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1.
Heliyon ; 10(10): e30795, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38765039

ABSTRACT

Gustatory receptors (GRs) allow insects to sense tastes in their external environment. Gustatory perception is crucial for distinguishing between beneficial and harmful or toxic compounds, affecting survival. This study is the first to identify and classify the GR genes and investigate their expression in the predatory Arma chinensis. Thirteen GR genes (ArmaGr1-ArmaGr13) were identified and classified into four families via phylogenetic analysis. In the predacious developmental stages, ArmaGr7 expression gradually increased from the 2nd to 5th instar stages and then to adults. However, ArmaGr7 was also highly expressed in the non-predation 1st instar nymph and egg stages. ArmaGr7 expression was localized in the antennae, scalpella, forelegs, wings, head, and midgut of male and female adults, with wings displaying the highest expression. Furthermore, ArmaGr7 expression was positively correlated with fructose solution intake; molecular docking results showed that fructose could effectively dock withArmaGr7. A protein structure comparison revealed that the ArmaGr7 structure was different from that of other GR43a-like proteins, which may be related to the gene splicing of the A. chinensis GR gene. These results elucidate the crucial role of ArmaGr7 in fructose recognition by A. chinensis and provide a foundation for further studies on gustatory perception.

2.
Plant Cell Rep ; 43(3): 83, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38441719

ABSTRACT

KEY MESSAGE: The transcription factor AmCBF1 deepens the leaf colour of transgenic cotton by binding to the promoter of the chloroplast development-related protein GhClpR1 to promote photosynthesis. The ATP-dependent caseinolytic protease (Clp protease) family plays a crucial role within chloroplasts, comprising several Clp proteins to maintain chloroplast homeostasis. At present, research on Clp proteins mainly focuses on Arabidopsis, leaving its function in other plants, particularly in crops, less explored. In this study, we overexpressed AmCBF1 from Ammopiptanthus mongolicus (A. mongolicus) in wild type (R15), and found a significant darkening of leaf colour in transgenic plants (L28 and L30). RNA-seq analysis showed an enrichment of pathways associated with photosynthesis. Subsequent screening of differentially expressed genes revealed a significant up-regulation of GhClpR1, a gene linked to chloroplast development, in the transgenic strain. In addition, GhClpR1 was consistently expressed in upland cotton, with the highest expression observed in leaves. Subcellular localization analysis revealed that the protein encoded by GhClpR1 was located in chloroplasts. Yeast one hybrid and dual luciferase experiments showed that the AmCBF1 transcription factor positively regulates the expression of GhClpR1. VIGs-mediated silencing of GhClpR1 led to a significant yellowing phenotype in the leaves. This was accompanied by a reduction in chlorophyll content, and microscopic examination of chloroplast ultrastructure revealed severe developmental impairment. Finally, yeast two-hybrid assays showed that GhClpR1 interacts with the Clp protease complex accessory protein GhClpT2. Our study provides a foundation for studying the function of the Clp protease complex and a new strategy for cultivating high-light-efficiency cotton resources.


Subject(s)
Arabidopsis , Gossypium , Gossypium/genetics , Endopeptidase Clp/genetics , Chloroplasts , Photosynthesis , Arabidopsis/genetics , Transcription Factors/genetics
4.
Int J Mol Sci ; 24(20)2023 Oct 21.
Article in English | MEDLINE | ID: mdl-37895102

ABSTRACT

The original 'Green Revolution' genes are associated with gibberellin deficiency. However, in some species, mutations in these genes cause pleiotropic phenotypes, preventing their application in dwarf breeding. The development of novel genotypes with reduced plant height will resolve this problem. In a previous study, we obtained two dwarf lines, L28 and L30, by introducing the Ammopiptanthus mongolicus (Maxim. ex Kom.) Cheng f. C-repeat-binding factor 1 (AmCBF1) into the upland cotton variety R15. We found that Gossypium hirsutum Tubulin beta-1 (GhTUBB1) was downregulated in L28 and L30, which suggested that this gene may have contributed to the dwarf phenotype of L28 and L30. Here, we tested this hypothesis by silencing GhTUBB1 expression in R15 and found that decreased expression resulted in a dwarf phenotype. Interestingly, we found that repressing AmCBF1 expression in L28 and L30 partly recovered the expression of GhTUBB1. Thus, AmCBF1 expression presented a negative relationship with GhTUBB1 expression in L28 and L30. Moreover, yeast one-hybrid and dual-luciferase assays suggest that AmCBF1 negatively regulates GhTUBB1 expression by directly binding to C-repeat/dehydration-responsive (CRT/DRE) elements in the GhTUBB1 promoter, potentially explaining the dwarf phenotypes of L28 and L30. This study elucidates the regulation of GhTUBB1 expression by AmCBF1 and suggests that GhTUBB1 may be a new target gene for breeding dwarf and compact cultivars.


