Sour Rot: Galactomyctes citri-aurantii (formally, Geotrichum candidum ).

Symptoms

• Very soft, watery decay.
• Distinct margin between decayed and healthy tissue.
• Sour odour detectable.

Occurrence

• Infection occurs in damaged fruit.
• Fungicide used to control blue & green moulds may not control Sour rot. (eg., USA accepted
• fungicides).
• Sour rot spores in soil can accumulate in recirculating water in dips and drenches.
• Spreads by contact after packing creating nests of infected fruit in boxes.

Management

• Careful handling reduces rind damage.
• Apply Guazatine fungicide within 24hrs of harvest.
• Strong emphasis of sanitisers when Guazatine fungicide not approved for use.

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