Ring Spot of Brassicas

Mycosphaerella brassicicola

Description:

Grey circular spots with black specks in concentric rings in the centre.

Species Affected:

Brassicas.

Biology:

Favoured by mild, wet conditions.

Infection occurs when leaves have been wet for 24 hours or more and symptoms develop about 2 weeks later.

Survives on infected crop stubble and in the soil.

Spread by wind or water splash from diseased crop or residues.

Life Cycle:

Origin and History:

Distribution:

Significance:

Management and Control:

Eliminate crop residues by deep burial soon after harvest.

Preventative fungicides should be applied at the first signs of the disease and repeated while wet conditions endure.

Related and Similar Species:

Septoria Tritici Blotch of Wheat (Mycosphaerella graminicola)

References:

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 for more information.