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Kerik D Cox - One of the best experts on this subject based on the ideXlab platform.
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effects of consecutive Streptomycin and kasugamycin applications on epiphytic bacteria in the apple phyllosphere
Plant Disease, 2017Co-Authors: K A Tancos, Kerik D CoxAbstract:Antibiotic applications are essential for fire blight management in the eastern United States. Recently, Streptomycin-resistant Erwinia amylovora strains were found in New York. There are growing concerns that Streptomycin resistance may develop from postbloom Streptomycin applications in local orchards. Our goal was to investigate the impacts of increasing Streptomycin and kasugamycin applications on bacterial epiphyte community composition and antibiotic resistance in the phyllosphere of 'Idared' apple plantings in 2014 and 2015. Rinsate samples from leaves treated with 0, 3, 5, and 10 applications of Streptomycin and kasugamycin were collected to isolate, enumerate, and identify epiphytic bacterial species. The majority of isolated epiphytic bacteria were identified as Pantoea agglomerans and fluorescent Pseudomonas spp., whereas E. amylovora was rarely found. Overall, postbloom Streptomycin use did not result in an increased recovery of Streptomycin-resistant E. amylovora. However, other Streptomycin-resistant epiphytes (P. agglomerans and Pseudomonas spp.) did increase with increasing Streptomycin applications. Increasing kasugamycin applications reduced the overall number and percentage of Streptomycin-resistant epiphytes in the phyllosphere, which has important implications regarding the use of kasugamycin in orchards where Streptomycin resistance is a concern.
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prevalence of Streptomycin resistant erwinia amylovora in new york apple orchards
Plant Disease, 2016Co-Authors: K A Tancos, Deborah I Breth, Herb S Aldwinckle, Sara M Villani, S Kuehne, E E Borejszawysocka, J Carol, Kerik D CoxAbstract:Resistance to Streptomycin in Erwinia amylovora was first observed in the United States in the 1970s but was not found in New York until 2002, when Streptomycin-resistant (SmR) E. amylovora was isolated from orchards in Wayne County. From 2011 to 2014, in total, 591 fire blight samples representing shoot blight, blossom blight, and rootstock blight were collected from 80 apple orchards in New York. From these samples, 1,280 isolates of E. amylovora were obtained and assessed for Streptomycin resistance. In all, 34 SmR E. amylovora isolates were obtained from 19 individual commercial orchards. The majority of the resistant isolates were collected from orchards in Wayne County, and the remaining were from other counties in western New York. Of the 34 resistant isolates, 32 contained the Streptomycin resistance gene pair strA/strB in the transposon Tn5393 on the nonconjugative plasmid pEA29. This determinant of Streptomycin resistance has only been found in SmR E. amylovora isolates from Michigan and the SmR E. amylovora isolates discovered in Wayne County, NY in 2002. Currently, our data indicate that SmR E. amylovora is restricted to counties in western New York and is concentrated in the county with the original outbreak. Because the resistance is primarily present on the nonconjugative plasmid, it is possible that SmR has been present in Wayne County since the introduction in 2002, and has spread within and out of Wayne County to additional commercial growers over the past decade. However, research is still needed to provide in-depth understanding of the origin and spread of the newly discovered SmR E. amylovora to reduce the spread of Streptomycin resistance into other apple-growing regions, and address the sustainability of Streptomycin use for fire blight management in New York.
Patricia S Mcmanus - One of the best experts on this subject based on the ideXlab platform.
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Streptomycin application has no detectable effect on bacterial community structure in apple orchard soil
Applied and Environmental Microbiology, 2013Co-Authors: Ashley Shade, Amy K Klimowicz, Russell N Spear, Matthew Linske, Justin J Donato, Clifford S Hogan, Patricia S Mcmanus, Jo HandelsmanAbstract:Streptomycin is commonly used to control fire blight disease on apple trees. Although the practice has incited controversy, little is known about its nontarget effects in the environment. We investigated the impact of aerial application of Streptomycin on nontarget bacterial communities in soil beneath Streptomycin-treated and untreated trees in a commercial apple orchard. Soil samples were collected in two consecutive years at 4 or 10 days before spraying Streptomycin and 8 or 9 days after the final spray. Three sources of microbial DNA were profiled using tag-pyrosequencing of 16S rRNA genes: uncultured bacteria from the soil (culture independent) and bacteria cultured on unamended or Streptomycin-amended (15 μg/ml) media. Multivariate tests for differences in community structure, Shannon diversity, and Pielou's evenness test results showed no evidence of community response to Streptomycin. The results indicate that use of Streptomycin for disease management has minimal, if any, immediate effect on apple orchard soil bacterial communities. This study contributes to the profile of an agroecosystem in which antibiotic use for disease prevention appears to have minimal consequences for nontarget bacteria.
