Disease of Floral Buds of Kiwifruit in Spain Caused by Pseudomonas syringae

In 1999 and 2000, decay of floral buds of Actinidia deliciosa was observed in plantations in the Principality of Asturias, Spain. Bud decay led to a decrease (up to 40%) in the production of kiwifruit. Floral buds with symptoms of browning and necrosis were collected from different areas (Villaviciosa, Grado, and Pravia) and processed for microbiological analysis. A fluorescent bacterium was recovered on King's B medium and identified as Pseudomonas syringae by the LOPAT scheme and Hugh-Leifson reaction (2). Other biochemical features included esculin and gelatin hydrolysis and acid production from mannitol, erythritol, sorbitol, and m-inositol, which are features associated with P. syringae (2). Three isolates from different samples were selected to test pathogenicity using Koch's postulates. Overnight broth cultures of each isolate (109 CFU/ml) were used to infect A. deliciosa in the trials by the following procedures: (i) atomization on branches and buds; (ii) bud injection (1 ml in each bud); and (iii) bud cutting with a scalpel dipped in the suspension. Branches and buds inoculated with sterile water were used as controls. The inoculated parts were enclosed in plastic bags for 48 h. Assays were repeated at least twice. Disease symptoms appeared 2 days later, initially as dark brown spots that developed into an extensive bud rot in all inoculated cases, while no symptoms occurred in controls. P. syringae was successfully recovered from infected samples but not from control samples. The data support the pathogenicity of P. syringae on A. deliciosa. Although P. syringae was previously reported in Italy as the causal agent of disease on floral buds of A. deliciosa (1), to our knowledge, this is the first report of infection of kiwifruit by this pathogen in Spain. References: (1) G. M. Balestra and L. Varvaro. J. Phytopathol. 145:375, 1997. (2) MAPA, Manual de laboratorio, MAPA, Madrid, Spain, 1991.

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Changes in the Population Density of Pathogenic Microorganisms in Response to the Allelopathic Effect of Thypha Latifolia

Agricultural science and practice ◽

10.15407/agrisp1.01.031 ◽

2014 ◽

Vol 1 (1) ◽

pp. 31-36 ◽

Cited By ~ 3

Author(s):

O. Zhukorskiy ◽

O. Gulay ◽

V. Gulay ◽

N. Tkachuk

Keyword(s):

Cell Density ◽

Allelopathic Effect ◽

Pathogenic Microorganisms ◽

Sterile Water ◽

Erysipelothrix Rhusiopathiae ◽

Pathogenic Leptospira ◽

Favorable Conditions ◽

And Control ◽

The Impact ◽

Control Samples

Aim. To determine the response of the populations of Erysipelothrix rhusiopathiae and Leptospira interrogans pathogenic microorganisms to the impact of broadleaf cattail (Thypha latifolia) root diffusates. Methods. Aqueous solutions of T. latifolia root diffusates were sterilized by vacuum fi ltration through the fi lters with 0.2-micron pore diameter. The experimental samples contained cattail secretions, sterile water, and cultures of E. rhusiopathiae or L. interrogans. The same amount of sterile water, as in the experimental samples, was used for the purpose of control, and the same quantity of microbial cultures was added in it. After exposure, the density of cells in the experimental and control samples was determined. Results. Root diffusates of T. latifolia caused an increase in cell density in the populations of E. rhusiopathiae throughout the whole range of the studied dilutions (1:10–1:10000). In the populations of the 6 studied serological variants of L. interrogans spirochetes (pomona, grippotyphosa, copenhageni, kabura, tarassovi, canicola), the action of broadleaf cattail root diffusates caused the decrease in cell density. A stimulatory effect was marked in the experimental samples of the pollonica serological variant of leptospira. Conclusions. The populations of E. rhusiopathiae and L. interrogans pathogenic microorganisms respond to the allelopathic effect of Thypha latifolia by changing the cell density. The obtained results provide the background to assume that broadleaf cattail thickets create favorable conditions for the existence of E. rhusiopathiae pathogen bacteria. The reduced cell density of L. interrogans in the experimental samples compared to the control samples observed under the infl uence of T. latifolia root diffusates suggests that reservoirs with broadleaf cattail thickets are marked by the unfavorable conditions for the existence of pathogenic leptospira (except L. pollonica).

