Matches in SemOpenAlex for { <https://semopenalex.org/work/W2024442881> ?p ?o ?g. }
Showing items 1 to 55 of
55
with 100 items per page.
- W2024442881 endingPage "1376" @default.
- W2024442881 startingPage "1376" @default.
- W2024442881 abstract "Apple scab caused by Venturia inaequalis (Cooke) Winter continues to be a significant concern for apple growers in Virginia and Maryland. Management of scab has relied on foliar fungicides including strobilurins (QoIs) such as trifloxystrobin (TFX). In recent years, populations of V. inaequalis with reduced sensitivity to the QoIs have been reported in other apple-growing regions of the United States (1,2). Although QoIs generally remain effective in the mid-Atlantic, concerns about the development of resistance in some Virginia and Maryland orchards prompted this study. Twenty-five isolates of V. inaequalis were obtained from scabby leaves from commercial and experimental orchards in Virginia in 2010 (n = 6) and 2011 (n = 14) and from a commercial orchard in Maryland (n = 5) in 2011. Orchards had previously been treated with QoI or sterol-inhibiting (SI) fungicides. Isolates of V. inaequalis were grown on potato dextrose agar (PDA) amended with 0, 0.1, or 1.0 μg ml –1 TFX with 100 μg ml –1 salicylhydroxamic acid (SHAM) and incubated at 19°C. Colony growth was measured weekly for 4 weeks. To account for the SI use at some orchards, isolates of V. inaequalis were also evaluated on PDA amended with 0, 0.5, or 1.0 μg ml –1 myclobutanil. Fungicide sensitivities were expressed as a percentage of the difference in colony growth using a discriminatory dose of 1.0 μg ml –1 TFX with SHAM or 1.0 μg ml –1 myclobutanil at 28 days. Isolates with <25% growth suppression (GS) were classified as fully resistant, whereas those with >70% GS were classified as sensitive. Isolates with 25 to 70% GS were classified as partially resistant. Effective concentration (EC 50 ) values (TFX concentration inhibiting colony growth by 50%) were also calculated for a subset of fully resistant and sensitive isolates. Of the 25 isolates tested, six were fully resistant to TFX (mean EC 50 value greater than 10.0 μg ml –1 ) and 10 were sensitive (mean EC 50 value of 0.04 μg ml –1 ± 0.05 μg ml –1 ). Nine isolates were classified as partially resistant. Some isolates showed more than a 200-fold increase in resistance to TFX, and one isolate grew almost as well on 10.0 μg ml –1 TFX as on the unamended control (GS of 3%). Current-season use of QoIs on isolate source trees was significantly associated with a lack of sensitivity Ç 2 (1) = 3.72 (P < 0.06). All six fully resistant isolates originated from QoI-treated commercial orchards, which had shown control failures. Seven of 10 isolates sensitive to QoIs originated from trees that had been treated with SIs during the isolation year. Resistance to myclobutanil was not significantly associated with resistance to TFX Ç 2 (1) = 1.220 (P < 0.5), and only one isolate was resistant (i.e. >25% GS) to both. Despite the long history of QoI use at the experimental orchards, no isolates fully resistant to TFX were identified there. To our knowledge, this is the first report of V. inaequalis isolates with resistance to TFX in Virginia and Maryland. Since SI resistance has been documented in Virginia (3) and resistance to both the SI and QoI chemical classes is a concern in the mid-Atlantic region (4), tank-mixing or alternating QoIs with broad-spectrum fungicides with different modes of action is recommended. References: (1). K. M. Cox et al. Phythopathology 99:S25, 2009. (2). K. E. Lesniak et al. Plant Dis. 95:927, 2011. (3) S. C. Marine et al. Plant Health Progress. doi:10.1094/PHP-2007-1113-01-RS, 2007. (4) E. E. Pfeufer and H. K. Ngugi. Phytopathology 102:272, 2012." @default.
- W2024442881 created "2016-06-24" @default.
- W2024442881 creator A5042608219 @default.
- W2024442881 creator A5045031144 @default.
- W2024442881 creator A5085488093 @default.
- W2024442881 date "2012-09-01" @default.
- W2024442881 modified "2023-10-16" @default.
- W2024442881 title "First Report of Reduced Sensitivity to a QoI Fungicide in Apple Scab (<i>Venturia inaequalis</i>) in Virginia and Maryland" @default.
- W2024442881 doi "https://doi.org/10.1094/pdis-03-12-0246-pdn" @default.
- W2024442881 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/30727164" @default.
- W2024442881 hasPublicationYear "2012" @default.
- W2024442881 type Work @default.
- W2024442881 sameAs 2024442881 @default.
- W2024442881 citedByCount "1" @default.
- W2024442881 countsByYear W20244428812016 @default.
- W2024442881 crossrefType "journal-article" @default.
- W2024442881 hasAuthorship W2024442881A5042608219 @default.
- W2024442881 hasAuthorship W2024442881A5045031144 @default.
- W2024442881 hasAuthorship W2024442881A5085488093 @default.
- W2024442881 hasConcept C144027150 @default.
- W2024442881 hasConcept C2778358966 @default.
- W2024442881 hasConcept C2780087045 @default.
- W2024442881 hasConcept C2780498275 @default.
- W2024442881 hasConcept C2780753983 @default.
- W2024442881 hasConcept C74600772 @default.
- W2024442881 hasConcept C86803240 @default.
- W2024442881 hasConceptScore W2024442881C144027150 @default.
- W2024442881 hasConceptScore W2024442881C2778358966 @default.
- W2024442881 hasConceptScore W2024442881C2780087045 @default.
- W2024442881 hasConceptScore W2024442881C2780498275 @default.
- W2024442881 hasConceptScore W2024442881C2780753983 @default.
- W2024442881 hasConceptScore W2024442881C74600772 @default.
- W2024442881 hasConceptScore W2024442881C86803240 @default.
- W2024442881 hasIssue "9" @default.
- W2024442881 hasLocation W20244428811 @default.
- W2024442881 hasLocation W20244428812 @default.
- W2024442881 hasOpenAccess W2024442881 @default.
- W2024442881 hasPrimaryLocation W20244428811 @default.
- W2024442881 hasRelatedWork W1497169669 @default.
- W2024442881 hasRelatedWork W1974961464 @default.
- W2024442881 hasRelatedWork W2013348738 @default.
- W2024442881 hasRelatedWork W2020804665 @default.
- W2024442881 hasRelatedWork W2024442881 @default.
- W2024442881 hasRelatedWork W2029730982 @default.
- W2024442881 hasRelatedWork W2151624280 @default.
- W2024442881 hasRelatedWork W2163201271 @default.
- W2024442881 hasRelatedWork W2248381345 @default.
- W2024442881 hasRelatedWork W2624929748 @default.
- W2024442881 hasVolume "96" @default.
- W2024442881 isParatext "false" @default.
- W2024442881 isRetracted "false" @default.
- W2024442881 magId "2024442881" @default.
- W2024442881 workType "article" @default.