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1.
Plant Dis ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170445

RESUMO

In June 2021, a disease of stem and leaf rot was observed on lily cultivar 'Tresor' with approximately 20% disease incidence in fields at Huaiyin District (119°04'N, 33°63'E) of Huaian County, Jiangsu Province. The roots and bulbs of symptomatic plants were brown and rotten, with sunken lesions. Symptomatic plants showed short, discolored leaves, and eventually lead to stem wilt and death of the whole plants (Fig. 1A and Fig. 3C). To isolate the pathogen, necrotized plant tissues were surface sterilized with 2% sodium hypochlorite for 2 min followed by 70% ethanol for 30 s and rinsed with sterile water. About 4 mm × 4 mm of diseased tissues were placed on potato dextrose agar (PDA) followed by incubation at 25°C in the dark for 5 days. The pure cultures were obtained by the hyphal-tip method. A total of four fungal isolates with similar colony characteristics were recovered. To determine the identity of the four isolated fungal isolates, genomic DNA was extracted using the method previously described (Khan et al. 2021), the sequences of the internal transcribed spacer (ITS), the translation elongation factor 1α (TEF1) and the RNA polymerase II beta subunit (RPB2) genes were analyzed with primers ITS1/ITS4 (White et al. 1990), EF1/ EF2 (O'Donnell et al. 1998), and 5F2/7cR (Reeb et al. 2004), respectively. The three gene sequences of four isolates showed 99.9 %-100% identities. The531 bp (ITS), 699 bp (TEF1), and 900 bp (RPB2) sequences of a representative isolate (JH-37) were deposited in GenBank with acce. nos. OR195729, OR195041 and OR195040, respectively. A phylogenetic tree was constructed using the concatenated three gene sequences of JH-37 and that of the related Fusarium species based on Maximum Likelihood (Fig.2). JH-37 was grouped together with the F. armeniacum strain CBS 485.94 (AB587001, GQ915501, GQ915485), and shared 99.9 % concatenated sequence identity. The three gene sequences of the strain JH-37 shared 100%, 99.85%, 99.89% identity to F. armeniacum strain CBS 485.94 using MEGA 7 software (Kuma et al. 2016) analysis, and with 94%, 95% and 100% coverage by BLAST analysis. The colony of JH-37 on PDA at 25°C for 5 days was white with yellow-brown pigmentation in the center (Fig. 1B-C). From 10-day-old cultures grown on Spezieller Nahrstoffarmer agar (SNA), macroconidia (n = 50) were falcate, slender, curved dorsiventrally, tapering towards both ends, 3 to 4 septate, and measured 24.2 to 50.0 × 2.6 to 4.2 µm. The microconidia (n = 50) were straight or slightly curved, septate 0 to 2, and measured 6.8 to 20.0× 2.1 to 3.7 µm (Fig.1D-F). These morphological characteristics were consistent with Fusarium spp. (Leslie and Summerell 2006). A pathogenicity test of JH-37 was performed on potted lily ('Tresor') under greenhouse conditions. Healthy lily bulbs were selected and one bulb was sown in soil of each pot. Inoculation was performed 60 days after sowing. Bulbs of the lily plants were wounded with needles and inoculated with 5 mL of conidia suspension (1×107 conidia/mL) in the soil around bulb or an equal amount of sterilized water as a control. This experiment had three replicates. After 15 days of inoculation, typical symptoms of bulb rotten, and leaf wilt, similar to the original field symptoms, appeared on the inoculated plants but not on the controls (Fig.3). The same fungus was reisolated from the diseased plants, as identified based on morphology and molecular evidence, which confirmed the Koch's postulate. To our knowledge, this is the first report that F. armeniacum caused Fusarium wilt on Lilium spp. in China. Further, our result could help to develop effective disease management strategies against lily wilt disease.

2.
Sci Total Environ ; 912: 169624, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38157901

RESUMO

The energy sector stands out as a main contributor to increasing global methane (CH4) emissions. Given China's heavy dependence on energy imports, a closer examination of its oil and gas-related CH4 emissions becomes imperative. This study conducts an in-depth analysis of China's contribution to global CH4 emissions stemming from its consumption of crude oil and natural gas since 2000. The results indicate that CH4 emissions from crude oil and natural gas imports rose from 614 Gg in 2000 to 7692 Gg in 2019. When considering domestic production, the demand-induced CH4 emissions in 2019 increased to approximately 10754 Gg (equivalent to 320 Mt CO2-eq and 887 Mt CO2-eq based on global warming potential (GWP) values at the 100-year and 20-year time period), of which 72 % were related to crude oil and natural gas imports. The primary contributor to this increase in CH4 emissions was the expansion of the trade scale. The growth trend of crude oil imports-induced CH4 emissions was also positively influenced by emission intensity and trade structure, but these two drivers had a negative impact on the growth of natural gas imports-induced CH4 emissions. The virtual transfer of CH4 emissions via international oil and gas trade requires urgent policy attention. In collaboration with its trading partners, China should take aggressive actions to achieve meaningful mitigation in CH4 emissions associated with the oil and gas trade.