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PHYSICOCHEMICAL AND MICROBIAL ANALYSIS OF FECES FROM HORSES FED DIETS CONTAINING CITRUS PULP

Ciência Animal Brasileira ◽

10.1590/1089-6891v17i432332 ◽

2016 ◽

Vol 17 (4) ◽

pp. 527-533

Author(s):

Roberta Ariboni Brandi ◽

Adriana Moraes de Oliveira Tribucci ◽

Júlio César de Carvalho Balieiro ◽

Ricardo Luiz Moro de Souza ◽

Alfredo Manuel Franco Pereira ◽

...

Keyword(s):

Lactic Acid ◽

Latin Square ◽

Physicochemical Characteristics ◽

Microbiological Analysis ◽

Citrus Pulp ◽

Plastic Bags ◽

Microbiological Laboratory ◽

Acid Producing Bacteria ◽

Fecal Ph ◽

Lactobacillus Spp

Abstract This study aimed to evaluate the effect of diets containing increasing levels of citrus pulp on the physicochemical and microbiological characteristics of horses feces. Five mares, at an average age of 3.5 years old and body weight of 492 ± 44.5 kg were arranged in a 5 x 5 Latin Square. The experimental diet consisted of 60% coast-cross hay and 40 % of concentrate with increasing levels of citrus pulp (0, 7, 14, 21, and 28 %). To determine the fecal pH, samples were collected directly from the floor, immediately after defecation, in the first feces of the day at 07:00 a.m., and color and fecal consistency were evaluated. For microbiological analysis, an aliquot was reserved in plastic bags, frozen, and sent to the microbiological laboratory for further analysis. Lactic acid bacteria were counted for Lactobacillus spp. and Streptococcus spp. from fecal samples under anaerobic conditions. The diet produced differences (P<0.05) in feces consistency: 98% of the animals had normal and firm stools, while 2% were loose ruminant-type feces. We observed no difference (P<0.05) for color, verifying 100% of the animals of greenish feces, normal for equines. There was no effect (P>0.05) on pH and on the number of Lactobacillus spp. and Streptococcus spp. The inclusion of up to 28% citrus pulp concentrates for horses did not promote change in the physicochemical characteristics and on the population of lactic acid-producing bacteria in feces.

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First Report of Phoma exigua as a Pathogen of Salal (Gaultheria shallon) in British Columbia, Canada

Plant Disease ◽

10.1094/pd-89-0685b ◽

2005 ◽

Vol 89 (6) ◽

pp. 685-685 ◽

Cited By ~ 4

Author(s):

S. F. Shamoun ◽

S. Zhao

Keyword(s):

British Columbia ◽

The United States ◽

Gaultheria Shallon ◽

Centraalbureau Voor ◽

Potato Dextrose Broth ◽

Voucher Specimen ◽

Disease Symptoms ◽

Phoma Exigua ◽

First Report ◽

Plastic Bags

Salal (Gaultheria shallon Pursh.) is an ericaceous, evergreen, and rhizomatous shrub that competes for nutrients and moisture with young conifers in low elevation, coastal British Columbia (BC). A survey was conducted on southern Vancouver Island, BC during the summer of 1999 to find fungal pathogens of salal that might serve as biocontrol organisms (3). Phoma exigua Desmaz. (isolate PFC2705) near Parksville, BC proved to be pathogenic on salal. Identification of PFC2705 at the Centraalbureau voor Schimmelcultures was based on morphology and ITS sequences (GenBank Accession No. AY927784). Pathogenicity was determined with 24 salal seedlings (3-month-old) by inoculating with mycelial suspensions (20% v/v) or conidial suspensions (1 × 106 conidia per ml in 0.5% potato dextrose broth). Inoculated seedlings were placed in plastic bags and incubated in a greenhouse (16 to 23°C with natural light). Plastic bags were removed after 2 days. Initial disease symptoms were observed 2 days after inoculation. Brown, sunken lesions appeared on the surface of young leaves and stems and extended quickly. All seedlings were killed within 14 days. Twelve control plants showed no disease symptoms. With diseased salal leaves incubated at 23°C with 12-h fluorescent light/dark and 100% relative humidity, pycnidia appeared on leaf surfaces within 5 days. Conidia were hyaline, ellipsoid, one-celled, sometimes two- to three-celled, 2.5 to 3.8 × 5 to 12.5 μm, with a rounded base; the colony was gray or dark gray on potato dextrose agar after 5 to 7 days. Reisolation from the inoculated diseased leaves produced a mycelial colony that shared the same growth and morphological characteristics as the initial isolate. Phyllosticta gaultheriae Ellis & Everh., a widely reported foliar pathogen of salal, is distinct morphologically from P. exigua (1). To our knowledge, this is the first report of P. exigua as a pathogen of salal in Canada (2). A voucher specimen has been deposited at the Pacific Forestry Center Herbarium (DAVFP No. 28735). References: (1) J. Bissett and S. J. Darbyshire. No. 275 in: Fungi Canadenses, 1984. (2) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society. St. Paul. MN, 1989. (3) S. F. Shamoun et al. Can. J. Plant Pathol. 22:192, 2000.

