Parashas Bo · Passuk 10:14
Chabad.org — English translation + Rashi
Torah Temimah points to Tanna de-Vei Eliyahu Rabbah 7 (verified).
English: Why did the Holy One, blessed be He, bring the plague of locusts upon them? Because they made Yisrael sowers of wheat and barley and all kinds of legumes; therefore He brought locusts upon them and destroyed everything that Yisrael had sown for them.
In context: See the cited source for the full section.
Derash on the verse (midrash) — measure-for-measure correspondence between the forced agricultural labor and the destruction of the crops.
The locust plague answered the forced sowing imposed on Yisrael: what the Egyptians made them plant was consumed by the locusts.