Subject(s)
Gossypium , Tubulin , Gossypium/metabolism , Tubulin/metabolism , Plant Breeding , Phenotype , Genotype , Gene Expression Regulation, Plant , Plant Proteins/genetics , Plant Proteins/metabolism
5.
Nat Commun ; 14(1): 3857, 2023 06 29.
Article in English | MEDLINE | ID: mdl-37385996

ABSTRACT

Phytopathogenic fungi secrete chitin deacetylase (CDA) to escape the host's immunological defense during infection. Here, we showed that the deacetylation activity of CDA toward chitin is essential for fungal virulence. Five crystal structures of two representative and phylogenetically distant phytopathogenic fungal CDAs, VdPDA1 from Verticillium dahliae and Pst_13661 from Puccinia striiformis f. sp. tritici, were obtained in ligand-free and inhibitor-bound forms. These structures suggested that both CDAs have an identical substrate-binding pocket and an Asp-His-His triad for coordinating a transition metal ion. Based on the structural identities, four compounds with a benzohydroxamic acid (BHA) moiety were obtained as phytopathogenic fungal CDA inhibitors. BHA exhibited high effectiveness in attenuating fungal diseases in wheat, soybean, and cotton. Our findings revealed that phytopathogenic fungal CDAs share common structural features, and provided BHA as a lead compound for the design of CDA inhibitors aimed at attenuating crop fungal diseases.


Subject(s)
Inhibition, Psychological , Mycoses , Humans , Amidohydrolases , Chitin , Cladribine , Cytidine Deaminase
6.
Genes (Basel) ; 14(5)2023 04 27.
Article in English | MEDLINE | ID: mdl-37239353

ABSTRACT

Cohesin is a ring-shaped protein complex and plays a critical role in sister chromosome cohesion, which is a key event during mitosis and meiosis. Meiotic recombination protein REC8 is one of the subunits of the cohesion complex. Although REC8 genes have been characterized in some plant species, little is known about them in Gossypium. In this study, 89 REC8 genes were identified and analyzed in 16 plant species (including 4 Gossypium species); 12 REC8 genes were identified in Gossypium. hirsutum, 11 in Gossypium. barbadense, 7 in Gossypium. raimondii, and 5 in Gossypium. arboreum. In a phylogenetic analysis, the 89 RCE8 genes clustered into 6 subfamilies (I-VI). The chromosome location, exon-intron structure, and motifs of the REC8 genes in the Gossypium species were also analyzed. Expression patterns of GhREC8 genes in various tissues and under abiotic stress treatments were analyzed based on public RNA-seq data, which indicated that GhREC8 genes might have different functions in growth and development. Additionally, qRT-PCR analysis showed that MeJA, GA, SA, and ABA treatments could induce the expression of GhREC8 genes. In general, the genes of the REC8 gene family of cotton were systematically analyzed, and their potential function in cotton mitosis, meiosis, and in response to abiotic stress and hormones were preliminary predicted, which provided an important basis for further research on cotton development and resistance to abiotic stress.