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Preservation of Animal Cadavers with a Formaldehyde-free Solution for Gross Anatomy

Journal of Morphological Sciences ◽

10.1055/s-0038-1669434 ◽

2018 ◽

Vol 35 (02) ◽

pp. 136-141 ◽

Cited By ~ 2

Author(s):

Lynda Tamayo-Arango ◽

Anderson Garzón-Alzate

Keyword(s):

Benzalkonium Chloride ◽

Fungal Growth ◽

Gross Anatomy ◽

Microbiological Analysis ◽

Current Health ◽

Safety Regulations ◽

Plastic Bags ◽

Bovine Fetuses ◽

Color Preservation ◽

Arteries And Veins

AbstractMotivated by the current health safety regulations at Universidad de Antioquia, our laboratory changed the animal cadavers preserving solution based on formaldehyde, methanol, glycerin and phenol to a formula based on 85% ethanol, 10% glycerin, and 5% benzalkonium chloride. A total of 33 donated cadavers were preserved with this formula so far: 4 goats, 16 dogs, 3 cats and 10 bovine fetuses. Red and blue latex dyes were injected into the vascular systems. Small cadavers were first injected with latex, followed by muscular and intracavitary injection with the preservation fluid and immersion in 96% ethanol. Large cadavers were vascularly injected, wrapped in plastic bags and vascularly repleted with latex during the next 8 days. Samples were taken for microbiological analysis from 3 cadavers: 1 cadaver wrapped with plastic for 2 months, 1 cadaver immersed for 4 months, and 1 cadaver after 15 days of perfusion. The first way to preserve cadavers was more time-consuming, but it rendered cadavers with a more thorough distribution of latex on small arteries and veins. An enhanced flexibility of joints and tissues promoted an easier dissection process, even of the most distal regions, allowing the movement of tendons along their sheaths. Also, a better color preservation was observed in spite of a darkening after the tissues were exposed to the air. There was no gross evidence of decay from bacterial or fungal growth, and the cultures were negative. The most important advantage of this formula is its lower toxicity and cost.

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Identification and Characterization of a Well-Defined Series of Coronatine Biosynthetic Mutants of Pseudomonas syringae pv. tomato DC3000

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2004.17.2.162 ◽

2004 ◽

Vol 17 (2) ◽

pp. 162-174 ◽

Cited By ~ 137

Author(s):

David M. Brooks ◽

Gustavo Hernández-Guzmán ◽

Andrew P. Kloek ◽

Francisco Alarcón-Chaidez ◽

Aswathy Sreedharan ◽

...

Keyword(s):

