BioWiki / Environment

Temperature — IPM driver (protected crops)

Temperature — IPM driver (protected crops)

Summary

Temperature is the primary accelerator of pest population growth in protected crops. The key risk is speed mismatch: pests respond immediately, while beneficials often lag.

What this driver controls

  • Development rate (generation time) and fecundity (rate of reproduction)
  • Mortality/survival at extremes
  • Crop growth tempo (flush speed) and tissue softness
  • Predator/prey synchrony (establishment timing)

Pest fingerprints

Thrips

  • Strong acceleration above ~22°C (especially in flowering crops).
  • Risk spikes when warmth coincides with flower initiation/flowering (resources + habitat increase).
  • Warm, stable houses + continuous cropping reduce “season break” → persistence.

Spider mite

  • Strong acceleration above ~20°C, especially when paired with high VPD (see humidity driver).
  • Outbreaks often feel “structural”: once established, populations can explode quickly.

Aphids

  • Strong acceleration ~18–24°C (often highest pressure in mild-warm conditions with soft growth).
  • Temperature amplifies the impact of vegetative flush: faster flush = faster colony expansion.

Beneficial stability / failure modes

  • Predator lag window: pests accelerate before beneficial populations build.
  • Heat + poor microclimate can reduce efficacy of some agents; extreme heat can harm establishment.
  • Timing: introductions after a warm step-change often arrive too late.

Monitoring signals

  • Daily min/max + range (ΔT), not just mean.
  • “Step-change” events: a sudden move from cool/dull to warm/bright.
  • Phenology coupling: temperature rise + new flush/flowers beginning.

Stabilising actions

  • Prioritise stability over chasing setpoints: reduce rapid swings.
  • Introduce key biocontrol ahead of forecast warm periods (pre-load the system).
  • Pair with VPD management: warm + dry is higher risk than warm + balanced.

Links