HOT-WATER TREATMENT AND COLD STORAGE TO CONTROL THE BULB MITE RHIZOGLYPHUS ROBINI ON LILY BULBS.
To reduce the dependence on chemicals, other potential control measures were investigated. Experiments with hot-water and cold-storage treatments of mite-infested lily bulbs showed that 98 – 99% of the mites were killed when the bulbs were dipped in water for 2 hours at 39°C or 41°C, and that more than 99% were killed after a storage period of 6 months at -2°C.
Infested bulbs were either hot-water treated or not and scales from these bulbs were put in plastic bags with moist vermiculite (temperature 23°C and high relative humidity) to induce adventitious bulblet formation. Surprisingly, scales and bulblets from hot-water-treated bulbs became more severely infested by the mites than those from untreated bulbs. The predatory mite Hypoaspis aculeifer, which was present on the bulbs and killed by the hot-water treatment, may have been responsible for this phenomenon.