Pseudomonas Syringae ◽

High Performance ◽

Tomato Dc3000 ◽

Disease Symptoms ◽

Coronafacic Acid ◽

Tn5 Mutants ◽

Cor Genes ◽

Identification And Characterization

To identify Pseudomonas syringae pv. tomato genes involved in pathogenesis, we carried out a screen for Tn5 mutants of P. syringae pv. tomato DC3000 with reduced virulence on Arabidopsis thaliana. Several mutants defining both known and novel virulence loci were identified. Six mutants contained insertions in biosynthetic genes for the phytotoxin coronatine (COR). The P. syringae pv. tomato DC3000 COR genes are chromosomally encoded and are arranged in two separate clusters, which encode enzymes responsible for the synthesis of coronafacic acid (CFA) or coronamic acid (CMA), the two defined intermediates in COR biosynthesis. High-performance liquid chromatography fractionation and exogenous feeding studies confirmed that Tn5 insertions in the cfa and cma genes disrupt CFA and CMA biosynthesis, respectively. All six COR biosynthetic mutants were significantly impaired in their ability to multiply to high levels and to elicit disease symptoms on A. thaliana plants. To assess the relative contributions of CFA, CMA, and COR in virulence, we constructed and characterized cfa6 cmaA double mutant strains. These exhibited virulence phenotypes on A. thalliana identical to those observed for the cmaA or cfa6 single mutants, suggesting that reduced virulence of these mutants on A. thaliana is caused by the absence of the intact COR toxin. This is the first study to use biochemically and genetically defined COR mutants to address the role of COR in pathogenesis.

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First Report of Erwinia persicinus Causing Wilting of Medicago sativa Sprouts in China

Plant Disease ◽

10.1094/pdis-10-11-0909 ◽

2012 ◽

Vol 96 (3) ◽

pp. 454-454 ◽

Cited By ~ 7

Author(s):

Z. F. Zhang ◽

Z. B. Nan

Keyword(s):

Medicago Sativa ◽

16S Rdna ◽

Acid Production ◽

Northwest China ◽

Gansu Province ◽

Microbiological Analysis ◽

Forage Crops ◽

First Report ◽

Production Of Hydrogen ◽

Hydrolysis Of

Medicago sativa L. is one of the most important perennial forage crops and has been cultivated for more than 2,000 years in China. A previously unreported sprout wilt disease of M. sativa, affecting as much as 25% of the seedlings, was observed in northwest China (Gansu Province) in March 2011. First symptoms on the sprouts were dehydration and yellowing. Within 24 to 48 h, the sprouts stopped growing, wilted, turned brown, and bacteria began oozing from the material. Three symptomatic sprout samples collected from a grower with the wilt problem were processed for microbiological analysis. Bacteria isolated from symptomatic samples produced a pink, diffusible pigment in King's medium B and nutrient agar supplemented with glucose, sucrose, and maltose. The three isolates were negative for gram stain reaction, oxidase, production of hydrogen sulfide and indole, growth in KCN broth, arginine dihydrolase activity, hydrolysis of casein, hydrolysis of gelatin, and acid production from L-arabinose, dulcitol, glycerol, lyxose, and starch. In contrast, they were positive for catalase, nitrate reduction, Voges-Proskauer, hydrolysis of aesculin, acid production from D-ribose, maltose and sucrose, assimilation of adonitol, L-lactate, mannitol, Myo-inositol, erythritol, sorbitol, and sucrose, and growth in 5% NaCl at 36°C. The 16S rDNA of three isolates (Cp1, Cp2, and Cp3) was amplified using the 7F (5′-CAGAGTTTGATCCTGGCT-3′) and 1540R (5′-AGGAGGTGATCCAGCCGCA-3′) primers. The sequences for the 1,428-bp amplicon from the isolates were identical (GenBank Accession No. JN900058) and had 99% sequence identity with 16S rDNA of Erwinia persicinus strains (including the type strain LMG 11254 [GenBank Accession No. Z96086.1], GS 04 [GenBank Accession No. DQ365580.1], LPPA 373 [GenBank Accession No. AJ937837.1], LPPA 408 [GenBank Accession No. AM294946.1], LMG 2691 [GenBank Accession No. AJ001190.1], and HK 204 [GenBank Accession No. NR_026049.1]). The three isolates were also evaluated in pathogenicity tests. Bacterial suspensions (108 CFU/ml) were spray inoculated on 7-day-old M. sativa sprouts of cv. Algonquin. The inoculated sprouts were placed onto 2% water agar in petri dishes (five sprouts per 9-cm dish) with four dishes for each bacterial isolate and control. The dishes were sealed with Parafilm for 2 days and held in an incubator at 25°C with a 12-h photoperiod. Assays were repeated twice. Symptoms that developed within 7 days were similar to those originally observed, whereas symptoms did not occur on control sprouts sprayed with sterile distilled water. Bacteria sharing the characteristics of the inoculated isolates were recovered from symptomatic sprouts, hence fulfilling Koch's postulates. E. persicinus has been isolated previously from Phaseolus vulgaris (1), Pisum sativum (2), tomato, banana, and cucumber (3). To our knowledge, this is the first report of E. persicinus from M. sativa. References: (1) A. J. González et al. Plant Dis. 89:109, 2005. (2) A. J. González et al. Plant Dis. 91:460, 2007. (3) M. V. Hao et al. Int. J. Syst. Bacteriol. 40:379, 1990.