3.
Plant Dis ; 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337446

RESUMO

Melon (Cucumis melo L.) is a member of the Cucurbitaceae family, and is an important economic and horticultural crop. In March 2022, melon plants in greenhouses exhibited severe leaf yellow spot symptoms in Changjiang County (109°13'N, 19°28'E), Hainan Province. The incidence of the disease was about 30-50%. Lesions initially appeared as yellow dots on leaves and expanded irregularly. Gradually, brown spots appeared, and finally the whole leaves turned yellow and resulted in blighting and death of foliage (Figure 1.). A total of four symptomatic plants were sampled from about 0.2 ha of an area. Symptomatic leaves were excised, surface disinfected with 2% (w/v) NaOCl, rinsed three times with sterile distilled water, and placed on potato dextrose agar (PDA) followed by incubation at 25°C in the dark for 5 days. The pure cultures were obtained by the hyphal-tip method. A total of eight fungal isolates with similar colony characteristics were recovered from the four symptomatic plants. Three DNA fragments (ITS, TEF1, and RPB2) of the eight isolates showed 100% sequence identity based on the molecular identification methods described below. Therefore, one of the isolates, M2JP-3, was chosen for identification and test of the pathogenicity. The colony of M2JP-3 on PDA at 25°C for 5 days was white with yellow-brown pigmentation in the center (Figure 2A-B). From 10-day-old cultures grown on CLA (Fisher et al. 1982), macroconidia (n = 50) were falcate, slender, curved dorsiventrally, tapering towards both ends, 3 to 7 septate, and measured 24.5 to 52.1 x 3.7 to 4.7 µm. The microconidia (n = 50) were straight or slightly curved, septate 0 to 2, and measured 9.9 to 16.3 x 2.5 to 3.7 µm (Figure 2C-E). For molecular identification, genomic DNA was extracted using the method previously described (Khan et al. 2021),the internal transcribed spacer (ITS), translation elongation factor 1α (TEF1) and DNA-dependent RNA polymerase subunit II (RPB2) were amplified, respectively, using primers ITS1/ITS4 (White et al. 1990), EF1/ EF2 (O'Donnell et al. 1998), and 5F2/7cR (Reeb et al. 2004). The 529 bp (ITS), 723 bp (TEF1), and 965bp (RPB2) sequences were deposited in GenBank with acce. nos. OP303211, OP312675 and OP312674, respectively. A phylogenetic tree was constructed using the concatenated three gene sequences of M2JP-3 and that of the Fusarium incarnatum-equiseti species complex (FIESC) (Xia et al. 2019) based on Maximum Likelihood (Figure 3). M2JP-3 was grouped together with the F. pernambucanum strain NRRL 32864 (accession no. GQ505702 for ITS, GQ505613 for TEF1and GQ505791 for RPB2), and shared 100% concatenated sequence identity. For pathogenicity tests of M2JP-3, seeds of melon cultivar Jinmeiren were surface disinfected and sowed in soil in three replicated pots in a greenhouse at 26 °C under natural light. Healthy leaves of the melon plants were wounded with needles and inoculated with mycelial plugs of M2JP-3 or PDA plugs as control. . Symptoms similar to the original greenhouse symptoms were observed at 7 days after inoculation (Figure 4). The control leaves were asymptomatic. The same fungus was reisolated from the inoculated leaves, as identified based on morphology and molecular evidence, which confirmed the Kochs' postulates. To our knowledge, this is the first time Fusarium pernambucanum has been recorded causing leaf yellow spot disease on melon. Further, findings of the present study will help to develop effective disease management strategies against Fusarium pernambucanum Leaf Yellow Spot on melon in China.

4.
Biomed Res Int ; 2022: 5960004, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060140

RESUMO

Microbial inoculants are an important tool for increasing arable land productivity and decreasing mineral fertilizer application. This study was aimed at isolating and identifying endophytic antagonistic bacteria from lily (Lilium davidii var. unicolor) roots grown in Northwestern China and at evaluating their antifungal activity and plant growth-promoting characteristics. For this purpose, endophytic bacteria were isolated from plant roots, and plant growth-promoting strains were identified. One bacterial strain, isolated from the root part, was identified as Bacillus halotolerans based on 16S rRNA gene sequence analysis and was designated as LBG-1-13. The strain showed antagonistic activities against important plant pathogens of lily including Botrytis cinerea, Botryosphaeria dothidea, and Fusarium oxysporum. The highest percentage of growth inhibition, i.e., 71.65 ± 2.39%, was observed for LBG-1-13 against Botryosphaeria dothidea followed by 68.33 ± 4.70% and 48.22 ± 4.11% against Botrytis cinerea and Fusarium oxysporum, respectively. Meanwhile, the isolated strain also showed plant growth-promoting traits such as the production of indole-3-acetic acid (IAA), siderophore, ACC deaminase, and phosphate solubilization activity. The strain showed ACC deaminase activity and was able to cleave 58.41 ± 2.62 nmol α-ketobutyrate (mg protein)-1 min-1. The strain exhibited tolerance to salt and drought stress in an in vitro experiment. The strain LBG-1-13 was able to grow in the presence of 10% NaCl and 20% polyethylene glycol (PEG) in the growth medium. Inoculation of Lilium varieties, Tresor and Bright Diamond, with LBG-1-13 enhanced plant growth under greenhouse and field conditions, respectively. All these results demonstrated that Bacillus halotolerans LBG-1-13 could be utilized as a good candidate in the biocontrol of lily disease and plant growth promotion in sustainable agriculture.