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effect of Streptomycin treatment on bacterial community structure in the apple phyllosphere
PLOS ONE, 2012Co-Authors: Erika Yashiro, Patricia S McmanusAbstract:We studied the effect of many years of Streptomycin use in apple orchards on the proportion of phyllosphere bacteria resistant to Streptomycin and bacterial community structure. Leaf samples were collected during early July through early September from four orchards that had been sprayed with Streptomycin during spring of most years for at least 10 years and four orchards that had not been sprayed. The percentage of cultured phyllosphere bacteria resistant to Streptomycin at non-sprayed orchards (mean of 65%) was greater than at sprayed orchards (mean of 50%) (P = 0.0271). For each orchard, a 16S rRNA gene clone library was constructed from leaf samples. Proteobacteria dominated the bacterial communities at all orchards, accounting for 71 of 104 OTUs (determined at 97% sequence similarity) and 93% of all sequences. The genera Massilia, Methylobacterium, Pantoea, Pseudomonas, and Sphingomonas were shared across all sites. Shannon and Simpson’s diversity indices and Pielou’s evenness index were similar among orchards regardless of Streptomycin use. Analysis of Similarity (ANOSIM) indicated that long-term Streptomycin treatment did not account for the observed variability in community structure among orchards (R = −0.104, P = 0.655). Other variables, including time of summer, temperature and time at sampling, and relative distance of the orchards from each other, also had no significant effect on bacterial community structure. We conclude that factors other than Streptomycin exposure drive both the proportion of Streptomycin-resistant bacteria and phylogenetic makeup of bacterial communities in the apple phyllosphere in middle to late summer.
K A Tancos - One of the best experts on this subject based on the ideXlab platform.
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effects of consecutive Streptomycin and kasugamycin applications on epiphytic bacteria in the apple phyllosphere
Plant Disease, 2017Co-Authors: K A Tancos, Kerik D CoxAbstract:Antibiotic applications are essential for fire blight management in the eastern United States. Recently, Streptomycin-resistant Erwinia amylovora strains were found in New York. There are growing concerns that Streptomycin resistance may develop from postbloom Streptomycin applications in local orchards. Our goal was to investigate the impacts of increasing Streptomycin and kasugamycin applications on bacterial epiphyte community composition and antibiotic resistance in the phyllosphere of 'Idared' apple plantings in 2014 and 2015. Rinsate samples from leaves treated with 0, 3, 5, and 10 applications of Streptomycin and kasugamycin were collected to isolate, enumerate, and identify epiphytic bacterial species. The majority of isolated epiphytic bacteria were identified as Pantoea agglomerans and fluorescent Pseudomonas spp., whereas E. amylovora was rarely found. Overall, postbloom Streptomycin use did not result in an increased recovery of Streptomycin-resistant E. amylovora. However, other Streptomycin-resistant epiphytes (P. agglomerans and Pseudomonas spp.) did increase with increasing Streptomycin applications. Increasing kasugamycin applications reduced the overall number and percentage of Streptomycin-resistant epiphytes in the phyllosphere, which has important implications regarding the use of kasugamycin in orchards where Streptomycin resistance is a concern.
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prevalence of Streptomycin resistant erwinia amylovora in new york apple orchards
Plant Disease, 2016Co-Authors: K A Tancos, Deborah I Breth, Herb S Aldwinckle, Sara M Villani, S Kuehne, E E Borejszawysocka, J Carol, Kerik D CoxAbstract:Resistance to Streptomycin in Erwinia amylovora was first observed in the United States in the 1970s but was not found in New York until 2002, when Streptomycin-resistant (SmR) E. amylovora was isolated from orchards in Wayne County. From 2011 to 2014, in total, 591 fire blight samples representing shoot blight, blossom blight, and rootstock blight were collected from 80 apple orchards in New York. From these samples, 1,280 isolates of E. amylovora were obtained and assessed for Streptomycin resistance. In all, 34 SmR E. amylovora isolates were obtained from 19 individual commercial orchards. The majority of the resistant isolates were collected from orchards in Wayne County, and the remaining were from other counties in western New York. Of the 34 resistant isolates, 32 contained the Streptomycin resistance gene pair strA/strB in the transposon Tn5393 on the nonconjugative plasmid pEA29. This determinant of Streptomycin resistance has only been found in SmR E. amylovora isolates from Michigan and the SmR E. amylovora isolates discovered in Wayne County, NY in 2002. Currently, our data indicate that SmR E. amylovora is restricted to counties in western New York and is concentrated in the county with the original outbreak. Because the resistance is primarily present on the nonconjugative plasmid, it is possible that SmR has been present in Wayne County since the introduction in 2002, and has spread within and out of Wayne County to additional commercial growers over the past decade. However, research is still needed to provide in-depth understanding of the origin and spread of the newly discovered SmR E. amylovora to reduce the spread of Streptomycin resistance into other apple-growing regions, and address the sustainability of Streptomycin use for fire blight management in New York.
