A fungal disease that initially shows as light grey spots with brown rims about 1-2 mm wide on the older leaves. They increase in size with time and may dry out and crack in the centre. Black spore bodies may appear in the middle of the spots. Occasionally they are on other parts of the plant.
Species Affected:
Beetroot, Silver Beet.
Chenopodiaceae family weeds.
Biology:
Spores are spread by wind, raindrop splash or insects to the younger leaves or adjacent plants.
It is favoured by warm temperatures of 24-300C and damp weather.
Life Cycle:
Origin and History:
Distribution:
Significance:
Makes infected leaves unsaleable.
Management and Control:
Control Chenopodium species weeds.
Rotate to resistant crops.
Don't plant Beet family crops on infected areas for 3-4 years.
Position crop as far away from previous Beet crops as possible.
Pick the crop regularly to prevent the disease becoming established.
Destroy infected leaves.
Fungicides can be used but are usually not necessary if the above are done.
Related and Similar Species:
References:
1205
Acknowledgments:
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