What conditions favor rapid population growth of two-spotted spider mites?

• A. Hot, dry weather.
• B. Cool, damp weather
• C. Cold, windy weather
• D. Humid, mild weather with frequent rain

Answer: (A)

Hot, dry weather favors rapid population growth of two-spotted spider mites. Higher temperatures speed up their metabolism and shorten the time from egg to mature adults, so more generations can occur in a season. Dry air and leaf surfaces with low moisture reduce the effectiveness of plant defenses and can stress plants, making them easier for mites to feed on and reproduce in higher numbers. Dry conditions also help mites by limiting fungal pathogens and some natural enemies that would otherwise help keep populations in check.

In cooler, damp or windy conditions, mite development slows, and survival is reduced. Cool or wet weather slows their life cycle and can boost fungal diseases and predators that help suppress mites. Humid, mild weather with frequent rain tends to keep mite populations in check because moisture supports predators and fungi that attack mites, and rain can physically wash mites off leaves.