Herb S Aldwinckle - One of the best experts on this subject based on the ideXlab platform.
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prevalence of Streptomycin resistant erwinia amylovora in new york apple orchards
Plant Disease, 2016Co-Authors: K A Tancos, Deborah I Breth, Herb S Aldwinckle, Sara M Villani, S Kuehne, E E Borejszawysocka, J Carol, Kerik D CoxAbstract:Resistance to Streptomycin in Erwinia amylovora was first observed in the United States in the 1970s but was not found in New York until 2002, when Streptomycin-resistant (SmR) E. amylovora was isolated from orchards in Wayne County. From 2011 to 2014, in total, 591 fire blight samples representing shoot blight, blossom blight, and rootstock blight were collected from 80 apple orchards in New York. From these samples, 1,280 isolates of E. amylovora were obtained and assessed for Streptomycin resistance. In all, 34 SmR E. amylovora isolates were obtained from 19 individual commercial orchards. The majority of the resistant isolates were collected from orchards in Wayne County, and the remaining were from other counties in western New York. Of the 34 resistant isolates, 32 contained the Streptomycin resistance gene pair strA/strB in the transposon Tn5393 on the nonconjugative plasmid pEA29. This determinant of Streptomycin resistance has only been found in SmR E. amylovora isolates from Michigan and the SmR E. amylovora isolates discovered in Wayne County, NY in 2002. Currently, our data indicate that SmR E. amylovora is restricted to counties in western New York and is concentrated in the county with the original outbreak. Because the resistance is primarily present on the nonconjugative plasmid, it is possible that SmR has been present in Wayne County since the introduction in 2002, and has spread within and out of Wayne County to additional commercial growers over the past decade. However, research is still needed to provide in-depth understanding of the origin and spread of the newly discovered SmR E. amylovora to reduce the spread of Streptomycin resistance into other apple-growing regions, and address the sustainability of Streptomycin use for fire blight management in New York.
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isolation of Streptomycin resistant isolates of erwinia amylovora in new york
Plant Disease, 2008Co-Authors: Nicole L Russo, Thomas J Burr, Deborah I Breth, Herb S AldwinckleAbstract:ABSTRACT Streptomycin is currently the only antibiotic registered for the control of fire blight, a devastating disease of apple (Malus), pear (Pyrus), and other rosaceous plants caused by the bacterium Erwinia amylovora. Resistance of E. amylovora to Streptomycin was first identified in California pear orchards in 1971 and is currently endemic in many parts of the United States. The Northeast remains the only major U.S. apple-growing region without Streptomycin-resistant isolates of E. amylovora. In 2002, during a routine survey for Streptomycin resistance, isolates from two neighboring orchards in Wayne County, NY were found to be highly resistant to Streptomycin at a concentration of 100 μg/ml. This constitutes the first authenticated report of Streptomycin resistance in New York State. Infected trees were shipped at the same time from a single nursery in Michigan. Resistance was caused by the acquisition of the strA-strB gene pair, inserted into the ubiquitous nontransmissible E. amylovora plasmid pEA...
James M Musser - One of the best experts on this subject based on the ideXlab platform.
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characterization of rpsl and rrs mutations in Streptomycin resistant mycobacterium tuberculosis isolates from diverse geographic localities
Antimicrobial Agents and Chemotherapy, 1996Co-Authors: Srinand Sreevatsan, Xi Pan, Kathryn E Stockbauer, Diana L Williams, Barry N Kreiswirth, James M MusserAbstract:Two genes (rpsL and rrs) with mutations associated with Streptomycin resistance in Mycobacterium tuberculosis were characterized in 78 Streptomycin-resistant and 61 Streptomycin-susceptible isolates recovered from patients living in the United States, South America, Europe, Africa, and Asia. Fifty-four percent of the 78 resistant organisms had missense mutations in codon 43 of rpsL resulting in a K-43-->R substitution. Mutations in codon 88 of rpsL were also identified in four Asian isolates.