Onion – White Rot

Key Points:

  1. Onion white rot is caused by a soil-borne fungus, Sclerotium cepivorum
  2. White rot affects all Allium plants including
    onions, leeks, garlic, chives,
    shallots and salad onions

  3. Leaves of infected plants show yellowing, dieback
    and wilting

  4. As the disease
    progresses, the white fungal mass fills with many
    tiny black bodies – like poppy seeds – called sclerotia.
    The sclerotia are able to
    survive for at least 15 years in the soil even
    without a suitable host plant

Control measures:

    • Good machinery and equipment hygiene
    • Fungicides
    • Reduced Irrigation
    • Wider plant spacing

Matters of Facts #05 Onion White Rot, Sclerotinia, October 2003
No.05 download pdf 105kb


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