Pests and Diseases

Mango Seed Weevil

It is known by the scientific name sternochetus mangiferae.

Diagnosis / Symptoms

  • The adult is dark brownish with pale patches, 1cm long, a curved snout and black eyes
  • The larva is small , white and legless with brown head and can be seen inside the husk
  • Partly eaten embryo inside of the husk
  • The adults emerge from the ripening fruit by tunneling through the fruit
  • Mango seeds damaged/destroyed by the weevil larvae have no external signs of damage to the fruit.
  • Attacked fruits fall off prematurely but most times not.

Control

  • Plant less susceptible varieties like Ngowe or Boribo
  • Collect all fallen fruits and destroy them either by burning or burying.
  • Spray weekly with Malathion, Dimethoate, Sumicidin, Marshal 25EC from flowering until the fruits are 1 inch in diameter
  • Paint the trunk with white paint mixed with dusburn or Malathion during the flowering stage to prevent the adult weevil from climbing tree from their hibernation site

Mango White Scales

It is known by the scientific name aulacaspis cinnamoni. The pests are found on green fruits and leaves

Diagnosis/ Symptoms

  • Appear as reddish brown legless and wingless insects 1mm long
  • They make flat or circular white scales/clusters with 3 ridges on the body
  • Adults come out of the scales as dark yellow with black eyes
  • Due to sucking by the pest infested spots on fruit skin turn yellow and become depressed making fruits less attractive and difficult to market.

Control
Spray diazinon 60EC plus white oil.

Red Banded Thrips

This is known by the scientific name selenothrips rubrocinctus. It attacks only young seedlings in the nursery

Diagnosis

Lower leaf surface is darkly stained, rusty appearance, with curled edges of leaves and numerous shiny black spots of excreta.

Control

Spray sumithion 50EC or fenitrothion

Mango Fruit Fly

Diagnosis

  • Premature ripening of fruit.
  • Flesh under the skin (which is the egg laying site) becomes liquid due to secondary infection.
  • Widespread fruit dropping

Control

  • Collect all fallen fruit put them in a drum of water with 1 inch of oil for 2 weeks
  • Burn them.
  • Bury them deep in the soil(2 ft)
  • Put them in tied plastic bags and expose them to the heat of the sun for a few days until the fruit is rotten and all the maggots in the bag are dead.
  • Spray trees with any of the following; Malathion or Dimethoate or labaycid

Note

Control is enhanced if the insecticide is mixed with an attractant/bait like molasses or sugars Other commercial baits such as nulure, buninal, solbait, GF120(Success). These baits are normally applied 1 m square spot on the canopy of each fruit tree on a weekly basis starting from when the fruits are 1 cm in size till the end of harvest

Gall midges

Diagnosis/symptoms

The adult lays eggs on tender leaves. Occurrence of “pimples” becomes necrotic and the leaves may drop

Control

  • Apply Malathion, Dimethoate mixed with white oil
  • The concentration of the white oil should not exceed 2% i.e 400ml for 20 lt of water. Higher concentrations are poisonous. Avoid application during hot periods of the day.

Diseases

Mango Powdery Mildew

Known by the scienfic name Oidium mangiferae.

Diagnosis/symptoms

  • Infected flowers, flower stalk, young fruits and leaves are coated with white powdery growth of the fungus.
  • Attacked fruits turn brown and shed prematurely.
  • Fruits fail to set if whole blossom is infected
  • It is common in cool and cloudy weather

Control

  • Spray Dinocarp from flowering to fruit formation stage at 2 weeks interval
  • Spray Benlate before flowering and again 3 weeks later
  • Culturally, avoid arranging seedlings in a nursery densely and prune tree canopy for improved air circulation.

Anthracnose

Attacks all tender parts of fruit and severe on the flowers, young fruits and leaves

Diagnosis

  • Black spots seen on fruits, flowers and leaves
  • Excessive flower and fruit drop
  • The black spots on fruits develop into depressions and the skin cracks and turns into black rots and penetrates into the flesh

Control

  • All dead twigs and leaves should be removed and destroyed
  • Spray with any of the following; Antracol, Kocide DF before and after flowering
  • Plant less susceptible varieties e.g. Tommy Atkins
Mango Anthracnose - appearing as black spots

Mango Anthracnose - appearing as black spots