Subject(s)
Gossypium , Gossypium/genetics , Genome, Plant , Plant Proteins/genetics , Phylogeny , Chromosomes, Plant , Stress, Physiological
7.
PeerJ ; 11: e15338, 2023.
Article in English | MEDLINE | ID: mdl-37168534

ABSTRACT

Background: DNA metabarcoding is rapidly emerging as a cost-effective approach for large-scale biodiversity assessment and pest monitoring. The current study employed metabarcoding to assess insect diversity in citrus orchards in Ganzhou City, Jiangxi, China in both 2018 and 2019. Insects were sampled using Malaise traps deployed in three citrus orchards producing a total of 43 pooled monthly samples. Methods: The Malaise trap samples were sequenced following DNA metabarcoding workflow. Generated sequences were curated and analyzed using two cloud databases and analytical platforms, the barcode of life data system (BOLD) and multiplex barcode research and visualization environment (mBRAVE). Results: These platforms assigned the sequences to 2,141 barcode index numbers (BINs), a species proxy. Most (63%) of the BINs were shared among the three sampling sites while BIN sharing between any two sites did not exceed 71%. Shannon diversity index (H') showed a similar pattern of BIN assortment at the three sampling sites. Beta diversity analysis by Jaccard similarity coefficient (J) and Bray-Curtis distance matrix (BC) revealed a high level of BIN similarity among the three sites (J = 0.67-0.68; BC = 0.19-0.20). Comparison of BIN records against all those on BOLD made it possible to identify 40% of the BINs to a species, 57% to a genus, 97% to a family and 99% to an order. BINs which received a species match on BOLD were placed in one of four categories based on this assignment: pest, parasitoid, predator, or pollinator. As this study provides the first baseline data on insect biodiversity in Chinese citrus plantations, it is a valuable resource for research in a broad range of areas such as pest management and monitoring beneficial insects in citrus gardens.


Subject(s)
Citrus , Moths , Animals , DNA Barcoding, Taxonomic , Citrus/genetics , Insecta/genetics , Moths/genetics , Biodiversity , DNA/genetics
8.
Int J Biol Macromol ; 239: 124354, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37028625

ABSTRACT

No effective fungicides are available for the management of Verticillium dahliae, which causes vascular wilt disease. In this study, a star polycation (SPc)-based nanodelivery system was used for the first time to develop a thiophanate-methyl (TM) nanoagent for the management of V. dahliae. SPc spontaneously assembled with TM through hydrogen bonding and Van der Waals forces to decrease the particle size of TM from 834 to 86 nm. Compared to TM alone, the SPc-loaded TM further reduced the colony diameter of V. dahliae to 1.12 and 0.64 cm, and the spore number to 1.13 × 108 and 0.72 × 108 cfu/mL at the concentrations of 3.77 and 4.71 mg/L, respectively. The TM nanoagents disturbed the expression of various crucial genes in V. dahliae, and contributed to preventing plant cell-wall degradation and carbon utilization by V. dahliae, which mainly impaired the infective interaction between pathogens and plants. TM nanoagents remarkably decreased the plant disease index and the fungal biomass in the root compared to TM alone, and its control efficacy was the best (61.20 %) among the various formulations tested in the field. Furthermore, SPc showed negligible acute toxicity toward cotton seeds. To the best of our knowledge, this study is the first to design a self-assembled nanofungicide that efficiently inhibits V. dahliae growth and protects cotton from the destructive Verticillium wilt.


Subject(s)
Ascomycota , Thiophanate , Plant Cells , Ascomycota/metabolism , Carbon/pharmacology , Carbon/metabolism , Gossypium/metabolism , Plant Diseases/microbiology , Disease Resistance/genetics , Plant Proteins/genetics , Gene Expression Regulation, Plant
9.
Int J Mol Sci ; 24(3)2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36768168

