http://www.jnkvv.nic.in/IPM%20Project/disease-groundnut.html

http://vasat.icrisat.org/?q=node/83

Chemical Control of early leaf spot in groundnut

Early Leaf Spot 

   General

 

• Caused by Cercospora arachidicola
  

• Infection Starts Around 30 days after Sowing

 

Symptoms:

• Sub-circular dark brown spots are produced on the upper leaflet surface. The spots are of lighter shade of brown on the lower side of the leaflets. Yellow halo is seen around the brown spots.

• Oval to elongate spots are also seen on stems, petioles, and pegs. 
  

• Severe disease attack leads to shedding of leaflets (Fig.) resulting in premature ageing of the crop.
  

                       

Early Leaf Spot

Management: 

Good weed control is helpful as dense weed growth encourages disease development. Growing moderately resistant cultivars like ICGV 89104, ICGV 91114 (EM), ICGV 920920, ICGV 92093 (MM). Fungicidal control of leaf spots is effective. Foliar spray with Kavach or Bavistin @ 2 g/liter of water and 500 liters/ha. Copper, sulfur, and copper/sulfur dusts give good control of leaf spots and also some control of rust. But, these may be expensive. Bordeaux mixture spray gives good control of rust and leaf spots. But, difficult to prepare than modern fungicides. Maneb and Mancozeb sprays are effective in controlling leaf spots and give some control of rust.Benomyl spray results in excellent control of leaf spots. But, likely to stimulate production of tolerant strains of fungus.