Acidifying Spray Suspensions of Oxytetracycline and Kasugamycin Enhances Their Effectiveness for Fire Blight Control in Apple and Pear.

The stability of the fire blight control material, oxytetracycline, in water is strongly affected by pH, increasing with increasing acidity. From 2017 to 2021, pear and apple orchard trials were conducted to evaluate if acidic amendments to oxytetracycline sprays improve fire blight control. Compared with the water-treated control, infection suppression after two bloom applications of an acidified commercial oxytetracycline formulation averaged 85.

Type III Secretion System Inhibitors Reduce Fire Blight Infection Under Field Conditions.

Fire blight, caused by , is an economically important disease in apples and pears worldwide. This pathogen relies on the type III secretion system (T3SS) to cause disease. Compounds that inhibit the function of the T3SS (T3SS inhibitors) have emerged as alternative strategies for bacterial plant disease management, as they block bacterial virulence without affecting growth, unlike traditional antibiotics.

Contribution of Native Plasmids of C9-1 to Epiphytic Fitness and Fire Blight Management on Apple and Pear Flowers and Fruits.

C9-1 (C9-1) is a biological control bacterium that is applied to apple and pear trees during bloom for suppression of fire blight, caused by . Strain C9-1 has three megaplasmids: pPag1, pPag2, and pPag3. Prior bioinformatic studies predicted these megaplasmids have a role in environmental fitness and/or biocontrol efficacy.

from the Fire Blight Biocontrol Product, Blossom Protect, Induces Host Resistance in Apple Flowers.

Fire blight, caused by , is a devastating disease of apple. Blossom Protect, a product that contains as the active ingredient, is one of the most effective biological controls of fire blight. It has been postulated that the mode of action of is to compete against and antagonize epiphytic growth of on flowers, but recent studies have found that flowers treated with Blossom Protect harbored similar to or only slightly reduced populations compared with nontreated flowers.

Identity and Pathogenicity of Fungi Associated with Root, Crown, and Vascular Symptoms Related to Winter Squash Yield Decline.

Winter squash ( cultivar Golden Delicious) produced in Oregon's Willamette Valley for edible seed production has experienced significant yield losses because of a soilborne disease. The symptoms associated with this disease problem include root rot, crown rot, and vascular discoloration in the stems, leading to a severe late season wilt and plant collapse. Through field surveys, , , like fungi, , and were identified to be associated with diseased tissues, and each produced symptoms of root rot, crown rot, or stem discoloration in preliminary pathogenicity trials.

Refinement of Nonantibiotic Spray Programs for Fire Blight Control in Organic Pome Fruit.

Fire blight-susceptible, certified organic pome fruit is produced on 9,000 ha in the Pacific Northwest region of the United States with acreage continuing to expand despite a 2014 prohibition on antibiotics as allowable materials for infection suppression. Nonantibiotic practices for fire blight pathogen suppression mirror conventional management, but the full-bloom-to-petal-fall period when antibiotics are typically sprayed for fire blight control continues to receive research scrutiny owing to drawbacks and weaknesses of alternative materials. As solitary treatments, effective nonantibiotic materials (e.

Induction of Systemic Acquired Resistance Aids Restoration of Tree Health in Field-Grown Pear and Apple Diseased with Fire Blight.

Induction of systemic acquired resistance as a therapeutic aid to restoration of tree health was evaluated in 3- to 14-year-old pear and apple trees diseased with fire blight. Acibenzolar-S-methyl (ASM) was applied to diseased trees in late spring near the time of removal of primary fire blight cankers, which had originated from floral infection. Suspensions of ASM (7.

Comparison of Methods of Acibenzolar-S-Methyl Application for Post-Infection Fire Blight Suppression in Pear and Apple.

Greenhouse-grown, 1-year-old potted 'Bosc' pear and apple rootstock cultivars 'M.9' and 'M.26' were inoculated with the fire blight pathogen, Erwinia amylovora, and subjected to trunk paint, root drench, or foliar spray treatments with acibenzolar-S-methyl (ASM, 4 to 30 mg a.

Evaluation of Dormant-Stage Inoculum Sanitation as a Component of a Fire Blight Management Program for Fresh-Market Bartlett Pear.

From 2010 to 2013, the efficacy of copper-based inoculum sanitation as a component of fire blight management programs was evaluated in commercial pear orchards located in northern California. Forty-one 4-ha sections of orchard were split into two equal-sized plots, with the orchardist applying horticultural oil alone to one plot and horticultural oil plus a fixed copper bactericide to the other plot. These treatments were timed to begin just prior to and finish at the "green tip" phenological stage, which occurs about 5 weeks before full bloom.

Quantitative Molecular Detection of Xanthomonas hortorum pv. carotae in Carrot Seed Before and After Hot-Water Treatment.