ABSTRACT

Heat shock transcription factors (HSFs) play a critical regulatory role in many plant disease resistance pathways. However, the molecular mechanisms of cotton HSFs involved in resistance to the soil-borne fungus Verticillium dahliae are limited. In our previous study, we identified numerous differentially expressed genes (DEGs) in the transcriptome and metabolome of V. dahliae-inoculated Arabidopsis thaliana. In this study, we identified and functionally characterized GhHSFB2a, which is a DEG belonging to HSFs and related to cotton immunity to V. dahliae. Subsequently, the phylogenetic tree of the type two of the HSFB subfamily in different species was divided into two subgroups: A. thaliana and strawberry, which have the closest evolutionary relationship to cotton. We performed promoter cis-element analysis and showed that the defense-reaction-associated cis-acting element-FC-rich motif may be involved in the plant response to V. dahliae in cotton. The expression pattern analysis of GhHSFB2a displayed that it is transcriptional in roots, stems, and leaves and significantly higher at 12 h post-inoculation (hpi). Subcellular localization of GhHSFB2a was observed, and the results showed localization to the nucleus. Virus-induced gene silencing (VIGS) analysis exhibited that GhHSFB2a silencing increased the disease index and fungal biomass and attenuated resistance against V. dahliae. Transcriptome sequencing of wild-type and GhHSFB2a-silenced plants, followed by Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, protein-protein interaction, and validation of marker genes revealed that ABA, ethylene, linoleic acid, and phenylpropanoid pathways are involved in GhHSFB2a-mediated plant disease resistance. Ectopic overexpression of the GhHSFB2a gene in Arabidopsis showed a significant increase in the disease resistance. Cumulatively, our results suggest that GhHSFB2a is required for the cotton immune response against V. dahliae-mediated ABA, ethylene, linoleic acid, and phenylpropanoid pathways, indicating its potential role in the molecular design breeding of plants.


Subject(s)
Ascomycota , Verticillium , Heat Shock Transcription Factors/genetics , Disease Resistance/genetics , Linoleic Acid , Phylogeny , Verticillium/physiology , Ascomycota/metabolism , Gossypium/genetics , Gossypium/metabolism , Plant Diseases/microbiology , Gene Expression Regulation, Plant , Plant Proteins/metabolism
10.
Sci Rep ; 12(1): 18749, 2022 11 05.
Article in English | MEDLINE | ID: mdl-36335196

ABSTRACT

There is a high rate of recurrent hypertriglyceridemic acute pancreatitis (HTG-RAP) and risk of developing into chronic pancreatitis among recurrent hypertriglyceridemic acute pancreatitis. The key to avoiding recurrence is home-based self-management. However, self-management has proven to be difficult. Exploring experiences and perceptions of home-based self-management among patients with HTG-RAP could inform intervention development and policy making in primary care. To explore experiences and perceptions of home-based self-management among patients with HTG-RAP. This is primarily a qualitative study involving patients from eastern China. The study was designed using semi-structured interviews combined with open interviews among individuals and focus groups. Interviews with patients (n = 25) and relatives (n = 2) were conducted from October to December, 2021. Data were analyzed using the thematic analysis approach. Five themes were identified: (1) pity, (2) sense of uncertainty, (3) contradiction, (4) the way to cope, and (5) benefits. The themes constituted a continuous process where a final coping strategy was confirmed. Patients expressed sorrow, struggle, pity, adaptation, and benefits. The disease still bothered them without attack, both mentally and physically. These key points deserve considerable attention to improve the quality of life of patients and lifestyle modification. Patients with pancreatitis were more likely to manage the disease but under a tough process, and during the struggle, they experienced a continuous and contradictory period. Ultimately, the final condition was reached.


Subject(s)
Pancreatitis, Chronic , Quality of Life , Humans , Acute Disease , Qualitative Research , Pancreatitis, Chronic/therapy
11.
Front Plant Sci ; 13: 1050216, 2022.
Article in English | MEDLINE | ID: mdl-36407619

ABSTRACT

Heat shock factors (HSFs) play a crucial role in the environmental stress responses of numerous plant species, including defense responses to pathogens; however, their role in cotton resistance to Verticillium dahliae remains unclear. We have previously identified several differentially expressed genes (DEGs) in Arabidopsis thaliana after inoculation with V. dahliae. Here, we discovered that GhHSFA4a in Gossypium hirsutum (cotton) after inoculation with V. dahliae shares a high identity with a DEG in A. thaliana in response to V. dahliae infection. Quantitative real-time PCR (qRT-PCR) analysis indicated that GhHSFA4a expression was rapidly induced by V. dahliae and ubiquitous in cotton roots, stems, and leaves. In a localization analysis using transient expression, GhHSFA4a was shown to be localized to the nucleus. Virus-induced gene silencing (VIGS) revealed that downregulation of GhHSFA4a significantly increased cotton susceptibility to V. dahliae. To investigate GhHSFA4a-mediated defense, 814 DEGs were identified between GhHSFA4a-silenced plants and controls using comparative RNA-seq analysis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs were enriched in "flavonoid biosynthesis", "sesquiterpenoid and triterpenoid biosynthesis", "linoleic acid metabolism" and "alpha-linolenic acid metabolism". The expression levels of marker genes for these four pathways were triggered after inoculation with V. dahliae. Moreover, GhHSFA4a-overexpressing lines of A. thaliana displayed enhanced resistance against V. dahliae compared to that of the wild type. These results indicate that GhHSFA4a is involved in the synthesis of secondary metabolites and signal transduction, which are indispensable for innate immunity against V. dahliae in cotton.

