, Volume 98, Issue 1, pp 17–20 | Cite as

Effect of hymexazol on growth and reproduction of low temperature Phytophthora species

  • H. H. Ho


The effect of hymexazol (3-hydroxy-5-methylisoxazole or HMI) on growth and reproduction of low temperature Phytophthora species with growth maxima under 30 °C, was studied on clarified V-8 juice agar medium at 50 μg/ml and 5 μg/ml. HMI severely inhibited growth of P. infestons, P. phaseoli, P. porri and P. syringae, retarded the growth of P. hibernalis and P. lateralis but enhanced the growth of P. fragariae and P. ilicis. Phytophthora cactorum and P. pseudotsugae with a maximal temperature of 30 °C were moderately inhibited.

HMI reduced or prevented sporangial production on agar medium by P. cactorum, P. hibernalis, P. ilicis, P. infestons, P. lateralis, P. phaseoli, P. porri and P. primulae, and suppressed chlamydospore formation in P. porri and to a lesser extent, P. lateralis. The production of sex organs was prevented by HMI in P. phaseoli, P. porri, and P. syringae, reduced in P. hibernalis and P. ilicis but unaffected in P. cactorum, P. primulae and P. psuedotsugae.


Agar Agar Medium Growth Maximum Phytophthora Phytophthora Species 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Martinus Nijhoff/Dr W. Junk Publishers 1987

Authors and Affiliations

  • H. H. Ho
    • 1
  1. 1.Department of BiologyState University of New YorkNew PaltzUSA

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