COWPEA

Name of the diesease	Symptoms	Control Measures
POWDERY MILDEW	White fluffy, light greyish powdery growth on leaves, petioles, branches, stems, young shoots and pods. Under epidemic conditions, severe defoliation takes place and plants remain stunted. Cracking of stem and branches also take place in some cases.	Spray Sulfex (0.2%) or Bavistin (0.1%) or Benlate (0.1%) or Karathane (0.05%) at 10 days interval.
RUST	Numerous, small, circular flecks on the lower surface of leaves, petiole and stem. The pustules produce reddish brown powdery spots. Subsequently the colour of the pustules becomes black.	1. Spray Dithane M-45 (0.2%) or Difolatan (0.2%) at 15 days interval. Use resistant varieties.
SEPTORIA LEAF SPOT	Numerous circular to irregular, water soaked areas on both the leaf surfaces. These, later, turn light brown with dark brown margins. Under epidemic conditions, severe defoliation takes place.	1. Spray Difolatan (0.3%) or Benomyl (0.1%) or Dithane M-45 (0.2%) at 15 days interval. 2. Use resistant varieties.
ANTHRACNOSE	Individual lesions on stem are lenticular to sunken and tan to brown in colour. On pods, lesions develops as small brown spots which enlarge and then turn dark brown to black in the centre and light brown to pinkish on the border. Severely infected pods are deformed, shrivelled and small in size. Affected seeds show brownish lesions.	1. Spray Benlate (0.1%) or Difolatan ( 0.2%) or Dithane M-45 (0.2%) at 15 days interval. 2. Treat the seed with Thiram (0.3%) or Captan (0.3%).
CERCOSPORA LEAF SPOT	Circular to irregular, cherry red to reddish brown spots on leaves having diffused chlorotic halos, which soon become necrotic and rusty brown in colour.	Spray Dithane M-45 (0.2%) or Dithane Z-78 (0.2%) or Bavistin (0.1%) or Benlate (0.1%) at 15 days interval.
ASHY STEM BLIGHT	Same as under French bean.	Seed treatment with Bavistin (0.1%), Vitax (0.2%) or Ceresan wet or Thiram (0.2%).
COWPEA APHID- BORNE MOSAIC	Mosaic mottling of the leaves accompanied by slight crinkling and reduction in leaf size and typical dark green bands along the veins are symptoms commonly observed under field conditions.	1. This disease can be controlled by the use of virus free seeds. 2. Application of granular systemic insecticides like Furadon or disyston @ 1.5 kg a.i./ ha followed by 2-3foliare sprays of Dimecron (0.05%) or Dimethoate (0.05%) at 10 days interval reduces insect vector population spread. 3. Judicious combination of cultural practices like time of sowing, mixed cropping and insecticidal sprays would be helpful in disease management. 4. Planting of barrier crops like Jowar, Bajara or Maize 2-3 months in advance, around the field before sowing of cowpea seed would minimize disease incidence. 5. Mineral oil spray 1% or 2% can check the disease spread.
BACTERIAL BLIGHT Click on Image for larger photo.	Infected cotyledons become red and shrivelled. In case of severe infections, cotyledons, primary leaves and growing points are killed in the initial stage. Occassionally wilting of plants are also observed. Disease appears as light yellow, irregular to round spots on the lower surface to leaves, which in 2-3 days get enlarged into reddish brown, angular to circular, necrotic spots with chlorotic halo. Severely affected wither off. Dark green water soaked spots with varying number and shape are formed on pods, cracks are formed on stem & joint of the pod shells.	1. Lines TVU 200.347.401.456, 580, 726, 2460 and 4540 are found resistant. 2. Application of potassuim and molybednum as host nurtition reduces the disease. 3. Seed treatment with Plantomycin (0.01%) followed by 2 sprays of Plantomycin (0.01%) or Copper Oxychloride (0.3%) are found effective.