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In the present study, the efficiency of the biocontrol agent Paenibacillus alvei (strain K165) to suppress Verticillium wilt of olive tree was evaluated in greenhouse and field experiments. In planta bioassays were conducted under greenhouse conditions and revealed that K165 significantly decreased symptoms on the susceptible cultivar ‘Amfissis’ by 44.5 and 51.6 % of the final disease severity index and relative area under disease progress curve (AUDPC), respectively. Thereafter, the suppressive effect of K165 against Verticillium dahliae was studied for two consecutive years (2007 and 2008) in a newly established olive orchard of the susceptible cv Amfissis and the resistant cv Kalamon, naturally infested with V. dahliae. The evaluation of K165 was carried out by recording symptoms, isolations and qPCR quantification of the pathogen in olive tissues. In both years, ‘Amfissis’ trees treated with K165 showed significantly lower final disease severity and relative AUDPC values compared to the non treated controls, whereas, in 2008 decreased symptom severity was associated with significantly lower V. dahliae DNA levels in plant tissues, indicating the suppressive effect of the biocontrol agent. However, no significant suppression was observed in ‘Kalamon’. Pathogen isolations along with qPCR quantification revealed a seasonal fluctuation of V. dahliae biomass in olive tissues with higher amounts occurring in May, and lower amounts in February, August and November. This is the first report of biological control of Verticillium wilt of olive tree under field conditions, associated with reduced pathogen levels inside the xylem tissues.  相似文献   

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Verticillium wilt (V. wilt), a notorious wilt disease caused by Verticillium dahliae, often leads to the reduction of eggplant (Solanum melongena L.) production. MiRNAs, as a class of small RNAs, can regulate gene expression and then affect growth and development in plants. MiR395 has been proven to respond to sulfate-deficient stress in Arabidopsis thaliana and sulfate is well known to have a close relationship with plant disease resistance. To explore the function of eggplant miR395, we examined its expression in V. dahliae-infected eggplant by qRT-PCR and found miR395 exhibited a gradual reduction trend with time after infection. We then expressed pre-miR395 from Arabidopsis thaliana in Suqi eggplant and resistance analysis showed that miR395 overexpressed plants were hypersensitive to V. dahliae infection. We further measured the content of GSH and activities of POD and SOD and the results indicated that the index of GSH/POD/SOD in the overexpressed plants was lower than that of the wild-type control under V. dahliae infection. These results suggest that miR395 plays a negative role in eggplant response to V. dahliae infection.  相似文献   

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In this study, we comparatively analyzed the 115 Hsp70 genes identified in Gossypium raimondii, Gossypium hirsutum and Gossypium arboreum genomes. Those Hsp70 genes unequally distributed among chromosomes in A and D genome of cotton (Gossypium spp.), and were classified into 29 groups according to the homology of them. Based on the localization information of the orthologs in Arabidopsis, the Hsp70 proteins were predicted to locate in cytosol, endoplasmic reticulum, mitochondrion or chloroplast. Homologous analysis indicated the evolutionary conservation of Hsp70 in cotton. In addition, those Hsp70 genes were differently expressed in Suyuan-045, Hai-7124 and TM-1, which were highly resistant, resistant, and sensitive to Verticillium dahliae respectively. The expressions of 26 Hsp70 genes were induced by Verticillium dahliae except for Hsp70-07/16/25/26, and the result suggested the potential involvement of them in responding to Verticillium wilt. Hsp70-08/30/31 was highly expressed in both Suyuan-045 and Hai-7124, and it was hypothesized that they might be involved in the resistance to the invasion of Verticillium dahliae. 144h after inoculation with Verticillium dahliae, the expression of Hsp70-13/14/15 was only up-regulated in Suyuan-045, and it was assumed that they might be involved in resistance to the extension of Verticillium dahliae. Further study on those Hsp70 genes would be valuable to reveal the role of them in Verticillium wilt resistance.  相似文献   

