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Helical filaments produced by a Mycoplasma-like organism associated with corn stunt disease

R E Davis, J F Worley, R F Whitcomb

    Science (New York, N.Y.)
    |May 5, 1972
    PubMed

    Insights

    Helical filaments, identified as mycoplasma-like organisms, were observed in corn stunt-infected plants. These structures are associated with disease development and aid in diagnosing infections.

    Area of Science:

    • Plant Pathology
    • Microbiology
    • Cell Biology

    Background:

    • Corn stunt disease poses a significant threat to maize production.
    • The causative agent of corn stunt has been hypothesized to be a mycoplasma-like organism (MLO).
    • Previous studies have lacked definitive visualization of the MLO's morphology and cellular structures.

    Purpose of the Study:

    • To visualize and characterize the morphology of the presumed corn stunt agent.
    • To investigate the cellular structures of the MLO using advanced microscopy techniques.
    • To correlate the presence of the MLO with disease development and diagnosis.

    Main Methods:

    • Phase contrast microscopy was used to observe MLOs in plant tissue extracts.
    • Electron microscopy, including freeze-etching and thin-section techniques, was employed for detailed ultrastructural analysis.
    • Infection status and disease symptoms were assessed in corn plants.

    Main Results:

    • Helical filaments, bounded by a unit membrane, were identified as the MLO.
    • These filaments were observed within phloem cells of infected plants.
    • The presence of these filaments correlated with disease development and was useful for diagnosing infection, even in asymptomatic plants.

    Conclusions:

    • The observed helical filaments are consistent with the morphology of the mycoplasma-like organism causing corn stunt.
    • The findings support the hypothesis that MLOs are the etiological agents of corn stunt disease.
    • The study provides a basis for improved diagnosis of corn stunt disease through MLO identification.

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