Thursday, 5 July 2012

Integrated pests management (I.P.M)

Integrated pests management refers to a wide range of tactics to prevent pests of all kinds from reaching damaging levels in plants. Pests can be  insects, mites, diseases, weed or vertebrates such as birds. Integrated management involves use of a combination of the following methods/tools.
Biological control
  • Predators for integrated management: e.g. use of ladybird to control of predatory mites, mites, whiteflies, aphids etc.
  • Parasites :parasitoid such as parasitic wasp
  • Pathogens: e.g. use of fungus Bauveria bassiana to control banana and sweet potato weevil, a bacteria Bassillus thuringiensis is used in control of lapidopteran larvae
  • Biological agents can be commercially prepared such as swirski mite, spical, spidex, ercal etc.  

Cultural Control
This involves use of agronomic practices that are designed to optimize crop growing conditions and increase the competitive edge. This results in increased tolerance and reduced chemical use. The cultural methods include:-
·        Crop rotation: this works by reducing the levels of pests attack due to rotation with non susceptible host.
·        Selecting resistant plant varieties: This helps to reduce severity of the attack in integrated management.
·        Cultivation/tillage practices
·        Variation of planting or harvesting dates: e.g. delayed planting in sunflower to reduce the sunflower beetle densities as integrated management measures.
·        Plant spacing: narrower row spacing favours development of diseases, due to environmental conditions within the canopy.
·        Fertilization level: a crop with a balanced fertility  levels  has a greater capacity to compete with weeds
·        Sanitation: Cleaning out storage areas helps prevent infestation of stored grain. Use of clean farm equipments and clean soil helps prevents spread of nematodes
·        Planting pests’ free seed or using seed treatment with a fungicide will help protect germinating seed and seedlings from seedling blight.
·        Planting trap crops: This consists of a surrounding field margin. The margins flower earlier and attract the insects concentrating them in a small area which reduces the cost of insecticide and the time required.

Plant resistance control
Classical selective breeding or genetic modification is used for integrated manament leading to a plant that is resistant, no longer preferred by the pests or creates an adverse effect.

Chemical control
This involves use of chemicals for integrated control. However they should only be used as a last result and when preventative and all other management techniques have failed, or are no longer economical. They also should be used in a manner that is legal considering rate of application, target crop etc.

Physical or mechanical control
This involves use of machinery or other tools for integrated management e.g.  
  • Tillage-Row cultivation can be used as a stand alone weed management practice or in conjunction with herbicide program.
  • Physical barriers e.g. mulching.
  • Exclusion using screens or barriers, preventing the pests from reaching and destroying crops/grains.
  • Trapping, suction devices such as pherohormone traps, can be used in integrated management to catch insects, sticky traps and light traps.
  • Use of heat in soil sterilization for control of nematodes and other plant pests