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Anthocyanins are secondary metabolites that play important roles in plant adaption to adverse environments. The anthocyanin biosynthetic pathway is conserved in high plants. Previous studies revealed the significant role of anthocyanins in natural-colorized cotton. However, little is known about the involvement of anthocyanins in the interaction of cotton and pathogen. In this study, a pathogen-induced gene was isolated from Gossypium barbadense that encodes an anthocyanidin synthase protein (GbANS) with dioxygenase structures. GbANS was preferentially expressed in colored tissue. Silencing of GbANS significantly reduced the production of anthocyanins, as well as the cotton’s resistance to Verticillium dahliae. Biochemical studies revealed that GbANS-silenced cotton accumulated more hydrogen peroxide compared to control plants during the V. dahliae invasion process. This accumulation of hydrogen peroxide corresponded with increased cell death around the invasion sites, which in turn accelerated the V. dahliae infection. Taken together, we found that GbANS contributes to the biosynthesis of anthocyanins in cotton and anthocyanins positively regulate cotton’s resistance to V. dahliae.  相似文献   

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Vascular wilt pathogens, like Fusarium oxysporum and Verticillium dahliae, cause heavy economic loses to a range of crops. The lack of chemical control intensifies the problem. In the present study, the initial in vitro activity of 134 bacterial isolates, originating from various stages of the composting process of cotton residues, against F. oxysporum f. sp. melonis (FOM) and V. dahliae was evaluated. The most efficient strains, named SP10 and C20 M, belong to Bacillus sp. Both strains significantly reduced Fusarium and Vertilicillium wilt in melon and aubergine respectively. Furthermore, zeolite was tested alone or in combination with SP10 against V. dahliae and FOM. It was shown that the combination of zeolite and SP10 in the transplant soil plug was the most disease suppressive treatment. Interestingly the single application of zeolite was also plant-protective. The positive effect of zeolite on plant health could be linked with the recorded up-regulation of plant defense genes.  相似文献   

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Verticillium wilt (Verticillium dahliae) is an economically important disease for many high-value crops. The pathogen is difficult to manage due to the long viability of its resting structures, wide host range, and the inability of fungicides to affect the pathogen once in the plant vascular system. In chile pepper (Capsicum annuum), breeding for resistance to Verticillium wilt is especially challenging due to the limited resistance sources. The dominant Ve locus in tomato (Solanum lycopersicum) contains two closely linked and inversely oriented genes, Ve1 and Ve2. Homologs of Ve1 have been characterized in diverse plant species, and interfamily transfer of Ve1 confers race-specific resistance. Queries in the chile pepper WGS database in NCBI with Ve1 and Ve2 sequences identified one open reading frame (ORF) with homology to the tomato Ve genes. Comparison of the candidate CaVe (Capsicum annuum Ve) gene sequences from susceptible and resistant accessions revealed 16 single nucleotide polymorphisms (SNPs) and several haplotypes. A homozygous haplotype was identified for the susceptible accessions and for resistant accessions. We developed a cleaved amplified polymorphic sequence (CAPS) molecular marker within the coding region of CaVe and screened diverse germplasm that has been previously reported as being resistant to Verticillium wilt in other regions. Based on our phenotyping using the New Mexico V. dahliae isolate, the marker could select resistance accessions with 48% accuracy. This molecular marker is a promising tool towards marker-assisted selection for Verticillium wilt resistance and has the potential to improve the efficacy of chile pepper breeding programs, but does not eliminate the need for a bioassay. Furthermore, this work provides a basis for future research in this important pathosystem.  相似文献   

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Background

The relationship between cognitive assessment results in multiple sclerosis (MS) and performance in daily activities (DAs) remains unclear. Our study aimed to evaluate the relationship between cognitive functions (CF) measured by tests, performance in DAs, and the perception of CF in patients and their caregivers (CG) in MS.

Methods

The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) battery was used to evaluate cognitive status. We created an ad hoc questionnaire (DaQ) to assess performance in DAs not requiring specific motor skills. We used the Multiple Sclerosis Neuropsychological Questionnaire (MSNQ) to measure each patient self-judgment and caregiver’s perception of CF.