12.
Nanotechnology ; 34(1)2022 Oct 12.
Article in English | MEDLINE | ID: mdl-36150363

ABSTRACT

The establishment of heterojunction is a powerful strategy to enhance the photoresponse performance of photoanode. Here, TiO2/CuInS2(T/CIS) composites were prepared via a two-step hydrothermal method, and their morphologies were controlled by adjusting the reaction time. The absorption spectra show that CuInS2can significantly improve the absorption of visible light. The T/CIS2 (2 h reaction time) photoanode exhibited the most outstanding photoelectrochemical (PEC) performance, with a photocurrent density of 168% that of the pure TiO2photoanode. Under simulated sunlight, this photoanode can supply a protective photocurrent of 0.49 mA cm-2and a protective voltage of 0.36 V to stainless steel (304ss), which are about 4 and 2 times those of the TiO2sample. The enhancement in the photocathodic protection performance is attributed to enlarged visible light absorbance and higher charge separation rate. This study demonstrates that the TiO2/CuInS2photoanode is a promising candidate for application in photoinduced cathodic protection of metallic materials.

13.
Front Plant Sci ; 13: 914206, 2022.
Article in English | MEDLINE | ID: mdl-35712572

ABSTRACT

Dwarfism is a beneficial trait in many crops. Dwarf crops hold certain advantages over taller crops in lodging resistance, fertilizer tolerance, and yield. Overexpression of CBF/DREB transcription factors can lead to dwarfing in many plant species, but the molecular mechanism of plant dwarfing caused by overexpression of CBF/DREB in upland cotton (Gossypium hirsutum) remains unclear. In this study, we observed that overexpression of the Ammopiptanthus mongolicus AmCBF1 transcription factor in upland cotton R15 reduced plant height, whereas virus-induced gene silencing of AmCBF1 in the derived dwarf lines L28 and L30 partially restored plant height. Five protein phosphatase (PP2C) genes (GhPP2C1 to GhPP2C5) in cotton were identified by RNA-sequencing among genes differentially expressed in L28 or L30 in comparison with R15 and thus may play an important role in AmCBF1-regulated dwarfing in cotton. Gene expression analysis showed that the GhPP2C genes were down-regulated significantly in L28 and L30, and silencing of GhPP2C1 or GhPP2C2 in R15 inhibited the growth of cotton seedlings. Subcellular localization assays revealed that GhPP2C1 was localized to the cell membrane and nucleus, whereas GhPP2C2 was exclusively localized to the nucleus. Yeast one-hybrid and dual-luciferase assays showed that AmCBF1 was able to bind to the CRT/DRE elements of the upstream promoter of GhPP2C1 or GhPP2C2 and repress their expression. These findings provide insight into the mechanism of dwarfing and may contribute to the breeding of dwarf cultivars of upland cotton.

14.
PeerJ ; 10: e13422, 2022.
Article in English | MEDLINE | ID: mdl-35637712

ABSTRACT

China's main cotton production area is located in the northwest where abiotic stresses, particularly cold and drought, have serious effects on cotton production. In this study, Ammopiptanthus mongolicus C-repeat-binding factor (AmCBF1) isolated from the shrub Ammopiptanthus mongolicus was inserted into upland cotton (Gossypium hirsutum L.) cultivar R15 to evaluate the potential benefits of this gene. Two transgenic lines were selected, and the transgene insertion site was identified using whole-genome sequencing. The results showed that AmCBF1 was incorporated into the cotton genome as a single copy. Transgenic plants had distinctly higher relative water content (RWC), chlorophyll content, soluble sugar content, and lower ion leakage than R15 after drought and cold stress. Some characteristics, such as the area of lower epidermal cells, stomatal density, and root to shoot ratio, varied significantly between transgenic cotton lines and R15. Although the photosynthetic ability of transgenic plants was inhibited after stress, the net photosynthetic rate, stomatal conductance, and transpiration rate in transgenic plants were significantly higher than in R15. This suggested that an enhanced stress tolerance and photosynthesis of transgenic cotton was achieved by overexpressing AmCBF1. All together, our results demonstrate that the new transgenic cotton germplasm has great application value against abiotic stresses, especially in the northwest inland area of China.


