The use of oil emulsions for improving the efficacy of alternaria eichhorniae mycoherbicide on water hyacinth [electronic resource].

Includes reference.

The fungus A[temaria eichhomiae ; salate #5 (Ae5) is being developed as a mycoherbicide agent for controlling water hyacinth (Eichhomia crassipes) in Egypt. Inoculum concentrations above 10% (mycelial wet weight) were equally effective in the management of water hyacinth. There was an inverse relationship between the fungal culture age (up to 9 week old) and inoculum infectivity; the younger mycelial inoculum was more virulent on the weed plants than older ones. Applications 0 fA e5 ina n aqueous carrier and/or in nine different invert/oil emulsions were evaluated for the biocontrol of water hyacinth without a post-treatment dew period under natural (outdoor) conditions. The invert/oil emulsions were developed to provide moisture and to retard evaporation from the fungal inoculum applied sa that the fungal propagules could germinate and infect the target weed under relatively dry conditions. All of the invert and/or oil emulsion formulations induced higher levels of disease on water hyacinth plants when compared to the aqueous suspension formulati~ under dew-free conditions. Reducing the oil content in the Ae5 emulsion formulati0Trom 30 to 5% had no significant effect on the formulation's infectivity against wate~ hyacinth. In the absence 0f dew, Ae5 formulated inc ottonseed 0 il emulsion c aus9d 100% contral of water hyacinth in the outdoor field plots 7 to 13 weeks after application. Thus, .the results confirm the utility and feasibility of oil emulsions as formulatingmatedals for bioherbicides under the lack of dew conditions.

Summary in Arabic.

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