Results

Forty-nine patients and their caregivers were included in the study. Significant correlations were found between the BICAMS and the DaQ (Symbol Digit Modalities Test (SDMT): r?=???0.48, p?<?0.001; California Verbal Learning Test (CVLT): r?=???0.33, p?=?0.01; Brief Visual Memory Test (BVMT-R): r?=???0.42; p?=?0.002); patients self-judgment (SDMT: r?=???0.38, p?=?0.004; CVLT: r?=???0.26, p?=?0.03); caregiver perception of patient’s CF (SDMT: r?=???0.52, p?<?0.001; CVLT: r?=???0.3, p?=?0.01; BVMT-R: r?=???0.42, p?=?0.002). The difference in perception between the patients and their caregivers was related to patient age (p?=?0.001) and severity of cognitive impairment (p?=?0.03).

Conclusions

Cognitive assessment results show a significant correlation with performance in daily activities and with patients and, especially, caregiver perception of cognitive impairment. These data support the importance of a routine evaluation of cognitive function in MS that includes an anamnestic evaluation of patients, and, when possible, consideration of the caregiver’s point of view.
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14.
Human toxocarosis is one of the most widespread and prevalent helminthic zoonosis in many countries, including Slovakia. The aim was to evaluate the usefulness of IgA anti-Toxocara antibody detection in the serodiagnosis of toxocarosis. The levels of specific IgA antibodies were determined by excretory-secretory (ES)-enzyme-linked immunosorbent assay (ELISA). The IgA seropositivity in IgG anti-Toxocara seropositive patients (n?=?52) was 32.7% and found to be highest in the oldest age groups (P?=?0.026). The presence of IgA in suspected patients for toxocarosis were evaluated in respect to some characteristics of examined persons. Substantially higher IgA seropositivity was detected in patients with increased total IgE (44.8%) than in subjects with a normal level of IgE (17.4%; P?=?0.036). No associations (P?>?0.05) were found between IgA seropositivity and sex, level of specific IgG antibodies, avidity of IgG, eosinophilia, domicile, geophagia, traveling abroad, dog/cat ownership, or clinical symptoms. The IgA-ELISA showed sensitivity of 57.1% and specificity of 100%. Mild correlations (r?=?0.302, r?=?0.305, r?=???0.409) were observed between the levels of anti-Toxocara IgA antibodies and age, the amounts of eosinophils and IgA antibody levels, the amounts of eosinophils, and the values of IgG avidity, respectively. The presence of anti-Toxocara IgA may facilitate the diagnosis of toxocarosis and may well be useful for the determination of acute Toxocara infection. Moreover, this test should be accompanied by other immunological markers of examined patients (e.g., increased total IgE, eosinophilia, and low-avidity IgG antibodies).  相似文献   

15.
A complex of Ag/AgCl nanoparticles was synthesized on the basis of the extracellular polysaccharide of Azotobacter chroococcum XU1 and 10 mM AgNO3 solution. The complex was characterized by UV spectroscopy, X-ray diffraction, and scanning electron microscopy. Colloidal solutions of the complex had absorption peaks at 260 and 420 nm, indicating the formation Ag/AgCl nanoparticles. The size of the nanoparticles varied from 6 to 50 nm. The nanobiocomposite consisting of the exopolysaccharide matrix and Ag/AgCl nanoparticles exhibited a fungicidal effect against such plant pathogens as Fusarium oxysporum f. sp. vasinfectum and Verticillium dahliae.  相似文献   

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A simple and green method was developed for the extracellular biosynthesis of silver chloride nanoparticles, free from silver nanoparticles, using cell-free filtrate of a thermotolerant fungal strain Aspergillus terreus 8. The synthesized silver chloride nanoparticles exhibited characteristic absorption maximum at 275 nm. As-fabricated AgCl-NPs were characterized by UV-vis spectroscopy, XRD, SEM-EDX, and FT-IR. The biosynthesized silver chloride nanoparticles exhibited strong antimicrobial activity towards pathogenic microorganisms such as Fusarium oxysporum f. sp. vasinfectum and Verticillium dahliae. The synthesized silver chloride nanoparticles can be exploited as a promising new biocide bionanocomposite against pathogenic microorganisms.  相似文献   

