PESTS AND DISEASE MANAGEMENT

PESTS AND DISEASE MANAGEMENT

Insects

• Leaf eaters, pod borers, jassids, thrips can cause up to 70% losses in yields
• Flower beetles or blister beetles cause serious damage to flowers
• Without exception, all short duration pigeon pea varieties have to be sprayed twice between 50% and full flowering and twice between 50% and full pod to control insect pests using the listed pesticides in Table below. Consult the extension officer when to spray the pesticides.

Pests and chemical control options.

 

Elegant grasshopper at adult stage can only be controlled by hand picking.

Some of the pests

Aphids

Whitegrubs

Caterpillars

Elegant grasshoppers

Adults of blister beetle

Disease Management

Fusarium wilt

• It is a very common plant disease in Malawi
• Caused by Fusarium.
• It first attacks the roots and then migrates systemically to the rest of the plant
• It causes yellowing and loss of leaves
• The lower part of the stem becomes brown and then black.

Prevention

• Farmers are encouraged to use of resistant varieties like Sauma or Kachangu
• Uproot and burn wilted plants
• Use fields with no Fusarium wilt records
• Practice crop rotation where possible.

(Source-NCIPM)

Cecospora leafspot

• The disease is a problem in humid regions with prolonged wet conditions late in the season
• Can cause yield losses up to 85% when defoliation occurs before flowering and podding
• First appear as small circular to irregular necrotic spots or lesions usually on older leaves
• As the disease progresses the lesions coalesce causing leaf defoliation
• Lesions may appear on young branches and cause their tips to dry and die back.

Prevention

• Plant new crop away from perennial/ ratooned pigeon pea fields
• Use resistant varieties
• Practice crop rotation where possible
• Spray fungicides like Benomyl or Mancozeb before flowering.

Cercospora spots on leaves (Source-Handbook for Pigeon pea Diseases)

Cercospora spots on flowers (Source- NCIPM)

Powdery mildew

• It is moderately severe in some parts of Malawi
• Usually occurs due to the higher rainfall experienced in the main pigeon pea growing areas
• Early signs are small chlorotic spots on the upper side of the leaves
• White patches appear later on the lower surface that eventually cover all the leaves with white fungal like powdery dust especially young leaves, flowers and pods
• Can be controlled by: use of resistant varieties like Sauma or Kachangu and by planting early.

(Source-Handbook for P Pigeon pea Diseases)