Pests & Nutrient disorders

Nutrient Disorders

  • If the fruit has a hollow cavity and has poor taste, it might be due to potassium deficiency.
  • If the crop demonstrates stunted growth, delayed maturity and reduced yields it might be due to phosphorous deficiency.
  • If the crop show blossom end-rot it might be due to excess Nitrogen or Calcium deficiency.
  • If the crop show blossom end-rot and small size fruits it might be due to excess Nitrogen.

For nutrient disorders refer to your extension officer to get further advice

Pest Diagnoses

  • If there is swellings on the roots causing stunting of the plants and eventual wilting this is possibly due to Root Knot Nematodes
  • If there is sign of caterpillar damage characterized by bore into fruit and consumed inner part of the fruit with plenty of excreta, this is possibly due to American Bollworms
  • If you see small white moth-like flies fly from foliage when plants are disturbed.  Or notice leaf distortion and stunting this is possibly due to Tobacco White Fly.
  • If minute spider like animals are found on the underside of the leaves.  The leaves are tarnished and turned yellowish and whitish.  If infestation is severe plants show stunted growth, leaves dry up and falls off. The pest is possibly Red Spider Mites.
  • If you notice plant lice that sooty mould and distorted young leaves and flowers the problem is possibly due to Aphids

Scroll further down to read more on symptoms and control of the specific pest

Root Knot Nematodes

Symptoms

  • These include swellings on the roots causing stunting and yellowing of the plants and eventual wilting.

Control

  • Crop rotation.
  • Plant nematode free seedlings that is with no swellings on the roots.
  • Keep field free of weeds.
  • Use recommended nematicides

American Bollworms

Symptoms

  • The caterpillar bore into fruit and feed on the inner part of the fruit releasing plenty of excreta which is noticeable on damaged fruits.
  • The entry point of the caterpillar acts as entry point for bacteria and fungi.
  • It attacks sweet pepper, tobacco, sorghum.

Control

  • Use recommended insecticides

Tobacco White Fly

Symptoms

  • Small white moth-like flies fly from foliage when plants are disturbed.  The nymph sucks sap from underside of the leaves.
  • They transmit virus.
  • They cause leaf distortion and stunting if attack is early.

Control

  • Keep field free of weeds
  • Use recommended insecticides and spray the underside of the leaves.
  • Spraying should start from periphery moving towards the centre. Early morning or late in the evening.

Red Spider Mites

Symptoms

  • These are minute spider like animals found on the underside of the leaves feeding on the sap.
  • Whitish to yellowish specks cover the leaf surface. Under severe infestation fine webs will be found covering the leaf surface, there is also stunted growth, leaves dry up and falls off.
  • The problem is acute in dry areas or irrigated crops.

Control

  • Use recommended miticides.

Aphids

Symptoms

  • These are plant lice that suck sap from leaves causing leaf distortion especially during dry spells.
  • Aphids prefer young leaves, stems or flowers.
  • Their secretion causes sooty mould.  They transmit viral diseases.

Control

  • Spray with recommended insecticides

Leaf minor

Symptoms

  • A small caterpillar that burrows between the top and lower leaf lamina creating silvery tunnels on the upper leaf surface causing considerable damage to the leaves.

Control

  • Spray with recommended systemic insecticides