Search results for "Inoculation"
showing 10 items of 105 documents
Application of viability PCR to discriminate the infectivity of hepatitis A virus in food samples.
2015
Abstract Transmitted through the fecal–oral route, the hepatitis A virus (HAV) is acquired primarily through close personal contact and foodborne transmission. HAV detection in food is mainly carried out by quantitative RT-PCR (RT-qPCR). The discrimination of infectious and inactivated viruses remains a key obstacle when using RT-qPCR to quantify enteric viruses in food samples. Initially, viability dyes, propidium monoazide (PMA) and ethidium monoazide (EMA), were evaluated for the detection and quantification of infectious HAV in lettuce wash water. Results showed that PMA combined with 0.5% Triton X-100 (Triton) was the best pretreatment to assess HAV infectivity and completely eliminate…
An Optimized and Rapid DNA Extraction Method From Leaves of Grapevine Suitable for PCR-DGGE Based Analysis
2010
Molecular techniques and genetic studies require a fair amount of DNA of high quality in order to produce reliable and clear results (Li et al., 2007). In grapevine, the yield and quality of DNA can be significantly affected by secondary metabolites such as polyphenols, polysaccharides and tannins, that may be consistently abundant during the different stages of leaf development (Iandolino et al., 2004). The development of a simple, rapid and reliable method for the extraction of genomic DNA from grape leaves collected at several stages during development, as well as from healthy grape leaves and leaves infected by pathogenic microorganisms, was the main objective of this study. The protoco…
Occurrence of tomato pith necrosis caused by Pseudomonas marginalis in Italy.
2010
Dipartimento di Scienze e Tecnologie Fitosanitarie. Universita` degli Studi di Catania. Via Santa Sofia 100, 95123 Catania, ItalyIn 2006, a serious outbreak of tomato pith necrosis (TPN) with approxi-mately 90% disease incidence was observed in two greenhouses in Sicily.Adult fruiting plants showed chlorosis and slight wilting of shoot apices.Internalstem browning alongthe entire length oftheplant was observed.Pith tissues were soft but not rotted or hollowed. Only fluorescent colo-nies developed on King’s B medium (KB) after isolation from infected tis-sues. Ten pure isolates were all levan, oxidase, potato soft-rotting andarginine dihydrolase positive and were negative for tobacco hypersens…
Metabolomics Suggests That Soil Inoculation with Arbuscular Mycorrhizal Fungi Decreased Free Amino Acid Content in Roots of Durum Wheat Grown under N…
2015
Arbuscular mycorrhizal fungi (AMF) have a major impact on plant nutrition, defence against pathogens, a plant's reaction to stressful environments, soil fertility, and a plant's relationship with other microorganisms. Such effects imply a broad reprogramming of the plant's metabolic activity. However, little information is available regarding the role of AMF and their relation to other soil plant growth-promoting microorganisms in the plant metabolome, especially under realistic field conditions. In the present experiment, we evaluated the effects of inoculation with AMF, either alone or in combination with plant growth-promoting rhizobacteria (PGPR), on the metabolome and changes in metabo…
Survival of Erwinia amylovora in mature apple fruit calyces through the viable but nonculturable (VBNC) state
2009
Aims: Survival of Erwinia amylovora, causal agent of fire blight in pome fruits and other rosaceous plants, was monitored inside mature apples calyces under some storage conditions utilized in fruit. Methods and Results: Apple fruit calyces inoculated with two E. amylovora strains and their respective GFP-marked strains were maintained at 26° and 5°C, and the effect of copper treatment was assayed at 0·01 and 0·1 mmol l−1 CuSO4. In nontreated apples at 26°C, part of the population of E. amylovora survived in the ‘viable but nonculturable’ (VBNC) state, whereas at 5°C the majority of the population retained culturability. In copper-treated apples, the whole population adopted the VBNC stat…
Impairment of leaf hydraulics in young plants of Citrus aurantium (sour orange) infected by Phoma tracheiphila.
2007
Phoma trachephila (Petri) Kantschaveli et Gikachvili causes dieback of several Citrus species. The impact of this fungus on leaf hydraulics was studied in Citrus aurantium L. (sour orange) with the aim of identifying the primary mechanism of damage to leaves. Leaves inoculated with a conidial suspension were measured for conductance to water vapor (gL) and specific hydraulic conductance (Kleaf) every 3 days after inoculation. The earliest symptom of infection consisted of vein chlorosis. Functional vein density (FVD) was monitored and microscopic observations were made of major vein conduits. Impairment of vein hydraulics started 25 days after inoculation with a losses of Kleaf of 40% and g…
Biological control of Listeria monocytogenes in soil model systems by Enterococcus mundtii strains expressing mundticin KS production
2022
Abstract The agricultural practices applied in pre-harvest greatly influence the presence and the levels of microorganisms in fresh produce. Among these, Listeria monocytogenes represents one of the most lethal foodborne pathogens associated with vegetables. The main hypothesis of this work is that bacteriocin producer Enterococcus mundtii strains can be effective against L. monocytogenes in soil. To this purpose, bacteriocin production by E. mundtii WFE3, WFE20 and WFE31, three strains showing a strong bacteriocin activity in terms of inhibitory power and inhibition spectra, was evaluated in sterile extracts from agricultural soil and peat moss, in organic nutrient solution (ONS) and miner…
Isolation and Characterization of a New Less-Toxic Derivative of the Fusarium Mycotoxin Diacetoxyscirpenol after Thermal Treatment
2011
Trichothecenes are an important class of mycotoxins that act as potent protein synthesis inhibitors in eukaryotic organisms. The compound 4,15-diacetoxyscirpenol is highly toxic for plants and animals. Potatoes are especially prone to be contaminated with 4,15-diacetoxyscirpenol after infection with Fusarium sambucinum. In the current study, the reduction of 4,15-diacetoxyscirpenol during thermal treatment in aqueous solution was monitored. A new derivative was detected and named DAS-M1. After isolation, DAS-M1 was characterized with LC-HR-MS and LC-MS/MS and structurally elucidated with (1)H, (13)C, and 2D NMR. Potatoes were inoculated with F. sambucinum, and the infected potatoes were coo…
Colonization of tomato root by pathogenic and nonpathogenic Fusarium oxysporum strains inoculated together and separately into the soil.
2006
ABSTRACT In soil, fungal colonization of plant roots has been traditionally studied by indirect methods such as microbial isolation that do not enable direct observation of infection sites or of interactions between fungal pathogens and their antagonists. Confocal laser scanning microscopy was used to visualize the colonization of tomato roots in heat-treated soil and to observe the interactions between a nonpathogenic strain, Fo47, and a pathogenic strain, Fol8, inoculated onto tomato roots in soil. When inoculated separately, both fungi colonized the entire root surface, with the exception of the apical zone. When both strains were introduced together, they both colonized the root surface…
Effect of inoculation with selected Bradyrhizobium spp. on the survival and growth of Acacia mangium saplings after 20 months in the field
1999
This work was designed to test the long-term effect of the inoculation of #Acacia mangium# seedlings with 10 selected strains of #Bradyrhizobium spp.#. The percentage of survival of seedlings inoculated with any of the #Bradyrhizobium# strains was increased by 10% as compared to the control plants. However, out of the 10 #Bradyrhizobium# strains tested, only 3 strains, Aust l3c, Lu 4 and Tel 8, belonging to the phylogenelic group 1, significandy enhanced the growth of #A. mangium# after 20 months in the field. For the first time, inoculation with indigenous Malaysian strains #Bradyrhizobium# such as Tel 8 and Lu 4 at the seedling stage is reported to produce enhanced and sustained growth an…