DISEASE

NAME
Leaf Scorch
Stagonospora curtisii


Description
This is a casual fungal problem that infects the leaves.

Symptoms
The leaf tips are reddish brown soon after emerging, with small raised or lacerated spots that form longitudinal lines. These spots may also appear on the bulb scales and the flower, turning yellow-brown with a scorched appearance.

The infected areas become thin and papery while the lower leaf forms oval brown spots. As the spots enlarge the enclosed tissue turns white and dies. The leaf generally has a pale green washed out appearance and a heavy infection causes the leaf to bend and die.

Slimy base      Clivia miniata


Source and Dispersal
The fungus is found in the bud scales which are normally at ground level. The young leaves are infected as they grow past the scales. The spores are dispersed by wind or by the introduction of infested bulbs.

Hemerocallisspecies      White mycelium


Favoured Conditions
It prefers warm wet conditions that normally occur during spring as the leaves emerge.
     
Affected Plants
This fungus affects many bulbous plants including Daffodils, Jonquils, Belladonna lilies, Crinums, African lilies, Hippeastrums, Kaffir lilies.

Hemerocallisand Cliviaspecies may be infected Leaf Scorch causing the tips of the leaves to brown off and die.

          Clivia miniata

Non-chemical Control
Infected leaves should be cut off and disposed of by burning. Heavily infested bulbs should be dispensed with.

Chemical Control
Preventative spraying of copper oxychloride (fungicide) should be carried out as the leaves emerge.