Sensitivity of Populations of Botrytis cinerea from Pear-Related Sources to Benzimidazole and Dicarboximide Fungicides

Botrytis cinerea is responsible for a major portion of postharvest decay in winter pears in the Pacific Northwest. The baseline sensitivity levels (mean EC50 values) of a wild-type B. cinerea population to thiabendazole and iprodione were 6.66 and 0.56 mg/liter, respectively. B. cinerea from commercial orchards not treated with a benzimidazole had significantly lower incidence of resistance (0.59%) to a discriminatory concentration of thiabendazole at 10 mg/liter than did isolates from orchards in which benomyl had been applied for experimental purposes (16.0%), unsprayed control trees in benomyl-sprayed orchards (5.34%), and isolates from packinghouses where thiabendazole was applied as a prestorage drench or packingline spray (3.23%). The mean EC50 value of isolates in the wild-type population was lower than those of resistant isolates from all other sources. High-level thiabendazole resistance (EC50 > 100 mg/liter) was found in 0.20% of isolates from unsprayed commercial orchards, 9.33% of isolates from benomyl-sprayed orchards, and 2.67% of isolates from unsprayed control trees in these benomyl-sprayed orchards. In isolates from packinghouses where a thiabendazole line spray was applied, 1.52% had high-level thiabendazole resistance. All isolates from all pear-related sources tested were sensitive to iprodione at 10 mg/liter. This study provides evidence supporting current recommendations of a single postharvest application of a benzimidazole to control decay caused by B. cinerea, and no application of benzimidazole fungicides in the orchard.

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Transcriptome Analysis Provides Insights into the Mechanism of Astaxanthin Enrichment in a Mutant of the Ridgetail White Prawn Exopalaemon carinicauda

Genes ◽

10.3390/genes12050618 ◽

2021 ◽

Vol 12 (5) ◽

pp. 618

Author(s):

Yue Jin ◽

Shihao Li ◽

Yang Yu ◽

Chengsong Zhang ◽

Xiaojun Zhang ◽

...

Keyword(s):

Transcriptome Analysis ◽

Underlying Mechanism ◽

Biological Processes ◽

Wild Type ◽

Expression Levels ◽

In The Wild ◽

Cuticle Proteins ◽

Apolipoprotein D ◽

High Level ◽

Lower Expression

A mutant of the ridgetail white prawn, which exhibited rare orange-red body color with a higher level of free astaxanthin (ASTX) concentration than that in the wild-type prawn, was obtained in our lab. In order to understand the underlying mechanism for the existence of a high level of free astaxanthin, transcriptome analysis was performed to identify the differentially expressed genes (DEGs) between the mutant and wild-type prawns. A total of 78,224 unigenes were obtained, and 1863 were identified as DEGs, in which 902 unigenes showed higher expression levels, while 961 unigenes presented lower expression levels in the mutant in comparison with the wild-type prawns. Based on Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes analysis, as well as further investigation of annotated DEGs, we found that the biological processes related to astaxanthin binding, transport, and metabolism presented significant differences between the mutant and the wild-type prawns. Some genes related to these processes, including crustacyanin, apolipoprotein D (ApoD), cathepsin, and cuticle proteins, were identified as DEGs between the two types of prawns. These data may provide important information for us to understand the molecular mechanism of the existence of a high level of free astaxanthin in the prawn.

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The PKS4 Gene of Fusarium graminearum Is Essential for Zearalenone Production

Applied and Environmental Microbiology ◽

10.1128/aem.00963-05 ◽

2006 ◽

Vol 72 (6) ◽

pp. 3924-3932 ◽

Cited By ~ 76

Author(s):

Erik Lysï¿½e ◽

Sonja S. Klemsdal ◽

Karen R. Bone ◽

Rasmus J. N. Frandsen ◽

Thomas Johansen ◽

...

