Pathological Characterization and Molecular Analysis of Elsinoe Isolates Causing Scab Diseases of Citrus in Jeju Island in Korea

Two scab diseases are recognized currently on citrus: (i) citrus scab caused by Elsinoe fawcettii, which has several pathotypes; and (ii) sweet orange scab caused by E. australis. Pathogenicity and cultural characteristics among 36 isolates collected from Jeju Island were investigated. Of 30 isolates from satsuma mandarin, yuzu, and kinkoji, all were E. fawcettii; 27 were similar to the Florida broad host range pathotype and 3 were similar to the Florida narrow host range pathotype by inoculation of differential hosts. Six isolates from natsudaidai were nonpathogenic to satsuma mandarin, rough lemon, sour orange, grapefruit, cleopatra mandarin, and natsudaidai leaves, and were only pathogenic to natsudaidai fruit. Isolates from natsudaidai usually produced unique tomentose colonies on potato dextrose agar compared with isolates from other citrus species. The colonies were relatively fast growing, radially sulcate, larger, and more expansive than the gummy, mucoid colonies of other isolates. Isolates from Florida, Australia, Argentina, and Jeju Island (Korea) were genetically differentiated using random amplified polymorphic DNA markers. E. fawcettii from Korea, Florida, and Australia, E. australis from Argentina, and natsudaidai isolates clustered closely within groups, but were clearly distinguishable among groups.

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Pathotypes and Genetic Relationship of Worldwide Collections of Elsinoë spp. Causing Scab Diseases of Citrus

Phytopathology ◽

10.1094/phyto-99-6-0721 ◽

2009 ◽

Vol 99 (6) ◽

pp. 721-728 ◽

Cited By ~ 29

Author(s):

J. W. Hyun ◽

S. H. Yi ◽

S. J. MacKenzie ◽

L. W. Timmer ◽

K. S. Kim ◽

...

Keyword(s):

Host Range ◽

Sweet Orange ◽

Genetic Relationships ◽

Random Amplified Polymorphic Dna ◽

Elongation Factor ◽

Its Region ◽

The United States ◽

Broad Host Range ◽

Narrow Host Range ◽

Rapd Pcr

Two scab diseases are recognized currently on citrus: citrus scab, caused by Elsinoë fawcettii, and sweet orange scab, caused by E. australis. Because the two species cannot be reliably distinguished by morphological or cultural characteristics, host range and molecular methods must be used to identify isolates. Four pathotypes of E. fawcettii and two of E. australis have been described to date based on host range. The host specificity and genetic relationships among 76 isolates from Argentina, Australia, Brazil, Korea, New Zealand, and the United States were investigated. Based on pathogenicity tests on eight differential hosts, 61 isolates were identified as E. fawcettii and 15 as E. australis. Of 61 isolates of E. fawcettii, 24 isolates were identified as the Florida broad host range (FBHR) pathotype, 7 as the Florida narrow host range (FNHR) pathotype, 10 as the Tryon's pathotype, and 3 as the “Lemon” pathotype. Two new pathotypes, the “Jingeul” and the satsuma, rough lemon, grape-fruit, clementine (SRGC), are described, and four isolates did not fit into any of the known pathotypes of E. fawcettii. Of the 15 isolates of E. australis from Argentina and Brazil, 9 belonged to the sweet orange pathotype and 6 from Korea to the natsudaidai pathotype. E. fawcettii and E. australis were clearly distinguishable among groups by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) assays and the E. fawcettii group was divided into three subgroups, A-1, A-2, and A-3. The A-1 group was composed of the FBHR, FNHR, and SRGC pathotypes; some Lemon pathotypes; and the uncertain isolates. The A-2 subgroup included all of the Tryon's pathotype isolates and one of the three Lemon pathotype isolates and the A-3 group contained the Jingeul pathotype isolates. E. australis was differentiated into two groups: B-1, the natsudaidai pathotype isolates, and B-2, the sweet orange pathotype isolates. Isolates of E. fawcettii and E. australis were clearly distinguishable by sequence analysis of the internal transcribed spacer (ITS) region and the translation elongation factor 1 α (TEF) gene. There were also fixed nucleotide differences in the ITS and TEF genes that distinguished subgroups separated by RAPD-PCR within species. We confirmed two species of Elsinoë, two pathotypes of E. australis, and at least six pathotypes of E. fawcettii and described their distribution in the countries included in this study.

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Emergence and Dissemination of Enterobacteriaceae Isolates Producing CTX-M-1-Like Enzymes in Spain Are Associated with IncFII (CTX-M-15) and Broad-Host-Range (CTX-M-1, -3, and -32) Plasmids

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01070-06 ◽

2006 ◽

Vol 51 (2) ◽

pp. 796-799 ◽

Cited By ~ 82

Author(s):

Ângela Novais ◽

Rafael Cantón ◽

Raquel Moreira ◽

Luísa Peixe ◽

Fernando Baquero ◽

...