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Natural polymorphisms at the foraging (for) gene influence several behaviors. However, it is seldom clear how different for alleles could be selected. In one case, Drosophila with the rover allele (for r ) have higher locomotor activity in the presence of food than animals with the sitter allele (for s ), suggesting a complementary feeding strategy. There are, in addition, differences between for r and for s Drosophila in some tests of short-term memory (for r animals generally perform at higher levels) and thermotolerance (for s larvae are more resistant to the effects of high-temperature). We asked whether there could be a direct compensating advantages in adult for s flies that could maintain the natural for variants. First, are adult for s flies more thermotolerant? Second, do for r flies have a higher short-term place memory? Third, as an alternative, might for s flies have higher place memory? Our results do not confirm these possibilities. Thus, a thermotolerance advantage of for s flies does not compensate for a potential for r short-term memory advantage; for r flies do not have a universal advantage in short-term memory; and for s flies do not have an advantage in place memory that could compensate for for r advantages in other learning contexts.  相似文献   

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The aim of present study was to elucidate the association of CTLA4 +49 A/G and HLA-DRB1*/DQB1* gene polymorphism in south Indian T1DM patients. The patients and controls (n?=?196 each) were enrolled for CTLA4 and HLA-DRB1*/DQB1* genotyping by RFLP/PCR-SSP methods. The increased frequencies of CTLA4 ‘AG’ (OR?=?1.99; p?=?0.001), ‘GG’ (OR?=?3.94; p?=?0.001) genotypes, and ‘G’ allele (OR?=?2.42; p?=?9.26?×?10?8) were observed in patients. Reduced frequencies of ‘AA’ (OR?=?0.35; p?=?7.19?×?10?7) and ‘A’ (OR?=?0.41; p?=?9.26?×?10?8) in patients revealed protective association. Among HLA-DRB1*/DQB1* alleles, DRB1*04 (OR?=?3.29; p?=?1.0?×?10?5), DRB1*03 (OR?=?2.81; p?=?1.9?×?10?6), DQB1*02:01 (OR?=?2.93; p?=?1.65?×?10?5), DQB1*02:02 (OR?=?3.38; p?=?0.0003), and DQB1*03:02 (OR?=?7.72; p?=?0.0003) were in susceptible association. Decreased frequencies of alleles, DRB1*15 (OR?=?0.32; p?=?2.55?×?10?7), DRB1*10 (OR?=?0.45; p?=?0.002), DQB1*06:01 (OR?=?0.43; p?=?0.0001), and DQB1*05:02 (OR?=?0.28; p?=?2.1?×?10?4) in patients were suggested protective association. The combination of DRB1*03+AG (OR?=?5.21; p?=?1.4?×?10?6), DRB1*04+AG (OR?=?2.14; p?=?0.053), DRB1*04+GG (OR?=?5.21; p?=?0.036), DQB1*02:01+AG (OR?=?4.44; p?=?3.6?×?10?5), DQB1*02:02+AG (OR?=?20.9; p?=?9.5?×?10?4), and DQB1*02:02+GG (OR?=?4.06; p?=?0.036) revealed susceptible association. However, the combination of DRB1*10+AA (OR?=?0.35; p?=?0.003), DRB1*15+AA (OR?=?0.22; p?=?5.3?×?10?7), DQB1*05:01+AA (OR?=?0.45; p?=?0.007), DQB1*05:02+AA (OR?=?0.17; p?=?1.7?×?10?4), DQB1*06:01+AA (OR?=?0.40; p?=?0.002), and DQB1*06:02+AG (OR?=?0.34; p?=?0.001) showed decreased frequency in patients, suggesting protective association. In conclusion, CTLA4/HLA-DR/DQ genotypic combinations revealed strong susceptible/protective association toward T1DM in south India. A female preponderance in disease associations was also documented.  相似文献   