Keyword(s):

Fusarium Graminearum ◽

High Performance ◽

Polyketide Synthase ◽

Wild Type ◽

Root Infection ◽

Enoyl Reductase ◽

Transformation Protocol ◽

Chromatography Analysis ◽

In The Wild ◽

High Level

ABSTRACT Zearalenones are produced by several Fusarium species and can cause reproductive problems in animals. Some aurofusarin mutants of Fusarium pseudograminearum produce elevated levels of zearalenone (ZON), one of the estrogenic mycotoxins comprising the zearalenones. An analysis of transcripts from polyketide synthase genes identified in the Fusarium graminearum database was carried out for these mutants. PKS4 was the only gene with an enoyl reductase domain that had a higher level of transcription in the aurofusarin mutants than in the wild type. An Agrobacterium tumefaciens-mediated transformation protocol was used to replace the central part of the PKS4 gene with a hygB resistance gene through double homologous recombination in an F. graminearum strain producing a high level of ZON. PCR and Southern analysis of transformants were used to identify isolates with single insertional replacements of PKS4. High-performance liquid chromatography analysis showed that the PKS4 replacement mutant did not produce ZON. Thus, PKS4 encodes an enzyme required for the production of ZON in F. graminearum. Barley root infection studies revealed no alteration in the pathogenicity of the PKS4 mutant compared to the pathogenicity of the wild type. The expression of PKS13, which is located in the same cluster as PKS4, decreased dramatically in the mutant, while transcription of PKS4 was unchanged. This differential expression may indicate that ZON or its derivatives do not regulate expression of PKS4 and that the PKS4-encoded protein or its product stimulates expression of PKS13. Furthermore, both the lack of aurofusarin and ZON influenced the expression of other polyketide synthases, demonstrating that one polyketide can influence the expression of others.

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Physical and physiological components of the graviresponses of wild-type and mutant Paramecium Tetraurelia

Journal of Experimental Biology ◽

10.1242/jeb.203.6.1059 ◽

2000 ◽

Vol 203 (6) ◽

pp. 1059-1070 ◽

Cited By ~ 2

Author(s):

U. Nagel ◽

H. Machemer

Keyword(s):

Swimming Speed ◽

Sedimentation Rates ◽

Paramecium Tetraurelia ◽

Wild Type ◽

Centre Of Gravity ◽

In The Wild ◽

Type Population ◽

G Value ◽

Mutant Cells

Wild-type and the morphological mutant kin 241 of Paramecium tetraurelia showed improved orientation away from the centre of gravity (negative gravitaxis) when accelerations were increased from 1 to 7 g. Gravitaxis was more pronounced in the mutant. A correlation between the efficiency of orientation and the applied g value suggests a physical basis for gravitaxis. Transiently enhanced rates of reversal of the swimming direction coincided with transiently enhanced gravitaxis because reversals occurred more often in downward swimmers than in upward swimmers. The results provide evidence of a physiological modulation of gravitaxis by means of the randomizing effect of depolarization-dependent swimming reversals. Gravity bimodally altered propulsion rates of wild-type P. tetraurelia so that sedimentation was partly antagonized in upward and downward swimmers (negative gravikinesis). In the mutant, only increases in propulsion were observed, although the orientation-dependent sensitivity of the gravikinetic response was the same as in the wild-type population. Observed swimming speed and sedimentation rates in the wild-type and mutant cells were linearly related to acceleration, allowing the determination of gravikinesis as a linear (and so far non-saturating) function of gravity.

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Alterations of Metabolic and Lipid Profiles in Polymyxin-ResistantPseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02656-17 ◽

2018 ◽

Vol 62 (6) ◽

Cited By ~ 15

Author(s):

Mei-Ling Han ◽

Yan Zhu ◽

Darren J. Creek ◽

Yu-Wei Lin ◽

Dovile Anderson ◽

...

