Control of the moth fly Tinearia alternata Say (Diptera: Psychodidae) in polyurethane substrate of hydroponic Welsh onions by hot-water treatment

Abstract

We investigated the control effect of hot-water treatment on the moth fly Tinearia alternata in a polyurethane substrate of hydroponic Welsh onions. We collected polyurethane substrate inhabited by T. alternata with Welsh onions from the field, squeezed it lightly to reduce its water content, and put it in hot water (48 or 50°C) for 1, 2, or 3 min. We then soaked it in cold water and held it at room temperature under an ambient photoperiod and counted the number of adults that appeared every day for 8 days. Hot-water treatment at 50°C for ≥2 min proved effective. No damage was observed on the green onions in any treatment.