Assuntos
Lilium , Ascomicetos , Bacillus , Bactérias/genética , Botrytis , Fusarium , RNA Ribossômico 16S/genética
5.
PLoS One ; 17(6): e0269640, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35714148

RESUMO

A plant growth-promoting and antifungal endophytic bacteria designated as Ld-08 isolated from the bulbs of Lilium davidii was identified as Pseudomonas aeruginosa based on phenotypic, microscopic, and 16S rRNA gene sequence analysis. Ld-08 exhibited antifungal effects against Fusarium oxysporum, Botrytis cinerea, Botryosphaeria dothidea, and Fusarium fujikuroi. Ld-08 showed the highest growth inhibition, i.e., 83.82±4.76% against B. dothidea followed by 74.12±3.87%, 67.56±3.35%, and 63.67±3.39% against F. fujikuroi, B. cinerea, and F. oxysporum, respectively. The ethyl acetate fraction of Ld-08 revealed the presence of several bioactive secondary metabolites. Prominent compounds were quinolones; 3,9-dimethoxypterocarpan; cascaroside B; dehydroabietylamine; epiandrosterone; nocodazole; oxolinic acid; pyochelin; rhodotulic acid; 9,12-octadecadienoic acid; di-peptides; tri-peptides; ursodiol, and venlafaxine. The strain Ld-08 showed organic acids, ACC deaminase, phosphate solubilization, IAA, and siderophore. The sterilized bulbs of a Lilium variety, inoculated with Ld-08, were further studied for plant growth-promoting traits. The inoculated plants showed improved growth than the control plants. Importantly, some growth parameters such as plant height, leaf length, bulb weight, and root length were significantly (P ≤0.05) increased in the inoculated plants than in the control un-inoculated plants. Further investigations are required to explore the potential of this strain to be used as a plant growth-promoting and biocontrol agent in sustainable agriculture.


Assuntos
Antifúngicos , Lilium , Lilium/genética , Filogenia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Pseudomonas aeruginosa/genética , RNA Ribossômico 16S/genética
6.
Sci Total Environ ; 832: 155019, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35381243

RESUMO

This study aims to identify methane (CH4) emission flows along global supply chains from both production- and consumption-based perspectives and their temporal changes from 2000 to 2014. We employed the structural path analysis (SPA) method to examine the embodied CH4 emission trade through inter-sectoral and inter-regional supply chains. Production activities in the sector of Agriculture (such as crop and animal production) and consumption activities in Construction (such as infrastructure) were the most significant contributors to global CH4 emission increases during 2000-2014. Agriculture and Mining (such as coal mining) accounted for large shares of global embodied CH4 trade at the final consumption tier (i.e., the trade of final goods or services), while Food (such as beverages and tobacco) and Heavy manufacturing (such as steel or automobile manufacturing) were significant contributors to embodied CH4 emissions in the trade of intermediate goods or services directly used to produce final goods or services. This finding highlights the different potential of the sectors for CH4 abatement along global supply chains. The United States imported the most embodied CH4 emissions from foreign areas in 2000 in contrast to China, which dominated imports in 2014. Over 80% of China's embodied CH4 emissions in 2014 were related to intermediate production along global supply chains due to industrial upgrading. India surpassed China as the largest direct emitter for producing final goods or services. Given the critical role of non-CO2 greenhouse gases in global climate change, the spatiotemporal changes of CH4 emissions in global supply chains can help explore the justified allocation of reduction responsibility between countries and sectors connected by the chains.


Assuntos
Gases de Efeito Estufa , China , Comércio , Indústrias , Internacionalidade , Metano/análise
8.
Antonie Van Leeuwenhoek ; 115(3): 353-364, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35088183

RESUMO

A bacterial strain, designated AETb3-4T was isolated from the rhizosphere of lily. Comparison of 16S rRNA gene sequences showed that the sequence from strain AETb3-4T exhibits high sequence similarity with those of Arthrobacter silviterrae KIS14-16T (97.9%), Arthrobacter livingstonensis LI2T (97.2%) and Arthrobacter stackebrandtii CCM 2783T (97.0%). Whole genome average nucleotide identity (ANI) and the digital DNA-DNA hybridization (dDDH) values between strain AETb3-4T and the reference strains A. silviterrae DSM 27180T, A. livingstonensis L12T and A. stackebrandtii DSM 16005T were below 83.6% and 27.7%, respectively, values which are considerably below the proposed thresholds for the species delineation, consistent with the proposal that strain AETb3-4T represents a novel species. The genome size of strain AETb3-4T is 4.33 Mb and the genomic DNA G + C content is 67.3%. The main polar lipids were identified as phosphatidylglycerol, diphosphatidylglycero, phosphatidylinositol and an unidentified glycolipid. The major fatty acids (> 10%) were identified as anteiso-C15: 0 and anteiso-C17: 0. The predominant menaquinone was found to be menaquinone 9 (MK-9) (H2) (82.2%). Phenotypic tests allowed the strain to be differentiated from its close phylogenetic neighbors. Based on the results obtained, it is proposed that the strain AETb3-4T (= CFCC 16390T = LMG 31708T) represents a novel species in the genus Arthrobacter, for which the names Arthrobacter wenxiniae sp. nov. is proposed. In addition, the novel strain AETb3-4T has multiple plant growth-promoting characters including ACC-deaminase activity and production of IAA. Furthermore, the genome contains secondary metabolite biosynthesis gene clusters, including a carotenoid biosynthetic gene cluster, suggesting potential capacities for secondary metabolite synthesis. These data suggest that strain AETb3-4T may have potential applications both in medicine and sustainable agriculture.


