大だい発はっ生せい

noun

explosive increase; severe outbreak; upsurge of pests

Used especially for a sudden, large-scale increase in pest populations such as insects or rodents.

• 今年ことしはカメムシが大だい発はっ生せいして農のう作さく物ぶつに大おおきな被ひ害がいが出でた。

  This year there was an explosive increase in stink bugs, causing major damage to crops.