Stemphylium blight: Leaves dry at the edges with dark spots
Pathogen: Stemphylium vesicarium
Symptoms
Dark spots on the ends of dying stems can be seen. The leaves and leaf sheaths are small, light yellow to brown, and water-soaked. As the lesions expand they coalesce causing extensive blighting of the leaves.
Disease development
Extended periods of leaf wetness from dew formation, rainfall or overhead irrigation during bulb formation and development can result in severe leaf blighting. Bulb size can be greatly reduced due to loss of foliage. Infection is usually limited to leaves and does not extend down to the scales of the bulb.
Disease management
Good control of insects and other diseases is vital. This prevents weak tissue.There are a variety of fungicides that can prevent this disease from causing too much damage. In warm weather do not irrigate in crops with a slight Stemphylium infection.
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