Bean seed fly
can attack crucifers, cereals and tubers worldwide. Adult flies lay eggs near the base of bean plants, and upon hatching, the larvae burrow into the soil [...] and can cause significant damage. Presence of larvae: Small, white maggots near the base of affected bean plants. These larvae are a clear indicator of bean [...] The larvae, on the other hand, are small white maggots that can be found near the base of affected bean plants. You can recognise if your crop is affected