Keyword(s):

Host Range ◽

Broad Host Range ◽

Narrow Host Range

ABSTRACT The spread of CTX-M-1-like enzymes in Spain is associated with particular plasmids of broad-host-range IncN (bla CTX-M-32, bla CTX-M-1), IncL/M (bla CTX-M-1), and IncA/C2 (bla CTX-M-3) or narrow-host-range IncFII (bla CTX-M-15). The identical genetic surroundings of bla CTX-M-32 and bla CTX-M-1 and their locations on related 40-kb IncN plasmids indicate the in vivo evolution of this element.

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Effect of calcium sprays on the severity of internal browning in Brussels sprouts

Australian Journal of Experimental Agriculture ◽

10.1071/ea9710123 ◽

1971 ◽

Vol 11 (48) ◽

pp. 123 ◽

Cited By ~ 3

Author(s):

CR Millikan ◽

EN Bjarnason ◽

BC Hanger

Keyword(s):

Virus Infection ◽

Sweet Orange ◽

Poor Performance ◽

Sour Orange ◽

Brussels Sprouts ◽

Carrizo Citrange ◽

Rough Lemon ◽

The Poor ◽

Internal Browning ◽

Cleopatra Mandarin

Five scions and ten rootstocks were tested in an eight-year trial at Irymple, near Mildura, Victoria. The scions were two old-line Lisbons, a nucellar Eureka, and two old-line Eurekas. Cumulative yields averaged for the ten rootstocks and expressed as a percentage of the best scion were : Rix Lisbon 100, Doncaster Lisbon 99, Frost Nucellar Eureka 95, Rodwell Eureka 89, and Villa Franca Eureka 73. The rootstocks, with their percentage yields in parentheses, were : Rough lemon (100), Cavanagh sweet orange (90), Symons sweet orange (84), Marsh grapefruit (73, Cox sweet orange (74), Cleopatra mandarin (72). Seville sour orange (721, Sampson tangelo (69), Emperor mandarin (69), and Carrizo citrange (30). The poor performance of Carrizo citrange is discussed in terms of virus infection and incompatibility. The incidence and importance of scion overgrowth is also reported and discussed.

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Comparison of lemon varieties and rootstocks at Mildura, Victoria

Australian Journal of Experimental Agriculture ◽

10.1071/ea9710118 ◽

1971 ◽

Vol 11 (48) ◽

pp. 118

Author(s):

LM Stafford

Keyword(s):

Virus Infection ◽

Sweet Orange ◽

Poor Performance ◽

Sour Orange ◽

Carrizo Citrange ◽

Rough Lemon ◽

The Poor ◽

Cleopatra Mandarin

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Genome organization of thePseudomonas aeruginosanarrow host range plasmid R91–5 determined by deletion and cloning analysis

Genetics Research ◽

10.1017/s0016672300022114 ◽

1985 ◽

Vol 45 (2) ◽

pp. 195-198 ◽

Cited By ~ 1

Author(s):

R. J. Moore ◽

V. Krishnapillai

Keyword(s):

Genetic Analysis ◽

Host Range ◽

Restriction Enzyme ◽

Genome Organization ◽

Conjugative Plasmid ◽

Deletion Mutants ◽

Broad Host Range ◽

Dna Fragments ◽

Narrow Host Range ◽

Fertility Inhibition

SummaryBy physical and genetic analysis of deletion mutants of the narrow host range IncP-10P. aeruginosaconjugative plasmid R91–5 it has been shown that the phenotypes related to its transfer, namely the inhibition of the replication of the phage G101, entry exclusion and the fertility inhibition of the wide host range plasmid R18 map at kilobase coordinates 19·7–20·7, 18·5–19·7, 28·8–30·15 and/or 34·9–36·15, respectively. These locations have been confirmed by cloning restriction enzyme generated DNA fragments of R91–5 into a small broad host range, multicopy non-conjugative plasmid.