Keyword(s):

Lipid A ◽

Therapeutic Option ◽

Polymyxin B ◽

Multidrug Resistant ◽

Wild Type ◽

Metabolomics Data ◽

Content Type ◽

In The Wild ◽

High Level ◽

Acyl Coenzyme A

ABSTRACTMultidrug-resistantPseudomonas aeruginosapresents a global medical challenge, and polymyxins are a key last-resort therapeutic option. Unfortunately, polymyxin resistance inP. aeruginosahas been increasingly reported. The present study was designed to define metabolic differences between paired polymyxin-susceptible and -resistantP. aeruginosastrains using untargeted metabolomics and lipidomics analyses. The metabolomes of wild-typeP. aeruginosastrain K ([PAK] polymyxin B MIC, 1 mg/liter) and its pairedpmrBmutant strains, PAKpmrB6and PAKpmrB12(polymyxin B MICs of 16 mg/liter and 64 mg/liter, respectively) were characterized using liquid chromatography-mass spectrometry, and metabolic differences were identified through multivariate and univariate statistics. PAKpmrB6and PAKpmrB12, which displayed lipid A modifications with 4-amino-4-deoxy-l-arabinose, showed significant perturbations in amino acid and carbohydrate metabolism, particularly the intermediate metabolites from 4-amino-4-deoxy-l-arabinose synthesis and the methionine salvage cycle pathways. The genomics result showed a premature termination (Y275stop) inspeE(encoding spermidine synthase) in PAKpmrB6, and metabolomics data revealed a decreased intracellular level of spermidine in PAKpmrB6compared to that in PAKpmrB12. Our results indicate that spermidine may play an important role in high-level polymyxin resistance inP. aeruginosa. Interestingly, bothpmrBmutants had decreased levels of phospholipids, fatty acids, and acyl-coenzyme A compared to those in the wild-type PAK. Moreover, the more resistant PAKpmrB12mutant exhibited much lower levels of phospholipids than the PAKpmrB6mutant, suggesting that the decreased phospholipid level was associated with polymyxin resistance. In summary, this study provides novel mechanistic information on polymyxin resistance inP. aeruginosaand highlights its impacts on bacterial metabolism.

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Optimum Timing of Preplant Applications of Glyphosate to Manage Rhizoctonia Root Rot in Barley

Plant Disease ◽

10.1094/pdis-05-10-0354 ◽

2011 ◽

Vol 95 (3) ◽

pp. 304-310 ◽

Cited By ~ 19

Author(s):

E. M. Babiker ◽

S. H. Hulbert ◽

K. L. Schroeder ◽

T. C. Paulitz

Keyword(s):

Disease Severity ◽

Pacific Northwest ◽

Root Rot ◽

Field Experiments ◽

Herbicide Application ◽

Rhizoctonia Root Rot ◽

The Pacific ◽

Seminal Roots ◽

Polymerase Chain ◽

High Level

Rhizoctonia root rot, caused by Rhizoctonia solani AG-8 and R. oryzae, is considered one of the main deterrents for farmers to adopt reduced-tillage systems in the Pacific Northwest. Because of the wide host range of Rhizoctonia spp., herbicide application before planting to control weeds and volunteer plants is the main management strategy for this disease. To determine the effect of timing of glyphosate applications on the severity of Rhizoctonia root rot of barley, field experiments were conducted in 2007, 2008, and 2009 in a field naturally infested with a high level of both R. solani and R. oryzae. Crop volunteer plants and weeds were allowed to grow over the winter and plots were sprayed with glyphosate at 42, 28, 14, 7, and 2 days prior to planting. As the herbicide application interval increased, there were significant increases in shoot length, length of the first true leaf, and number of healthy seminal roots and a decrease in disease severity. Yield and the number of seminal roots did not show a response to herbicide application interval in most years. The activity of R. solani, as measured by toothpick bioassay and real-time polymerase chain reaction, declined over time in all treatments after planting barley. The herbicide application interval required to meet 80 and 90% of the maximum response (asymptote) for all plant and disease measurements ranged from 11 to 27 days and 13 to 37 days, respectively. These times are the minimum herbicide application intervals required to reduce disease severity in the following crop.

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The Endochitinase of Clonostachysrosea Expression in Bacillus amyloliquefaciens Enhances the Botrytis cinerea Resistance of Tomato

International Journal of Molecular Sciences ◽

10.3390/ijms19082221 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2221 ◽

Cited By ~ 4

Author(s):

Yangyang Zheng ◽

Xudong Wang ◽

Siyuan Liu ◽

Kewei Zhang ◽

Zhibo Cai ◽

...

