Browsing by Author "Crump, D.H."

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    Occurrence of Nematophagous Fungi in Cyst Nematode Populations
    (1983-01) Crump, D.H.; Sayre, R.M.; Young, L.D.
    Crump, D. H., Sayre, R. M., and Young, L. D. 1983. Occurrence of nematophagous fungi in cyst nematode populations. Plant Disease 67:63-64. Females of the soybean cyst nematode and soil samples collected from several soybean-growing areas of Tennessee in July 1981 were examined for fungal pathogens with potential as biological control agents of the nematode. Females infected with Nematophthora gynophila were isolated at three sites from five samples of roots, and resting spores of the fungus were found at five sites in nine soil samples, including two sites where the nematode is declining. Females infected with Catenaria auxiliaris and resting spores of Verticilliwn chlamydosporium were also found. These fungi control populations of cereal cyst nematode in England.
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    A Quantitative Method For Extracting Resting Spores Of Two Nematode Parasitic Fungi, Nematophthora Gynophila And Verticillium Chlamydosporium, From Soil
    (1981) Crump, D.H.; Kerry, B.R.
    A method is described for quantitative extraction of Nematophthora gynophila and Verticillium chlamydosporium spores from soil. These two species of fungi can prevent populations of the cereal cyst-nematode, Heterodera avenae, increasing when susceptible cereal hosts "are grown. The soil sample is wet sieved and the spores separated by centrifugation on a high specific gravity solution of magnesium sulphate. The spore suspension is counted directly under a compound microscope (125 x ). About 80% of spores added to three soils of different texture were recovered. In a survey of 23 soils, spore numbers of both fungi were large where H. avenae failed to multiply on susceptible hosts, and small where the nematode was increasing or causing damage.