Molecular assays to detect and quantify DNA from viable cells of the seedborne pathogen Xanthomonas hortorum pv. carotae in carrot seed were developed and evaluated for use on nontreated and hot-water-treated seed lots. Both a TaqMan real-time polymerase chain reaction (PCR) assay and a loop-mediated isothermal amplification (LAMP) dilution endpoint assay detected and quantified DNA from viable pathogen cells after treatment of carrot seed washes with the live-dead discriminating dye propidium monoazide (PMA).

Evaluation of Strategies for Fire Blight Control in Organic Pome Fruit Without Antibiotics.

Apple and pear produced organically under the U.S. National Organic Program (NOP) standard can be treated with antibiotics for suppression of fire blight caused by Erwinia amylovora.

Evaluation of Loop-Mediated Isothermal Amplification for Rapid Detection of Erwinia amylovora on Pear and Apple Fruit Flowers.

Fire blight of pear and apple is frequently an inoculum-limited disease but weather-based forecasting models commonly assume that the pathogen is omnipresent. To improve fire blight risk assessment during flowering, we developed a rapid pathogen detection protocol that uses loop-mediated isothermal amplification (LAMP) to detect DNA of epiphytic Erwinia amylovora on samples of pear and apple flowers. LAMP detected a single flower colonized epiphytically by E.

Stress tolerance and environmental fitness of Pseudomonas fluorescens A506, which has a mutation in RpoS.

Establishment of suppressive populations of bacterial biological control agents on aerial plant surfaces is a critical phase in biologically based management of floral diseases. Periodically, biocontrol agents encounter inhospitable conditions for growth on plants; consequently, tolerance of environmental stresses may contribute to their fitness. In many gram-negative bacteria, including strains of Pseudomonas spp.

Pathogen refuge: a key to understanding biological control.

Pathogen refuge is the idea that some potentially infectious pathogen propagules are not susceptible to the influence of an antagonistic microbial agent. The existence of a refuge can be attributable to one or more factors, including temporal, spatial, structural, and probabilistic, or to the pathogen's evolved ability to acquire antagonist-free space prior to ingress into a plant host. Within a specific pathosystem, refuge size can be estimated in experiments by measuring the proportion of pathogen propagules that remain infective as a function of the amount of antagonist introduced to the system.

Routine femoral head fluoroscopy to reduce complications in coronary catheterization.

We tested whether routine preprocedure fluoroscopy of the femoral head would improve sheath placement or reduce the incidence of groin complications. Patients were randomized to receive either fluoroscopy or "blind" sheath placement using palpation alone. The location of the femoral sheath was established by femoral artery angiography.

Bioavailability of Iron to Pseudomonas fluorescens Strain A506 on Flowers of Pear and Apple.

ABSTRACT The addition of 0.1 mM FeCl(3) to a defined culture medium induces the bacterial epiphyte Pseudomonas fluorescens strain A506 (A506) to produce an antibiotic toxic to the fire blight pathogen, Erwinia amylovora. Consequently, because A506 is registered and applied as a commercial product to suppress E.

Evaluation of Likelihood of Co-Occurrence of Erwinia amylovora with Mature Fruit of Winter Pear.

ABSTRACT Phytosanitary concerns about fire blight prohibit export of U.S.-grown pears to some countries without this disease.

Biological Control Efficiency of Fusarium Wilt of Tomato by Nonpathogenic Fusarium oxysporum Fo-B2 in Different Environments.

ABSTRACT Efficiency of nonpathogenic Fusarium oxysporum Fo-B2 for the biological control of Fusarium wilt of tomato, caused by F. oxysporum f. sp.

Computed tomographic coronary angiography: experience at Baylor University Medical Center/Baylor Jack and Jane Hamilton Heart and Vascular Hospital.

Noninvasive cardiac computed tomographic imaging using multislice or electron beam technology has been shown to be highly specific and sensitive in diagnosing coronary heart disease. It is about a fifth of the cost of coronary angiography and is particularly well suited for evaluating patients with a low or low to moderate probability of having obstructive coronary atherosclerosis. In addition, it offers more information than calcium scoring: because of the intravenous contrast used, it temporarily increases the density of the lumen and allows differentiation of soft plaque from calcified plaque.

Effect of bivalirudin on length of stay in the recovery area after percutaneous coronary intervention compared with heparin alone, heparin + abciximab, or heparin + eptifibatide.

Three hundred nine patients were followed during their recovery area stay after percutaneous coronary intervention. Recovery area times for patients who received bivalirudin during percutaneous coronary intervention showed an average reduction in total recovery area length of stay of 36 minutes (p <0.0001) compared with patients who received heparin alone.

Validation of the i-STAT handheld activated clotting time for use with bivalirudin.

Bivalirudin is being used more frequently as an anticoagulant in the cardiac catheterization laboratory. Newer devices, used to measure activated clotting time (ACT), have not been thoroughly tested for use with bivalirudin. One such device, the i-STAT ACT, measures the generation of activated thrombin to determine the level of anticoagulation.