Assuntos
Arthrobacter , Técnicas de Tipagem Bacteriana , Carotenoides , DNA Bacteriano/genética , Ácidos Graxos , Família Multigênica , Hibridização de Ácido Nucleico , Peptidoglicano , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2
9.
Sci Total Environ ; 807(Pt 3): 151076, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34678371

RESUMO

There is growing awareness and concern on methane (CH4) emissions from China's oil and natural gas (ONG) systems owing to the carbon neutral target. This paper aims to present a comprehensive review on the bottom-up inventories of the CH4 emissions from the perspective of the ONG systems in China. The trend and magnitude of total emissions in the last four decades were revealed and limitations of current estimations were explored. Previous studies showed that the average CH4 emissions from China's ONG systems have almost tripled from 1980 (760 Gg) to 2015 (2180 Gg) with a trend of steady increase. However, the estimated values varied by an order-of-magnitude with the largest discrepancy of 2700 Gg. This discrepancy was unlikely caused mainly by the incompleteness of estimation, since dominant emission sources were all covered by representative studies. Moreover, the differences of activity-level data were within ±10%, which ruled out the possibility that it was the main contributor to the large discrepancies. The emissions estimate has huge variation in large part because of differences in assumed emission factors (EFs) that vary by an order of magnitude. The difficulty was to determine which of the EFs were accurate due to measurement-based data availability. Thus, the large discrepancies stem from the scarcity of publicly available data, which enlarged the impact from various methods adopted by previous studies. For better understanding of CH4 emissions from the ONG systems in China, the measurements of facility-level emissions and statistics on the ONG infrastructure are required urgently. Due to the high cost and experience-oriented measurement work, international cooperation and communications are critical prerequisites for future CH4 emission estimates and effective mitigation strategies.


Assuntos
Metano , Gás Natural , China , Cooperação Internacional
10.
BMC Plant Biol ; 21(1): 465, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645404

RESUMO

BACKGROUND: Lilium is an important ornamental bulb, possesses medicinal properties, and is also edible. Species within the Lilium genus share very similar morphology and macroscopic characteristics, thus they cannot be easily and clearly distinguished from one another. To date, no efficient species-specific markers have been developed for classifying wild lily species, which poses an issue with further characterizing its medicinal properties. RESULTS: To develop a simple and reliable identification system for Lilium, 45 representative species from 6 sections were used to develop a DNA barcoding system, which was based on DNA sequence polymorphisms. In this study, we assessed five commonly used DNA barcode candidates (ITS, rbcL, ycf1b, matK and psbA-trnH) and five novel barcode candidates obtained from highly variable chloroplast genomic regions (trnL-trnF, trnS-trnG, trnF-ndhJ, trnP-psaJ-rpI33 and psbB-psbH). We showed that a set of three novel DNA barcodes (ITS + trnP-psaJ-rpI33 + psbB-psbH) could be efficiently used as a genetic marker to distinguish between lily species, as assessed by methods including DNAsp, BI and ML tree, and Pair Wise Group (PWG). CONCLUSIONS: A rapid and reliable DNA barcoding method was developed for all 45 wild Lilium species by using ITS, trnP-psaJ-rpI33, and psbB-psbH as DNA barcoding markers. The method can be used in the classification of wild Lilium species, especially endangered species, and also provides an effective method for selective lily breeding.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Espécies em Perigo de Extinção , Marcadores Genéticos , Genoma de Cloroplastos , Lilium/classificação , Lilium/genética , Plantas Medicinais/genética , Análise de Sequência de DNA , Variação Genética , Filogenia , Especificidade da Espécie
11.
Biomed Res Int ; 2021: 9930210, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395628

