Powdery Mildew of Apples

Podosphaera leucotricha

Description:

A fungal disease that causes a white powdery covering on all above ground parts. When buds are infected the leaves may be brittle and curled, develop abnormally, drop prematurely or die. Infection of leaves may lead to wavy and upturned margins. Fruit usually shows fine, yellow to brown network pattern on the skin.
Infected winter shoots look thin and dried out and the buds look dried.

Species Affected:

Apples, Quince.
Jonathan and Gravenstein Apples are more susceptible than other varieties.

Biology:

Spores require high humidity to germinate but don't germinate in rain.
Infective when temperatures are between 11 and 280C.

Life Cycle:

Origin and History:

Distribution:

Significance:

Management and Control:

Removed infected winter shoots and destroy.
In spring remove infected shoots as they appear.
Apply fungicides.

Related and Similar Species:

References:

1291

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.HerbiGuide.com.au for more information.