Downy mildew

Caused by: Plasmopara halstedi
Problem Category: Fungal Disease
Symptoms: Death of seedlings leading to reduced stand in field; if seedlings survive they may be chlorotic with thickened leaves; white cottony growth is present on leaf undersides; systemic infection causes stunted plant growth and reduced seed production
Comments: Disease emergence favors high humidity; fungus can survive in soil for up to 10 years
Management: Plant sunflower varieties that are resistant to downy mildew; treat seeds with an appropriate fungicide prior to planting; foliar fungicides are ineffective at controlling systemic infections and are not recommended
Control: Spray 6 litre Fermented butter milk to control the downy mildew