RESUMO

The present study was aimed at isolating endophytic fungi from the Asian culinary and medicinal plant Lilium davidii and analyzing its antifungal and plant growth-promoting effects. In this study, the fungal endophyte Acremonium sp. Ld-03 was isolated from the bulbs of L. davidii and identified through morphological and molecular analysis. The molecular and morphological analysis confirmed the endophytic fungal strain as Acremonium sp. Ld-03. Antifungal effects of Ld-03 were observed against Fusarium oxysporum, Botrytis cinerea, Botryosphaeria dothidea, and Fusarium fujikuroi. The highest growth inhibition, i.e., 78.39 ± 4.21%, was observed for B. dothidea followed by 56.68 ± 4.38%, 43.62 ± 3.81%, and 20.12 ± 2.45% for B. cinerea, F. fujikuroi, and F. oxysporum, respectively. Analysis of the ethyl acetate fraction through UHPLC-LTQ-IT-MS/MS revealed putative secondary metabolites which included xanthurenic acid, valyl aspartic acid, gancidin W, peptides, and cyclic dipeptides such as valylarginine, cyclo-[L-(4-hydroxy-Pro)-L-leu], cyclo(Pro-Phe), and (3S,6S)-3-benzyl-6-(4-hydroxybenzyl)piperazine-2,5-dione. Other metabolites included (S)-3-(4-hydroxyphenyl)-2-((S)-pyrrolidine-2-carboxamido)propanoic acid, dibutyl phthalate (DBP), 9-octadecenamide, D-erythro-C18-Sphingosine, N-palmitoyl sphinganine, and hydroxypalmitoyl sphinganine. The strain Ld-03 showed indole acetic acid (IAA) production with or without the application of exogenous tryptophan. The IAA ranged from 53.12 ± 3.20 µg ml-1 to 167.71 ± 7.12 µg ml-1 under different tryptophan concentrations. The strain was able to produce siderophore, and its production was significantly decreased with increasing Fe(III) citrate concentrations in the medium. The endophytic fungal strain also showed production of organic acids and phosphate solubilization activity. Plant growth-promoting effects of the strain were evaluated on in vitro seedling growth of Allium tuberosum. Application of 40% culture dilution resulted in a significant increase in root and shoot length, i.e., 24.03 ± 2.71 mm and 37.27 ± 1.86 mm, respectively, compared to nontreated control plants. The fungal endophyte Ld-03 demonstrated the potential of conferring disease resistance and plant growth promotion. Therefore, we conclude that the isolated Acremonium sp. Ld-03 should be further investigated before utilization as a biocontrol agent and plant growth stimulator.


Assuntos
Acremonium/química , Antifúngicos/farmacologia , Ascomicetos/crescimento & desenvolvimento , Botrytis/crescimento & desenvolvimento , Fusarium/crescimento & desenvolvimento , Lilium/microbiologia , Reguladores de Crescimento de Plantas/farmacologia , Acetatos/química , Acetatos/farmacologia , Acremonium/isolamento & purificação , Acremonium/fisiologia , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Cebolinha-Francesa/efeitos dos fármacos , Cebolinha-Francesa/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Resistência à Doença , Endófitos/isolamento & purificação , Endófitos/fisiologia , Fusarium/efeitos dos fármacos , Ácidos Indolacéticos/química , Ácidos Indolacéticos/isolamento & purificação , Ácidos Indolacéticos/farmacologia , Metabolômica/métodos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Raízes de Plantas/microbiologia , Metabolismo Secundário , Espectrometria de Massas em Tandem
12.
Antonie Van Leeuwenhoek ; 114(8): 1213-1224, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34002321

RESUMO

A novel Gram-stain-negative, aerobic and rod-shaped bacterium with a single polar flagellum or a stalk at the end of the cell, was isolated from maize roots in the Fangshan District of Beijing, People's Republic of China. The new strain designated 774T produced indole acetic acid (IAA). The 16S rRNA gene sequence analysis indicated that strain 774T belongs to the genus Caulobacter and is closely related to Caulobacter flavus RHGG3T, Caulobacter zeae 410Tand Caulobacter radices 695T, all with sequence similarities of 99.9%. The genome size of strain774T was 5.4 Mb, comprising 5042 predicted genes with a DNA G+C content of 68.7%.Three striking lasso peptide biosynthetic gene clusters and two IAA synthesis genes belonging to the TPM pathway were also found in the genome of strain 774T. The average nucleotide identity values and digital DNA-DNA hybridization values of the strain774T with its closely phylogenetic neighbours were less than 91.5% and 45.0%, respectively, indicating a new Caulobacter species. The major fatty acids of strain774T were identified as C16: 0 (27.7%), summed feature 3 (C16: 1ω6c and/or C16: 1ω7c) (12.6%) and summed feature 8 (C18: 1ω7c and/or C18: 1ω6c) (42.9%).The major polar lipids consisted of phosphatidyl-glycerol and glycolipids. The predominant ubiquinone was identified as Quinone 10. Based on the polyphasic characterization, strain 774T represents a novel species of the genus Caulobacter, for which the name Caulobacter endophyticus sp. nov. is proposed with 774T (= CGMCC 1.16558T = DSM 106777T) as the type strain.


