TNAU Agritech Portal
Home | About Us | Success Stories | Farmers Association | Farmers' Innovation | Publications | Contact

Agricultural crops :: Oilseeds :: Sunflower

Downy Mildew: Plasmopara halstedii

Symptom
  • The disease spreads rapidly through seeds.
  • Symptoms of the disease are evident as seedling damping off, systemic infection, local foliar lesions and basal root or stem galls.
  • First symptoms are yellowing of the first pair of true leaves.
  • Sunflower plants carrying systemic infection are severely stunted and leaves are entirely chlorotic.
  • Affected plants bear abnormally thick, downward curled leaves showing prominent yellow and green mottling.
  • The stem becomes brittle. Small angular greenish yellow lesions may appear on leaves as a result of secondary infection.
  • Fungal growth is visible at lower surface.

Management

  • Seed treatment with Metalaxyl at the rate of 3 g per kg of seed has been found to give effective control.
  • Choice of planting sites and disposal of infected crop residues also give a fairly good control.
Sunflower Sunflower


Home | About Us | Success Stories | Farmers Association | Publications | Disclaimer | Contact Us

© 2016 TNAU. All Rights Reserved.