Pest Management Concepts by HC121104002213


									Pest Management Concepts (2)
   Study of the relationships between pest
    numbers, host responses, and resultant
    economic losses

   Connects biology and ecology with
    sampling and identification of the pest
                            Theoretical Natural Pest Population

Economic Losses
                                                  Economic Injury Level
Noneconomic Losses
                                                  Damage Boundary

 No Loss
          The EIL concept
 Economic damage: amount of injury which
  requires intervention
 Economic injury level: lowest population
  density that will cause economic damage
 Economic threshold: density where an
  intervention should occur to prevent the
  population from reaching the EIL
             Decision Making
   The Economic Injury level
    – EIL = C/VIDK
    – Where C = cost of the management tactic, V =
      market value of the produce, I = injury per
      insect, D = damage per unit of injury, K =
      proportion reduction in pest injury or damage
              Decision Making
   The Economic Threshold (the action
    – Based on:
       » pest and host phenology
       » Population growth and injury rates
       » Time delays associated with intervention tactic
               Types of ETs
   Subjective: based on experience, not
    formulated from objective criteria

   Objective: based on calculated EILs, change
    with the EIL
              Types of ETs
 Fixed: ET is set at a fixed % of the EIL
 Descriptive: a description of population
  growth is made and timing of the
  intervention is based on expected future
 Dichotomous: based on statistical
  procedures for classifying the population as
  economic or noneconomic. Based on a time
  perspective rather than a space perspective.
          Predictive Models
 Predictions are important because only
  future losses can be prevented
 Rate of insect growth is determined by
  temperature and moisture
 Could also simulate what may occur
  without intervention
       Cost-Benefit Calculations
   Intervention is cost effective only if the
    value of the commodity minus the cost of
    the intervention (+ sampling costs) is
    greater than the value of the commodity
    without intervention
       Preventive vs. Responsive
   Preventive: Prevent the development of the
    population (exclusion, sanitation, impact
    machines, and stock rotation)

   Responsive: based on estimated density
        Intervention in Response to
   Treat only the areas that need to be treated
    instead of the entire facility
    –   Farm bins
    –   Elevators
    –   Food processing
    –   Flour milling
     Effectiveness of Intervention
   Sampling programs should evaluate the
    effectiveness of the intervention

   Few interventions are 100% effective
   An approach to pest control that uses cost-
    benefit analysis in making decisions

   Pest control is cost-effective when the cost
    of control is less that the reduction in
    market value due to the pest

                   Start of Intervention
Population Size



To top