Assuntos
Caulobacter , Zea mays , Técnicas de Tipagem Bacteriana , Caulobacter/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Humanos , Ácidos Indolacéticos , Família Multigênica , Peptídeos , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo , Ubiquinona
13.
Int J Syst Evol Microbiol ; 70(10): 5531-5538, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32915126

RESUMO

Two nifH gene-harbouring bacterial strains were isolated from rhizospheres of different vegetable plants grown in different regions of northern PR China. The two strains possessed almost identical 16S rRNA gene sequences. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the two strains were 99.21 and 93.6% respectively, suggesting they belong to one species. Based on 16S rRNA gene phylogeny, the two strains were clustered together with Paenibacillus rhizophilus 7197T, Paenibacillus sabinae T27T and Paenibacillus forsythiae T98T, but on a separate branch. Novelty of the species was confirmed by ANI and dDDH comparisons between the type strain 7124T and its closest relatives, since the obtained values were considerably below the proposed thresholds for the species delineation. The genome size of strain 7124T was 5.40 Mb, comprising 5050 predicted genes with a DNA G+C content of 52.3 mol%. The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids. The major cellular fatty acids were anteiso-C15  :  0 (52.9%) and C16  :  0 (23.4 %). Menaquinone-7 was reported as the major respiratory quinone. The diamino acid in the cell-wall peptidoglycan was found to be meso-diaminopimelic acid. Based on phylogenetic, genomic, chemotaxonomic and phenotypic data, the two isolates are considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus apii sp. nov. is proposed, with 7124T (=DSM 103172T=CGMCC 1.15689T) as type strain.


Assuntos
Paenibacillus/classificação , Filogenia , Rizosfera , Microbiologia do Solo , Verduras/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Paenibacillus/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
Syst Appl Microbiol ; 43(6): 126135, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32971439

RESUMO

Two plant-associated bacterial strains were isolated from Beijing, China. The two strains possessed almost identical 16S rRNA gene sequences. However, REP-PCR fingerprint patterns discriminated that they were not from one clonal origin. The average nucleotide identity (ANI) value and the digital DNA-DNA hybridization (dDDH) value between the two strains were 99.4% and 94.7%, respectively, suggesting that they belonged to the same species. The 16S rRNA gene phylogeny analysis indicated that the two strains belonged to the genus Variovorax and were closely related to V. paradoxus NBRC 15149T and V. boronicumulans BAM-48T. Their phylogenetic relationship were confirmed in both phylogenetic trees constructed with house-keeping gene sequences and concatenated core genes of the genome. The ANI and dDDH comparisons among 502T and the most related type strains showed values below the accepted threshold for species discrimination. The genome sizes of strains 502T and T529 were 6.76 and 6.69 Mbp, respectively. The strain 502T had 6,227 predicted genes with DNA G+C content of 67.4 %. The respiratory quinone was ubiquinone-8 and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphospatidylglycerol. The major fatty acids of strain 502T were C10: 03-OH (26.2%), C16:0 (12.9%), C17:0 cyclo (14.5%) and summed feature 3 (21.4%). Furthermore, both strains showed the potential of plant growth promotion. Based on these results, the two isolates could be considered to represent a novel species of the genus Variovorax, for which the name Variovorax beijingensis sp. nov., is proposed, with 502T (= DSM 106862T = CGMCC 1.16560T) as the type strain.


Assuntos
Comamonadaceae/classificação , Filogenia , Solanum lycopersicum/microbiologia , Zea mays/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Pequim , Comamonadaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
15.
Int J Syst Evol Microbiol ; 70(9): 5019-5025, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32783806

RESUMO

A novel Gram-stain-negative, aerobic, rod-shaped and indole acetic acid-producing strain, designated 7209-2T, was isolated from rhizosphere of rape (Brassica napus L.) grown in the Yakeshi City, Inner Mongolia, PR China. The 16S rRNA gene sequence analysis indicated that strain 7209-2T belongs to the genus Rhizobium and is closely related to Rhizobium rosettiformans W3T, Rhizobium ipomoeae shin9-1T and Rhizobium wuzhouense W44T with sequence similarities of 98.2, 98.1 and 97.9 %, respectively. Phylogenetic analysis based on concatenated housekeeping recA and atpD gene sequences showed that strain 7209-2T formed a group together with R. wuzhouense W44T and R. rosettiformans W3T, with sequences similarities of 92.6 and 91.1 %, respectively. The genome size of strain 7209-2T was 5.25 Mb, comprising 5027 predicted genes with a DNA G+C content of 61.2 mol%. The average nucleotide identity and digital DNA-DNA hybridization comparisons among 7209-2T and reference strains for the most closely related species showed values below the accepted threshold for species discrimination. The major fatty acids of strain 7209-2T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and summed feature 2 (C12 : 0 aldehyde and/or unknown 10.953) . The major polar lipids were found to consist of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and an unidentified aminophospholipid. The predominant ubiquinone was identified as quinone 10. Based on all the above results, strain 7209-2T represents a novel species of the genus Rhizobium, for which the name Rhizobium rhizophilum sp. nov. is proposed with 7209-2T (=CGMCC 1.15691T=DSM 103161T) as the type strain.