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Conjugative transfer of 20-kb chromosomal fragment carrying genes encoding tetracycline (tet r ) and lincomycin (lin r ) resistance in the soil strain Bacillus subtilis 19 is described. Transfer was preceded by this fragment insertion into the large conjugative p19cat plasmid producing a hybrid plasmid. Insertion frequency was 10?4?10?5. Then genes tet r and lin r were transferred to the recipient strains. The transfer of chromosomal genes inserted into the plasmid and plasmid gene cat occurred sequentially and resembled sexduction, which represents chromosomal gene transfer by F′ and R′ plasmids during conjugation in Escherichia coli and other gram negative bacteria.  相似文献   

20.
The association between alcoholic liver disease (ALD) and the inflammatory response remains controversial. The aim of this study was to explore this association between ALD and inflammation. We enrolled 214 male participants, who were divided into three age-matched groups: ALD (n?=?135), chronic alcohol ingestion without ALD (non-ALD; n?=?42), and control (n?=?37). The BMI was significantly higher in the ALD group than in the non-ALD and control groups (all P?=?0.000). Further, the constituent ratio of the liver inflammatory level was significantly higher in the ALD group than in the non-ALD and control groups (P?=?0.002 and P?=?0.000, respectively). In addition, the median serum ALT, AST, and GGT levels were significantly higher in the ALD group than in the control group (P?=?0.023, P?=?0.008, and P?=?0.000, respectively); these levels were also significantly higher in the ALD group than in the non-ALD group (P?=?0.013, P?=?0.010, and P?=?0.000, respectively). The median serum CRP level was significantly higher in the ALD group than in the non-ALD and control groups (P?=?0.006 and P?=?0.000, respectively). Further, the median serum TNF-α level was significantly lower in the ALD group than in the non-ALD and control groups (P?=?0.004 and P?=?0.000, respectively). The median serum sOX40L and HSP70 levels were significantly lower in the ALD group than in the control group (P?=?0.008 and P?=?0.018, respectively). In addition, the ALT, AST, and GGT levels were positively correlated with the CRP level (r?=?0.211, P?=?0.002; r?=?0.220, P?=?0.001 and r?=?0.295, P?=?0.000, respectively), and the GGT level was negatively correlated with the TNF-α (r?=??0.225, P?=?0.001), sOX40L (r?=??0.165, P?=?0.016), and HSP70 levels (r?=??0.178, P?=?0.009). Further, the Cr level was negatively correlated with the IL-10 level (r?=??0.166, P?=?0.015). Logistic regression analysis verified that the BMI (OR??=??1.637, 95%CI: 1.374–1.951, P??=??0.000) and GGT level were significantly higher (OR??=??1.039, 95%CI: 1.020–1.059, P??=??0.000) and that the TNF-α (OR??=??0.998, 95%CI: 0.996–1.000, P??=??0.030) and HSP70 levels were significantly lower (OR??=??1.017, 95%CI: 1.003–1.031, P??=??0.029) in the ALD group than in the non-ALD group. Further, the moderate-to-severe ALD patients had a significantly higher serum CRP level (Or?=???1.349, 95%CI: 1.066–1.702, P??=??0.013) and significantly lower HSP60 (OR??=??0.965, 95%CI: 0.938–0.993, P??=??0.014) and HSP70 levels (OR??=??0.978, 95%CI: 0.962–0.995, P??=??0.010) than the mild ALD patients. These results suggest that ALD patients may present with obesity, liver damage, and an imbalanced inflammatory immune response, mainly manifesting as decreased levels of immune inflammatory cytokines. In addition, they suggest that certain liver and kidney function parameters and ALD severity are either positively or negatively correlated with certain inflammatory cytokines. Hence, ALD patients may be at increased risks of obesity- and inflammation-related diseases. Accordingly, to control the inflammatory response, preventative measures for patients with this disease should include weight control and protection of liver and kidney function.  相似文献   

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