggested that RsPV15 is a new member of the genus Betapartitivirus within the family Partitiviridae.

Multi-properties concrete (MPC) contains the properties as follows: self-compacting, self-curing, heat dissipation at low water content; low shrinkage; high plasticity keeping and high durability. We applied the concept of “multi-properties concrete” (MPC) during the construction of the West Tower and East Tower both at Guangzhou and Jinji Complex at Shenzhen. The multi-properties concrete is more effective in controlling cracks of concrete, while it is a new type concrete with properties of green and low carbon.