Assuntos
Brassica napus/microbiologia , Ácidos Indolacéticos/metabolismo , Filogenia , Rhizobium/classificação , Rizosfera , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhizobium/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
16.
3 Biotech ; 10(7): 305, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32612899

RESUMO

In the present study, a new strain of Bacillus stratosphericus LW-03 was isolated from the bulbs of Lilium wardii. The isolated endophytic strain LW-03 exhibited excellent antifungal activity against common plant pathogens, such as Fusarium oxysporum, Botryosphaeria dothidea, Botrytis cinerea, and Fusarium fujikuroi. The growth inhibition percentage of Botryosphaeria dothidea was 74.56 ± 2.35%, which was the highest, followed by Botrytis cinerea, Fusarium fujikuroi, and Fusarium oxysporum were 71.91 ± 2.87%, 69.54 ± 2.73%, and 65.13 ± 1.91%, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several of which were putatively identified as antimicrobial agents, such as 4-hydroxy-2-nonenylquinoline N-oxide, sphingosine ceramides like cer(d18:0/16:0(2OH)), cer(d18:0/16:0), and cer(d18:1/0:0), di-peptides, tri-peptide, cyclopeptides [cyclo(D-Trp-L-Pro)], [cyclo (Pro-Phe)], dehydroabietylamine, oxazepam, 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine like compound (PC(0:0/20:4), phosphatidylethanolamine (PE(18:1/0:0)), 3-Hydroxyoctadecanoic acid, 7.alpha.,27-Dihydroxycholesterol, N-Acetyl-d-mannosamine, p-Hydroxyphenyllactic acid, Phytomonic acid, and 2-undecenyl-quinoloin-4 (1H). The LW-03 strain exhibits multiple plant growth-promoting traits, including the production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation activity. The beneficial effects of the endophytic strain LW-03 on the growth of two lily varieties were further evaluated under greenhouse conditions. Our results revealed plant growth-promoting activity in inoculated plants relative to non-inoculated control plants. The broad-spectrum antifungal activity and multiple plant growth-promoting properties of Bacillus stratosphericus LW-03 make it an important player in the development of biological fertilizers and sustainable agricultural biological control strategies.

17.
J Microbiol Biotechnol ; 30(5): 668-680, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32482932

RESUMO

Bacillus velezensis is an important plant growth-promoting rhizobacterium with immense potential in agriculture development. In the present study, Bacillus velezensis Lle-9 was isolated from the bulbs of Lilium leucanthum. The isolated strain showed antifungal activities against plant pathogens like Botryosphaeria dothidea, Fusarium oxysporum, Botrytis cinerea and Fusarium fujikuroi. The highest percentage of growth inhibition i.e., 68.56±2.35% was observed against Fusarium oxysporum followed by 63.12 ± 2.83%, 61.67 ± 3.39% and 55.82 ± 2.76% against Botrytis cinerea, Botryosphaeria dothidea, and Fusarium fujikuroi, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several were identified as antimicrobial agents such as diketopiperazines, cyclo-peptides, linear peptides, latrunculin A, 5α-hydroxy-6-ketocholesterol, (R)-S-lactoylglutathione, triamterene, rubiadin, moxifloxacin, 9-hydroxy-5Z,7E,11Z,14Zeicosatetraenoic acid, D-erythro-C18-Sphingosine, citrinin, and 2- arachidonoyllysophosphatidylcholine. The presence of these antimicrobial compounds in the bacterial culture might have contributed to the antifungal activities of the isolated B. velezensis Lle- 9. The strain showed plant growth-promoting traits such as production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation and phosphate solubilization. IAA production was accelerated with application of exogenous tryptophan concentrations in the medium. Further, the lily plants upon inoculation with Lle-9 exhibited improved vegetative growth, more flowering shoots and longer roots than control plants under greenhouse condition. The isolated B. velezensis strain Lle-9 possessed broad-spectrum antifungal activities and multiple plant growth-promoting traits and thus may play an important role in promoting sustainable agriculture. This strain could be developed and applied in field experiments in order to promote plant growth and control disease pathogens.


Assuntos
Antifúngicos , Bacillus , Endófitos , Lilium/microbiologia , Reguladores de Crescimento de Plantas , Antifúngicos/química , Antifúngicos/farmacologia , Bacillus/química , Bacillus/fisiologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Endófitos/química , Endófitos/fisiologia , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/farmacologia
18.
Antonie Van Leeuwenhoek ; 113(8): 1179-1189, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32468221

RESUMO

A novel 1-aminocyclopropane-1-carboxylate deaminase producing bacterium, Gram- stain-negative, aerobic, motile, rod-shaped strain designated YM1C-6-2T was isolated from rhizosphere of maize grown in Northeast China. The 16S rRNA gene sequence analysis indicated that strain YM1C-6-2T belongs to the genus Mesorhizobium and is closely related to Mesorhizobium alhagi CCNWXJ12-2T and M. camelthorni CCNWXJ40-4T with sequence similarities of 98.4% and 97.9%, respectively. Multilocus sequence analysis of other housekeeping genes revealed that the new isolates YM1C-6-2T forms a phylogenetically group with some species in the genus Mesorhizobium. The genome size of strain YM1C-6-2T was 5.51 Mb, comprising 5378 predicted genes with a DNA G+C content of 64.5%. The average nucleotide identity and digital DNA-DNA hybridization comparisons between YM1C-6-2T and the most related type strains showed values below the accepted threshold for species discrimination. The major fatty acids of strain YM1C-6-2T were C19:0 cyclo ω8c (47.5%), summed feature 8 (C18:1ω7c and/or C18:1ω6c) (19.5%) and C16:0 (15.1%), which differed from the closely related reference strains in their relative abundance. The major polar lipids consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and an unidentified aminophospholipid. The predominant ubiquinone was identified as Quinone 10. Phenotypic and biochemical analysis results indicated that strain YM1C-6-2T can be distinguished from closely related type strains. Based on the above results, strain YM1C-6-2T represents a novel species of the genus Mesorhizobium, for which the name Mesorhizobium rhizophilum sp. nov. is proposed with YM1C-6-2T (= CGMCC 1.15487T = DSM 101712T) as the type strain.