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New Zealand flower thrips and their impact on nectarine fruit diseases

New Zealand Plant Protection ◽

10.30843/nzpp.2003.56.6035 ◽

2003 ◽

Vol 56 ◽

pp. 157-163

Author(s):

G.F. McLaren ◽

J.A. Fraser ◽

P.A. Alspach

Keyword(s):

New Zealand ◽

Pseudomonas Syringae ◽

Brown Rot ◽

Bacterial Disease ◽

Disease Symptoms ◽

Bacterial Diseases ◽

Flower Thrips ◽

Beginning Of Flowering ◽

Thrips Obscuratus ◽

The Impact

Insecticides fungicides and a bactericide were applied in spring 2001 and 2002 to nectarine trees to determine the impact of thrips (mainly New Zealand flower thrips Thrips obscuratus) on summerfruit pathogens Thrips numbers were assessed over 7 weeks from the beginning of flowering The insecticide programme increased the proportion of fruit meeting export standards for thrips damage but did not influence the level of either brown rot caused by Monilinia fructicola or the bacterial diseases bacterial blast (Pseudomonas syringae) and bacterial spot (Xanthomonas arboricola pv pruni) The fungicide programme reduced the level of brown rot Cumulative thrips counts were positively correlated with levels of brown rot infection on the fruit at harvest time in 2001/02 (P002) and 2002/03 (P009) and bacterial disease symptoms in 2001/ 02 (P003) It was concluded that New Zealand flower thrips could increase levels of disease in nectarines but the value of treating with insecticides was not clear

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First Report of Stem Blight Caused by Botrytis cinerea on Jasminum officinalis in Italy

Plant Disease ◽

10.1094/pdis-92-12-1708b ◽

2008 ◽

Vol 92 (12) ◽

pp. 1708-1708

Author(s):

D. Aiello ◽

G. Parlavecchio ◽

A. Vitale ◽

G. Polizzi

Keyword(s):

Botrytis Cinerea ◽

Far East ◽

Weather Conditions ◽

Economic Loss ◽

Transparent Plastic ◽

Disease Symptoms ◽

First Report ◽

Stem Blight ◽

Plastic Bags ◽

Stem Lesions

Common jasmine (Jasminum officinalis L.) is an evergreen shrub that is native to the Middle and Far East. It is widely grown in Europe as an ornamental plant and in southeastern France for fragrance for the perfume industry. In March of 2008, a previously undescribed disease was observed on potted (6-month- to 3-year-old) common jasmine plants growing in open fields in a nursery of eastern Sicily, Italy. More than 20% of the plants showed disease symptoms. Diseased plants had small to large, brown or black lesions on stem. The lesions expanded rapidly, girdled the stem and caused blight of entire branches, and occasionally killed the plant. Abundant conidia and mycelia were detected on the surface of dead and dying stems under cool and humid conditions, which resulted in a moldy gray appearance. Botrytis cinerea Pers.:Fr. (1) was consistently isolated from affected tissues disinfected for 1 min in 1% NaOCl, rinsed in sterile water, and plated on potato dextrose agar (PDA). Colonies were at first white then became gray after 6 to 7 days when spores differentiated. White sclerotia developed after 8 to 9 days and turned black with age. Size of the conidia produced on 1-month-old culture ranged from 5.0 to 9.5 × 6.5 to 12.5 μm on the basis of 50 spore measurements. Sclerotia were spherical or irregular and ranged from 1.0 to 2.5 × 0.9 to 2.9 mm (average 1.7 × 1.8 mm). Stems of eight 6-month-old common jasmine plants were lightly wounded with a sterile razor and inoculated with 3-mm-diameter plugs of PDA from 10-day-old mycelial cultures, eight similar plants were inoculated with mycelium without wounding, and an equal number of noninoculated plants inoculated with only PDA plugs served as control. After inoculation, plants were enclosed in transparent plastic bags at 20 ± 2°C for 5 days. Stem lesions identical to the ones observed in the nursery were detected on all wounded and on two nonwounded fungus-inoculated plants within 5 to 7 days. Control plants remained healthy. B. cinerea was reisolated from typical lesions. The unusually cool and humid weather conditions recorded in Sicily are supposed to be highly conducive of disease outbreak. Although B. cinerea does not usually kill the plants, under these environmental conditions this disease can cause significant economic loss to ornamental nurseries. To our knowledge, this is the first report of B. cinerea causing stem blight on J. officinalis. Reference: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CAB, Kew, Surrey, England, 1971.