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Uptake and distribution of chloride, sodium and potassium ions in salt-treated citrus plants

Australian Journal of Agricultural Research ◽

10.1071/ar9830133 ◽

1983 ◽

Vol 34 (2) ◽

pp. 133 ◽

Cited By ~ 63

Author(s):

AM Grieve ◽

RR Walker

Keyword(s):

Sweet Orange ◽

Poncirus Trifoliata ◽

Potassium Ions ◽

Citrus Reticulata ◽

Rangpur Lime ◽

Rough Lemon ◽

Young Leaves ◽

Chloride Accumulation ◽

Sodium And Potassium ◽

Cleopatra Mandarin

Seedlings of a range of citrus rootstocks were grown under glasshouse conditions and supplied with dilute nutrient solution containing either 0 or 50 mM NaCl. The partitioning of accumulated chloride and sodium into and within the major organs was compared between plants of Rangpur lime (Citrus reticulata var. austera hybrid?), Trifoliata (Poncirus trifoliata) and sweet orange (C. sinensis). Rootstocks differed in their leaf and stem chloride and sodium concentrations, but there was little or no difference between the rootstocks in root chloride and sodium concentrations. The lowest leaf chloride and sodium concentrations were found in the top region of shoots of all rootstocks. The different patterns of accumulation of chloride and sodium found in the three rootstocks were consistent with the existence of apparently separate mechanisms which operate to limit the transport of these two ions from the roots into the young leaves of citrus plants. The chloride excluding ability of 10 rootstocks and two hybrids was also compared and assessed in relation to rootstock vigour. Sampling from the middle leaves on salt-treated plants enabled a distinction to be made between rootstocks in their chloride accumulation properties. Cleopatra mandarin (C. reticulata), Rangpur lime, Macrophylla (C. macrophylla) and Appleby smooth Seville (C. paradisi x C. sinensis) accumulated significantly less chloride than did Trifoliata and rough lemon (C. jambhiri). Differences in chloride accumulation properties between rootstocks were unrelated to rootstock vigour.

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Isolation of Polyvalent Bacteriophages by Sequential Multiple-Host Approaches

Applied and Environmental Microbiology ◽

10.1128/aem.02382-15 ◽

2015 ◽

Vol 82 (3) ◽

pp. 808-815 ◽

Cited By ~ 51

Author(s):

Pingfeng Yu ◽

Jacques Mathieu ◽

Mengyan Li ◽

Zhaoyi Dai ◽

Pedro J. J. Alvarez

Keyword(s):

Host Range ◽

Pseudomonas Syringae ◽

Burst Size ◽

Broad Host Range ◽

Ecological Significance ◽

Content Type ◽

Narrow Host Range ◽

Isolation Methods ◽

Culture Independent ◽

K 12

ABSTRACTMany studies on phage biology are based on isolation methods that may inadvertently select for narrow-host-range phages. Consequently, broad-host-range phages, whose ecological significance is largely unexplored, are consistently overlooked. To enhance research on such polyvalent phages, we developed two sequential multihost isolation methods and tested both culture-dependent and culture-independent phage libraries for broad infectivity. Lytic phages isolated from activated sludge were capable of interspecies or even interorder infectivity without a significant reduction in the efficiency of plating (0.45 to 1.15). Two polyvalent phages (PX1 of thePodoviridaefamily and PEf1 of theSiphoviridaefamily) were characterized in terms of adsorption rate (3.54 × 10−10to 8.53 × 10−10ml/min), latent time (40 to 55 min), and burst size (45 to 99 PFU/cell), using different hosts. These phages were enriched with a nonpathogenic host (Pseudomonas putidaF1 orEscherichia coliK-12) and subsequently used to infect model problematic bacteria. By using a multiplicity of infection of 10 in bacterial challenge tests, >60% lethality was observed forPseudomonas aeruginosarelative to uninfected controls. The corresponding lethality forPseudomonas syringaewas ∼50%. Overall, this work suggests that polyvalent phages may be readily isolated from the environment by using different sequential hosts, and this approach should facilitate the study of their ecological significance as well as enable novel applications.

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Construction of arsB and tetH Mutants of the Sulfur-Oxidizing Bacterium Acidithiobacillus caldus by Marker Exchange

Applied and Environmental Microbiology ◽

10.1128/aem.01235-08 ◽

2008 ◽

Vol 74 (18) ◽

pp. 5686-5694 ◽

Cited By ~ 22

Author(s):

Leonardo J. van Zyl ◽

Jolanda M. van Munster ◽

Douglas E. Rawlings

Keyword(s):

Host Range ◽

Kanamycin Resistance ◽

Broad Host Range ◽

Conjugation System ◽

Hybridization Probe ◽

Narrow Host Range ◽

Moderately Thermophilic ◽

Acidithiobacillus Caldus ◽

Sulfur Oxidizer ◽

Acidophilic Bacterium

ABSTRACT Acidithiobacillus caldus is a moderately thermophilic, acidophilic bacterium that has been reported to be the dominant sulfur oxidizer in stirred-tank processes used to treat gold-bearing arsenopyrite ores. It is also widely distributed in heap reactors used for the extraction of metals from ores. Not only are these bacteria commercially important, they have an interesting physiology, the study of which has been restricted by the nonavailability of defined mutants. A recently reported conjugation system based on the broad-host-range IncW plasmids pSa and R388 was used to transfer mobilizable narrow-host-range suicide plasmid vectors containing inactivated and partially deleted chromosomal genes from Escherichia coli to A. caldus. Through the dual use of a selectable kanamycin resistance gene and a hybridization probe made from a deleted portion of the target chromosomal gene, single- and double-recombinant mutants of A. caldus were isolated. The functionality of the gene inactivation system was shown by the construction of A. caldus arsB and tetH mutants, and the effects of these mutations on cell growth in the presence of arsenic and by means of tetrathionate oxidation were demonstrated.