Assuntos
Carbono-Carbono Liases/biossíntese , Mesorhizobium/classificação , Mesorhizobium/enzimologia , Mesorhizobium/isolamento & purificação , Filogenia , Rizosfera , Zea mays/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Mesorhizobium/genética , Fosfatidiletanolaminas , Microbiologia do Solo , Ubiquinona/química
19.
Sci Total Environ ; 725: 138295, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32278176

RESUMO

As the world's largest CH4 emitter, China's CH4 emissions contribute to climate change more than the amount emitted by many developed countries combined. The rapid growth of China's coal demand has important implications for CH4 emissions from coal mining or coal mine methane (CMM) emissions. This paper aims to present an overview of bottom-up estimation of China's CMM emissions, including the trend in the last four decades and the limitations of current understanding on CH4 emissions. Although characterized by significant differences in inventory compilation, statistically, the total CMM emissions rose from 4.64 to 16.41 Tg with a peak of 21.48 Tg from 1980 to 2016. Large discrepancies of inventory results existed in previous studies, which were affected by the coverage of emission sources, emission factors and activity-level data. The disagreements can be largely attributable to the emission factors of underground mining, which contain substantial variances in both spatial and temporal dimensions. To develop more reliable CMM inventories and make targeted mitigation measures, more attention should be paid to the transparency of the estimated results, coal statistics, on-site CMM emission factors, and the emissions from abandoned coal mines. As the leading CH4 emission source in China, the estimations of CMM emissions urgently need to overcome existing and emerging challenges for compiling a consistent and accurate inventory.

20.
Biomed Res Int ; 2020: 8650957, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190683

RESUMO

Paenibacillus polymyxa is a plant growth-promoting rhizobacterium that has immense potential to be used as an environmentally friendly replacement of chemical fertilizers and pesticides. In the present study, Paenibacillus polymyxa SK1 was isolated from bulbs of Lilium lancifolium. The isolated endophytic strain showed antifungal activities against important plant pathogens like Botryosphaeria dothidea, Fusarium oxysporum, Botrytis cinerea, and Fusarium fujikuroi. The highest percentage of growth inhibition, i.e., 66.67 ± 2.23%, was observed for SK1 against Botryosphaeria dothidea followed by 61.19 ± 3.12%, 60.71 ± 3.53%, and 55.54 ± 2.89% against Botrytis cinerea, Fusarium fujikuroi, and Fusarium oxysporum, respectively. The metabolite profiling of ethyl acetate fraction was assessed through the UHPLC-LTQ-IT-MS/MS analysis, and putative identification was done with the aid of the GNPS molecular networking workflow. A total of 29 compounds were putatively identified which included dipeptides, tripeptides, cyclopeptides (cyclo-(Leu-Leu), cyclo(Pro-Phe)), 2-heptyl-3-hydroxy 4-quinolone, 6-oxocativic acid, anhydrobrazilic acid, 1-(5-methoxy-1H-indol-3-yl)-2-piperidin-1-ylethane-1,2-dione, octadecenoic acid, pyochelin, 15-hydroxy-5Z,8Z,11Z, 13E-eicosatetraenoic acid, (Z)-7-[(2R,3S)-3-[(2Z,5E)-Undeca-2,5-dienyl]oxiran-2-yl]hept-5-enoic acid, arginylasparagine, cholic acid, sphinganine, elaidic acid, gossypin, L-carnosine, tetrodotoxin, and ursodiol. The high antifungal activity of SK1 might be attributed to the presence of these bioactive compounds. The isolated strain SK1 showed plant growth-promoting traits such as the production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, nitrogen fixation, and phosphate solubilization. IAA production was strongly correlated with the application of exogenous tryptophan concentrations in the medium. Furthermore, inoculation of SK1 enhanced plant growth of two Lilium varieties, Tresor and White Heaven, under greenhouse condition. In the light of these findings, the P. polymyxa SK1 may be utilized as a source of plant growth promotion and disease control in sustainable agriculture.


Assuntos
Ascomicetos/fisiologia , Fusarium/fisiologia , Lilium/microbiologia , Paenibacillus polymyxa/fisiologia , Doenças das Plantas/prevenção & controle , Anti-Infecciosos/metabolismo , Carbono-Carbono Liases/metabolismo , Ácidos Carboxílicos/metabolismo , Endófitos , Ácidos Indolacéticos/metabolismo , Lilium/crescimento & desenvolvimento , Fixação de Nitrogênio , Paenibacillus polymyxa/química , Paenibacillus polymyxa/classificação , Paenibacillus polymyxa/genética , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Sideróforos/metabolismo , Espectrometria de Massas em Tandem
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