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Identification of Resistance to Peppery Leaf Spot among Brassica juncea and Brassica rapa Plant Introductions

HortScience ◽

10.21273/hortsci.42.5.1140 ◽

2007 ◽

Vol 42 (5) ◽

pp. 1140-1143 ◽

Cited By ~ 6

Author(s):

W. Patrick Wechter ◽

Mark W. Farnham ◽

J. Powell Smith ◽

Anthony P. Keinath

Keyword(s):

Brassica Juncea ◽

Pseudomonas Syringae ◽

Brassica Rapa ◽

Leaf Spot ◽

Plant Introduction ◽

Leafy Vegetables ◽

Leaf Spot Disease ◽

Disease Symptoms ◽

Plant Introductions ◽

Leafy Greens

Brassica leafy greens (Brassica juncea L. and Brassica rapa L.) represent one of the most economically important vegetable crop groups in the southeastern United States. In the last 10 years, numerous occurrences of a leaf-spot disease on these leafy vegetables have been reported in several states. This disease, known as peppery leaf spot, is now causing serious crop losses and has been attributed to the bacterial phytopathogen Pseudomonas syringae pv. maculicola (Psm). To date, it appears that all cultivars of the Brassica leafy greens are susceptible, and available pesticides for control of this disease appear unable to reduce the disease to acceptable levels. Thus, we undertook a search for potential resistance to this disease among accessions of B. juncea and B. rapa included in the U.S. Plant Introduction (PI) collection. In greenhouse trials, we screened commercial cultivars and 672 U.S. PIs (226 B. juncea and 446 B. rapa) for resistance to Psm with artificial inoculation. Although severity of disease symptoms was significantly different among inoculated accessions, no acceptable levels of resistance were found in any of the more than 400 B. rapa accessions tested. Only two B. juncea accessions (PI 195553 and G 30988) of 226 tested had acceptable levels of resistance that might prove economically useful.

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Microbiological analysis of water and thickeners used for people with dysphagia

British Journal of Community Nursing ◽

10.12968/bjcn.2020.25.sup8.s16 ◽

2020 ◽

Vol 25 (Sup8) ◽

pp. S16-S24 ◽

Cited By ~ 1

Author(s):

Elizabeth Boaden ◽

Lois Thomas ◽

Susan Caroline ◽

Higham Watkins

Keyword(s):

Water Quality ◽

Room Temperature ◽

Tap Water ◽

Intervention Strategy ◽

Water Sources ◽

Microbiological Analysis ◽

Sterile Water ◽

Thickening Agent ◽

Growth Of Bacteria

Thickened fluids are a recognised intervention strategy in use for people with dysphagia. However, their bacterial profile has not previously been examined. Aims: To identify bacteria and changes in bacterial profiles in a range of water sources and thickener preparations over a 5-day period. Methods: Nine experiments were performed using a range of preparations (sterile, drinking, non-drinking tap water) and a thickening agent (sterile sachet and a used tin). Findings: No bacteria were grown on serial subcultures of sterile water, both with and without thickener. Drinking, tap and thickened water left at room temperature for 24 hours may become contaminated with environmental organisms. Conclusions: The growth of bacteria in preparations of thickening agent appears to be dependent upon water quality, while the proliferation of bacteria is dependent upon the length of time the preparation is allowed to stand at room temperature.

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