Pest Management, Crop Protection, and Integrated Pest Management
Core concepts
Understand the IPM philosophy: prevention, monitoring, economic threshold, and the integration of cultural, biological, physical, mechanical, and chemical tactics. Know the economic injury level and economic threshold concepts and how they guide spray decisions. Distinguish pest categories-insects, weeds, pathogens (fungi, bacteria, viruses), nematodes, and vertebrates-and their management tools. Understand pesticide classification (insecticide, herbicide, fungicide), modes of action, formulation, and the critical issue of resistance management through mode-of-action rotation. Know the principles of biological control (predators, parasitoids, pathogens) and the risks of broad-spectrum products to natural enemies.
Traps in questions
Do not equate economic injury level with economic threshold; the threshold is the action point set at or below the injury level to prevent it being reached. Remember that herbicides do not control insects and that mode-of-action rotation is the key resistance strategy, not merely alternating brand names. Watch for questions confusing selective versus nonselective herbicides and pre-emergence versus post-emergence timing.
Worked example
A field has 3 pests per plant; the economic threshold is 5 per plant. No action is warranted yet, but monitoring should continue. Rule of thumb: treat only when the pest population reaches or exceeds the threshold, and re-scout after treatment to confirm efficacy.
Rule of thumb
IPM decision sequence: identify, monitor, compare to threshold, choose the least disruptive effective tactic, then evaluate.