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Silage Collected from Dairy Farms Harbors an Abundance of Listeriaphages with Considerable Host Range and Genome Size Diversity

Applied and Environmental Microbiology ◽

10.1128/aem.01859-12 ◽

2012 ◽

Vol 78 (24) ◽

pp. 8666-8675 ◽

Cited By ~ 35

Author(s):

Kitiya Vongkamjan ◽

Andrea Moreno Switt ◽

Henk C. den Bakker ◽

Esther D. Fortes ◽

Martin Wiedmann

Keyword(s):

Host Range ◽

Dairy Farm ◽

Dairy Farms ◽

Genomic Diversity ◽

Broad Host Range ◽

Content Type ◽

Narrow Host Range ◽

Food Borne ◽

Size Diversity ◽

Range Characterization

ABSTRACTSince the food-borne pathogenListeria monocytogenesis common in dairy farm environments, it is likely that phages infecting this bacterium (“listeriaphages”) are abundant on dairy farms. To better understand the ecology and diversity of listeriaphages on dairy farms and to develop a diverse phage collection for further studies, silage samples collected on two dairy farms were screened forL. monocytogenesand listeriaphages. While only 4.5% of silage samples tested positive forL. monocytogenes, 47.8% of samples were positive for listeriaphages, containing up to >1.5 × 104PFU/g. Host range characterization of the 114 phage isolates obtained, with a reference set of 13L. monocytogenesstrains representing the nine major serotypes and four lineages, revealed considerable host range diversity; phage isolates were classified into nine lysis groups. While one serotype 3c strain was not lysed by any phage isolates, serotype 4 strains were highly susceptible to phages and were lysed by 63.2 to 88.6% of phages tested. Overall, 12.3% of phage isolates showed a narrow host range (lysing 1 to 5 strains), while 28.9% of phages represented broad host range (lysing ≥11 strains). Genome sizes of the phage isolates were estimated to range from approximately 26 to 140 kb. The extensive host range and genomic diversity of phages observed here suggest an important role of phages in the ecology ofL. monocytogeneson dairy farms. In addition, the phage collection developed here has the potential to facilitate further development of phage-based biocontrol strategies (e.g., in silage) and other phage-based tools.

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Host specificity and vegetative compatibility of Dutch isolates of Fusarium oxysporum f.sp. asparagi

Canadian Journal of Botany ◽

10.1139/b97-041 ◽

1997 ◽

Vol 75 (3) ◽

pp. 383-393 ◽

Cited By ~ 21

Author(s):

Wim J. Blok ◽

Gerrit J. Bollen

Keyword(s):

Fusarium Oxysporum ◽

Host Range ◽

Plant Species ◽

Root Rot ◽

The United States ◽

Vegetative Compatibility ◽

Broad Host Range ◽

Vegetative Compatibility Groups ◽

Narrow Host Range

The host range of Fusarium oxysporum f.sp. asparagi (Foa) was studied in inoculation experiments with 21 plant species. Typical root rot symptoms were incited only in asparagus, in all experiments; lupin and pea were susceptible under in vitro conditions but showed only mild symptoms occasionally when tested in soil; none of the other species showed external disease symptoms. Root colonization by Foa was studied for 14 plant species. The pathogen was detected in externally disinfested roots of all species except leek and onion, with asparagus the most extensively colonized species. Asparagus was not susceptible to isolates of F. oxysporum f.sp. pisi, lupini, cepae, lilii, and gladioli and Fusarium sacchari var. elongatum. Naturally infested field soil was planted twice for 11 – 13 weeks with 11 plant species, including asparagus and several symptomless hosts, and subsequently with asparagus as a biotest plant. Of these crops, only asparagus greatly increased the severity of Foa root rot. It was concluded that Foa has a narrow host range as a pathogen but a broad host range as a parasite. The consequences of the latter for the epidemiology of Foa are discussed. Twenty-four Foa isolates were assigned to 18 different vegetative compatibility groups (VCGs); three additional F. oxysporum isolates, which were not pathogenic on asparagus, each belonged to a unique VCG. These findings indicate that the Dutch Foa population is very diverse genetically, as was found previously for the Foa population in the United States. Key words: asparagus, Fusarium oxysporum f.sp. asparagi, host range, lupin, pea, symptomless hosts, vegetative compatibility.

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