Keyword(s):

Superoxide Dismutase ◽

Botrytis Cinerea ◽

Molecular Mechanism ◽

Bacillus Amyloliquefaciens ◽

Chitinase Activity ◽

Wild Type ◽

Tomato Plants ◽

Significant Difference ◽

In The Wild ◽

Related Enzyme

To investigate whether the ech42 gene in Clonostachysrosea can improve the biocontrol efficacy of Bacillus amyloliquefaciens and its molecular mechanism. Compared to the wild type, the B. amyloliquefaciens transformed with the ech42 gene exhibited higher chitinase activity. The B. amyloliquefaciens-ech42 also showed significantly higher biocontrol efficiency compared to Botrytiscinerea when tomato plants were pre-treated with B. amyloliquefaciens-ech42. No significant difference in biocontrol efficiency was observed between the wild type and B.amyloliquefaciens-ech42 when tomato plants were first infected by Botrytiscinerea. In addition, the activity of the defense-related enzyme polyphenol oxidase, but not superoxide dismutase, was significantly higher in B. amyloliquefaciens-ech42 than in the wild type. The ech42 enhances the biocontrol efficiency of B.amyloliquefaciens by increasing the capacity of preventative/curative effects in plants, rather than by killing the pathogens.

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Quantification, Persistence, and Status of Dodine Resistance in New York and Michigan Orchard Populations of Venturia inaequalis

Plant Disease ◽

10.1094/pdis.1999.83.1.66 ◽

1999 ◽

Vol 83 (1) ◽

pp. 66-70 ◽

Cited By ~ 24

Author(s):

W. Köller ◽

W. F. Wilcox ◽

A. L. Jones

Keyword(s):

New York ◽

Venturia Inaequalis ◽

Indirect Evidence ◽

Historical Records ◽

Wild Type ◽

Baseline Sensitivity ◽

Relative Growth ◽

History Of ◽

Type Population ◽

Baseline Levels

Isolates of Venturia inaequalis were sampled from apple orchards during 1990 to 1996 and isolate sensitivities to dodine were determined by testing the relative growth (RG) of mycelial colonies at a discriminatory dose of 0.2 μg ml-1. Sensitivities were not significantly different for a wild-type population and several populations sampled from orchards never or rarely treated with dodine, and respective data were combined to provide a reference for baseline populations. The baseline sensitivity was compared with sensitivities determined for four orchards with evidence for practical dodine resistance. At these sites, increases of phenotype frequencies were most pronounced for isolates with RG values >90; they had increased from a baseline level of 0.9 to >30% and, therefore, were rated dodine-resistant. For two orchards with confirmed cases of previous dodine resistance, frequencies of resistant isolates had declined to 11 and 14% after dodine use was discontinued for 13 and 4 years, respectively. Sensitivities had not returned to baseline levels, and indirect evidence suggested that practical dodine resistance could recur rapidly in response to resumed dodine usage. Monitoring of commercial orchards in New York and Michigan revealed that dodine sensitivities were not uniform throughout regions where dodine resistance was widespread in the late 1970s. Sensitivities ranged from baseline to dodine-resistant and appeared to reflect the dodine use history at particular sites. Because the history of dodine use is not always known to growers, applications of dodine remain risky when accurate historical records are not available.

