Laboratory studies to assess the risk of development of resistance to zoxamide.

  title={Laboratory studies to assess the risk of development of resistance to zoxamide.},
  author={David H Young and Sebastian Śpiewak and Richard A. Slawecki},
  journal={Pest management science},
  volume={57 11},
Laboratory studies were conducted to evaluate the risk of developing field resistance to zoxamide, a new Oomycete fungicide which acts on microtubules. Zoxamide, metalaxyl and dimethomorph were compared with respect to the ease with which fungicide-resistant mutants could be isolated and their level of resistance. Attempts to generate mutants of Phytophthora capsici and P infestans with resistance to zoxamide by mycelial adaptation on fungicide-amended medium were unsuccessful. Similarly… 
Assessing the risk of resistance in Pseudoperonospora cubensis to the fungicide flumorph in vitro.
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Baseline sensitivity of natural population and resistance of mutants in Phytophthora capsici to zoxamide.
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The risk that the plant pathogen Phytophthora melonis develops resistance to carboxylic acid amide (CAA) fungicides was determined by measuring baseline sensitivities of field isolates, generating
Characterization of fludioxonil-resistant and pyrimethanil-resistant phenotypes of Penicillium expansum from apple.
A fitness cost was associated with fludioxonil highly resistant mutants of P. expansum and triple resistance to the three apple-postharvest fungicides could emerge and become a practical problem if resistance to pyrimethanil develops in P. expandsum populations.


Selection and characterization of Phytophthora parasitica mutants with ultraviolet-induced resistance to dimethomorph or metalaxyl
Mutants of Phytophthora parasitica Dast more or less resistant to dimethomorph or metalaxyl were obtained by treating mycelium with ultraviolet radiation and retained their resistance after sub-culturing on unamended agar medium.
Studies on the inheritance of resistance to metalaxyl in Phytophthora infestans
Single-oospore progeny from matings between field isolates of Phytophthora infestans either highly resistant or sensitive to metalaxyl were analysed for fungicide sensitivity in vitro, mating type
Mode of Action of Zoxamide (RH-7281), a New Oomycete Fungicide
It is concluded that the fungitoxic mechanism of RH-7281 involves inhibition of nuclear division as the result of covalent binding to β-tubulin and disruption of the microtubule cytoskeleton.
Development of laboratory tolerance to phosphorous acid, fosetyl-Al, and metalaxyl in Phytophthora capsici
A total of three phosphorous acid (H3PO3)-tolerant and five metalaxyl-tolerant mutants of Phytophthora capsici were recovered in vivo when populations of ˜ 107 zoospores were exposed to the chemical
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The 1984 report of A2 mating types of Phytophthora infestans (Mont.) de Bary in western Europe was the first indication of new and dramatic developments in populations of that Fungus, indicating changes were not restricted to western Europe but, rather, were worldwide.
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