Subject(s)
Cold-Shock Response , Gossypium , Gossypium/genetics , Droughts , Plants, Genetically Modified/genetics , Photosynthesis/genetics
15.
Mult Scler Relat Disord ; 59: 103544, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35092947

ABSTRACT

BACKGROUND: Involvement of the central gray matter of spinal cord is a characteristic magnetic resonance imaging (MRI) feature of aquaporin-4-immunoglobulin G antibodies (AQP4-IgG) positive neuromyelitis optica spectrum disorders (NMOSD). However, there has been no systemic electrophysiological study investigating the frequency of lower motor neuron involvement in NMOSD patients. METHODS: We retrospectively reviewed a cohort of 59 NMOSD patients with results of concentric needle electromyography (EMG) and nerve conduction studies (NCS) that were admitted to the Department of Neurology of Chinese PLA General Hospital between January 2016 and December 2019. RESULTS: Acute and/or chronic denervation was found in 22.0% (13/59) of the NMOSD patients by EMG. Peripheral or cranial neuropathy indicated by abnormal NCS changes was found in 11.9% (7/59) of the NMOSD patients. Denervation indicated by EMG that can be accounted for by abnormal NCS was found in 6.8% (4/59) of the NMOSD patients, while 3.4% (2/59) of the NMOSD patients had NCS abnormality without denervation indicated by EMG. Accordingly, 9 of the 59 NMOSD patients (15.3%) had lower motor neuron involvement, and moreover, 6.8% (4/59) of the NMOSD patients had corresponding spinal cord or brainstem lesions on MRI. CONCLUSION: Not uncommon lower motor neuron involvement exists in NMOSD patients, so needle EMG and NCS studies should be performed in NMOSD patients with suspected lower motor neuron involvement.


Subject(s)
Neuromyelitis Optica , Aquaporin 4 , Autoantibodies , Humans , Motor Neurons/pathology , Retrospective Studies
17.
Front Plant Sci ; 13: 1059404, 2022.
Article in English | MEDLINE | ID: mdl-36643290

ABSTRACT

CRIPSR/Cas9 gene editing system is an effective tool for genome modification in plants. Multiple target sites are usually designed and the effective target sites are selected for editing. Upland cotton (Gossypium hirsutum L., hereafter cotton) is allotetraploid and is commonly considered as difficult and inefficient to transform, it is important to select the effective target sites that could result in the ideal transgenic plants with the CRISPR-induced mutations. In this study, Agrobacterium rhizogenes-mediated hairy root method was optimized to detect the feasibility of the target sites designed in cotton phytoene desaturase (GhPDS) gene. A. rhizogenes showed the highest hairy root induction (30%) when the bacteria were cultured until OD600 reached to 0.8. This procedure was successfully applied to induce hairy roots in the other three cultivars (TM-1, Lumian-21, Zhongmian-49) and the mutations were detected in GhPDS induced by CRISPR/Cas9 system. Different degrees of base deletions at two sgRNAs (sgRNA5 and sgRNA10) designed in GhPDS were detected in R15 hairy roots. Furthermore, we obtained an albino transgenic cotton seeding containing CRISPR/Cas9-induced gene editing mutations in sgRNA10. The hairy root transformation system established in this study is sufficient for selecting sgRNAs in cotton, providing a technical basis for functional genomics research of cotton.