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NADPH Oxidase Is Crucial for the Cellular Redox Homeostasis in Fungal Pathogen Botrytis cinerea

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-05-19-0124-r ◽

2019 ◽

Vol 32 (11) ◽

pp. 1508-1516

Author(s):

Hua Li ◽

Shiping Tian ◽

Guozheng Qin

Keyword(s):

Nadph Oxidase ◽

Botrytis Cinerea ◽

Fungal Pathogen ◽

Molecular Mechanisms ◽

Redox Homeostasis ◽

Signal Transduction Pathway ◽

Regulatory Subunit ◽

Wild Type ◽

Mutant Proteins ◽

In The Wild

During interactions, both plants and pathogens produce reactive oxygen species (ROS). Plants generate ROS for defense induction, while pathogens synthesize ROS for growth, sporulation, and virulence. NADPH oxidase (NOX) complex in the plasma membrane represents a main protein complex for ROS production in pathogens. Although NOX plays a crucial role in pathogenicity of pathogens, the underlying molecular mechanisms of NOX, especially the proteins regulated by NOX, remain largely unknown. Here, we applied an iodoacetyl tandem mass tag-based redox proteomic assay to investigate the protein redox dynamics in deletion mutant of bcnoxR, which encodes a regulatory subunit of NOX in the fungal pathogen Botrytis cinerea. In total, 214 unique peptidyl cysteine (Cys) thiols from 168 proteins were identified and quantified in both the wild type and ∆bcnoxR mutant. The Cys thiols in the ∆bcnoxR mutant were generally more oxidized than those in the wild type, suggesting that BcNoxR is essential for maintaining the equilibrium of the redox state in B. cinerea. Site-specific thiol oxidation analysis indicated that 142 peptides containing the oxidized thiols changed abundance significantly in the ∆bcnoxR mutant. Proteins containing these differential peptides are classified into various functional categories. Functional analysis revealed that one of these proteins, 6-phosphate dehydrogenase, played roles in oxidative stress response and pathogenesis of B. cinerea. These results provide insight into the potential target proteins and the ROS signal transduction pathway regulated by NOX.

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A Chrysodeixis chalcites Single-Nucleocapsid Nucleopolyhedrovirus Population from the Canary Islands Is Genotypically Structured To Maximize Survival

Applied and Environmental Microbiology ◽

10.1128/aem.02409-13 ◽

2013 ◽

Vol 79 (24) ◽

pp. 7709-7718 ◽

Cited By ~ 13

Author(s):

Alexandra Bernal ◽

Oihane Simón ◽

Trevor Williams ◽

Delia Muñoz ◽

Primitivo Caballero

Keyword(s):

Canary Islands ◽

Transmission Efficiency ◽

Wild Type ◽

Content Type ◽

Biological Insecticide ◽

In The Wild ◽

Type Population ◽

Chrysodeixis Chalcites

ABSTRACTAChrysodeixis chalcitessingle-nucleocapsid nucleopolyhedrovirus wild-type isolate from the Canary Islands, Spain, named ChchSNPV-TF1 (ChchTF1-wt), appears to have great potential as the basis for a biological insecticide for control of the pest. An improved understanding of the genotypic structure of this wild-type strain population should facilitate the selection of genotypes for inclusion in a bioinsecticidal product. Eight genetically distinct genotypes were clonedin vitro: ChchTF1-A to ChchTF1-H. Quantitative real-time PCR (qPCR) analysis confirmed that ChchTF1-A accounted for 36% of the genotypes in the wild-type population. In bioassays, ChchTF1-wt occlusion bodies (OBs) were significantly more pathogenic than any of the component single-genotype OBs, indicating that genotype interactions were likely responsible for the pathogenicity phenotype of wild-type OBs. However, the wild-type population was slower killing and produced higher OB yields than any of the single genotypes alone. These results strongly suggested that the ChchTF1-wt population is structured to maximize its transmission efficiency. Experimental OB mixtures and cooccluded genotype mixtures containing the most abundant and the rarest genotypes, at frequencies similar to those at which they were isolated, revealed a mutualistic interaction that restored the pathogenicity of OBs. In OB and cooccluded mixtures containing only the most abundant genotypes, ChchTF1-ABC, OB pathogenicity was even greater than that of wild-type OBs. The ChchTF1-ABC cooccluded mixture killed larvae 33 h faster than the wild-type population and remained genotypically and biologically stable throughout five successive passagesin vivo. In conclusion, the ChchTF1-ABC mixture shows great potential as the active ingredient of a bioinsecticide to controlC. chalcitesin the Canary Islands.

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