Wednesday, October 30, 2013

Powdery Mildew - What to look for early season - Q&A


Above - Look out for Powdery Mildew flagshoots hidden inside your canopy.
This post shows the symptoms to look for in spring between budburst (EL-4) and 80% Capfall (EL-25) including flagshoots, upper leaf and lower leaf symptoms and infections on flowers. 

Powdery mildew often goes undetected (because of poor monitoring) until it is well established typically during flowering in mid-November.

Powdery mildew is best prevented by a combination of uV light, from an open canopy, and a good coverage of fungicide sprays.  

Low efficacy products like wettable sulphur and organic based oils will limit the development of powdery mildew if applied with good coverage. 


Above: Powdery mildew covering the back of a leaf in an organic, sulphur applied, chardonnay vineyard near McLaren Flat - October 2013.
Above: Upper leaf Powdery Mildew close up.
Above & Below: Severe powdery mildew on a Chardonnay inflorescence EL-17 Preflowering
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Above: Powdery in the low side of the leaf.

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