18.
Cells ; 10(12)2021 12 20.
Article in English | MEDLINE | ID: mdl-34944096

ABSTRACT

As an ecofriendly biocontrol agent, antagonistic bacteria are a crucial class of highly efficient fungicides in the field against Verticillium dahliae, the most virulent pathogen for cotton and other crops. Toward identifying urgently needed bacterial candidates, we screened bacteria isolated from the cotton rhizosphere soil for antagonisitic activity against V. dahliae in an artificially infested nursery. In preliminary tests of antagonistic candidates to characterize the mechanism of action of on culture medium, 88 strains that mainly belonged to Bacillus strongly inhibited the colony diameter of V. dahliae, with inhibiting efficacy up to 50% in 9 strains. Among the most-effective bacterial strains, Bacillus sp. ABLF-18, and ABLF-50 and Paenibacillus sp. ABLF-90 significantly reduced the disease index and fungal biomass of cotton to 40-70% that of the control. In further tests to elucidate the biocontrol mechanism (s), the strains secreted extracellular enzymes cellulase, glucanase, and protease, which can degrade the mycelium, and antimicrobial lipopeptides such as surfactin and iturin homologues. The expression of PAL, MAPK and PR10, genes related to disease resistance, was also elicited in cotton plants. Our results clearly show that three candidate bacterial strains can enhance cotton defense responses against V. dahliae; the secretion of fungal cell-wall-degrading enzymes, synthesis of nonribosomal antimicrobial peptides and induction of systemic resistance shows that the strains have great potential as biocontrol fungicides.


Subject(s)
Ascomycota/physiology , Bacteria/isolation & purification , Gossypium/microbiology , Plant Diseases/microbiology , Disease Resistance/genetics , Extracellular Space/enzymology , Gene Expression Regulation, Plant , Gossypium/genetics , Lipopeptides/metabolism , Pest Control, Biological , Phylogeny , Plant Diseases/genetics
19.
Sheng Wu Gong Cheng Xue Bao ; 37(7): 2463-2473, 2021 Jul 25.
Article in Chinese | MEDLINE | ID: mdl-34327911

ABSTRACT

The hydroponic culture test method was used to study the physiological and biochemical responses of Paulownia fortunei seedlings under Zn stress, Cd stress, and combined Zn and Cd stress as well as changes in the enrichment and transfer characteristics of heavy metals. Under single and combined heavy metal stress, the biomass, plant height, and peroxidase (POD) activity of P. fortunei decreased as the treatment concentration increased. Combined Zn and Cd affected adversely plant height and biomass. As the concentration of Zn increased when applied alone, the chlorophyll content and catalase (CAT) activity of P. fortunei first increased and then decreased, the superoxide dismutase (SOD) activity increased, and the aboveground malondialdehyde (MDA) content first decreased and then increased. As the concentration of Cd increased when applied alone, chlorophyll content and CAT activity increased, and SOD activity and aboveground MDA content first increased and then decreased. Under both Cd and Zn, the physiological response was more complex. Cd in the seedlings of P. fortunei was concentrated in the root. In contrast, Zn was concentrated in the upper part of the ground, and its transfer coefficient was greater than 1.00. Thus, the addition of Zn promotes the transfer of heavy metals to the above-ground portions of plants. Generally, P. fortunei can effectively promote ecological restoration under complex forms of heavy metal pollution.


Subject(s)
Metals, Heavy , Soil Pollutants , Cadmium , Chlorophyll , Plant Roots/chemistry , Seedlings , Stress, Physiological , Superoxide Dismutase , Zinc
20.
ChemSusChem ; 13(19): 5264-5272, 2020 Oct 07.
Article in English | MEDLINE | ID: mdl-32681615

ABSTRACT

Co/MII Fe layered double hydroxide (LDH) LDH photocatalysts have been designed from the aspect of employing stable half-filled Fe3+ to trap photogenerated electrons, adjusting the MII -O-Fe oxo-bridged structure to optimize the short-range directional charge transmission and intercalating oxometallate anions into the LDH to further improve light absorption along with electron-hole separation and non-noble metal Co NP loading and reduction to form a heterojunction. These LDH-based photocatalysts are employed for photocatalytic H2 evolution from ammonia borane in aqueous solution under visible light at 298 K. The photocatalytic H2 evolution activity is greatly improved through adjustment of the MII -O-Fe oxo-bridged structure and molybdate intercalation into the LDH. Turnover frequencies of up to 113.2 min-1 are achieved with Co/CoFe-Mo. Alongside the experimental results and materials characterization, capture experiments and in situ DRIFTS analysis are carried out to study the photocatalytic hydrogen production mechanism.

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