Many spraying decisions in the field are driven by concern rather than calculation.
Seeing insects on plants often pushes some farmers to use an insecticide immediately, even though in many cases the infestation has not yet reached a level that causes real production loss.<\/p>\n\n\n\n
Here comes the concept of the economic threshold of infestation<\/strong>, the scientific benchmark that determines when intervention becomes necessary and when waiting is the smarter decision.<\/p>\n\n\n\n Understanding this concept forms the critical link between accurate diagnosis and building an integrated crop protection program based on informed decisions rather than haste.<\/p>\n\n\n\n First: What Is the Economic Threshold of Infestation?<\/strong><\/p>\n\n\n\n The economic threshold is the level of infestation at which the expected crop losses begin to exceed the cost of control.<\/p>\n\n\n\n In simple terms:<\/p>\n\n\n\n If the potential yield loss is greater than the cost of spraying \u2192 intervention is justified. This explains why not every presence of insects means you need to apply insecticides<\/a> immediately.<\/p>\n\n\n\n Second: Why Do Many Farmers Misjudge the Economic Threshold?<\/strong><\/p>\n\n\n\n A common mistake is confusing the presence of insects with the presence of real risk.<\/p>\n\n\n\n Finding three to five insects on a single plant does not necessarily mean the crop is threatened. Many cases of insecticide failure<\/a><\/strong> actually begin with unnecessary spraying, followed by selection pressure that later contributes to pest resistance.<\/p>\n\n\n\n Third: How Do You Calculate the Economic Threshold in the Field?<\/strong><\/p>\n\n\n\n The calculation does not require complex equations, but organized steps:<\/p>\n\n\n\n 1) Determine the Percentage of Infested Plants<\/strong> 2) Evaluate the Severity of Damage<\/strong> 3) Estimate the Cost of Control<\/strong> 4) Estimate the Potential Loss<\/strong> If the expected loss exceeds the cost of control \u2192 the economic threshold has been crossed.<\/p>\n\n\n\n Fourth: The Relationship Between the Economic Threshold and Pest Resistance<\/strong><\/p>\n\n\n\n Spraying before reaching the economic threshold increases the number of pesticide applications unnecessarily. Ignoring the economic threshold therefore not only increases costs but also accelerates the loss of control effectiveness.<\/p>\n\n\n\n Fifth: The Difference Between the Economic Threshold and the Critical Threshold<\/strong><\/p>\n\n\n\n The economic threshold is not the same as the critical threshold.<\/p>\n\n\n\n The critical threshold is the level at which damage becomes nearly irreversible.<\/p>\n\n\n\n If intervention is delayed until the critical threshold is reached, losses have already occurred.<\/p>\n\n\n\n This is why regular monitoring is essential within integrated pest management systems<\/a><\/strong>.<\/p>\n\n\n\n
If it is lower \u2192 spraying is unnecessary.<\/p>\n\n\n\n
However, if infestation exceeds 20\u201330% of the plants, the situation begins to change.<\/p>\n\n\n\n
Select 10 random sampling points within the field.
Inspect an equal number of plants at each point.
Calculate the overall infestation percentage.<\/p>\n\n\n\n
Is the damage superficial, or does it affect growing tips or flowers?
Is the infestation stable, or is it doubling daily?<\/p>\n\n\n\n
Pesticide price + labor cost + water cost + downtime.<\/p>\n\n\n\n
Will the damage affect total yield?
Will it affect crop quality?<\/p>\n\n\n\n
With repeated use of the same active ingredient, pest resistance to pesticides<\/a><\/strong> may begin to develop.<\/p>\n\n\n\n