1. Spraying. Dilute 48% chlorpyrifos emulsifiable concentrate with water and spray.
(1) Use 800-1000 times dilution to control larvae of American serpentine leafminer, leaf miner, and cabbage leafminer.
(2) Use 1000 times dilution to control larvae of cabbage caterpillar, beet armyworm, lamprey, melon leafminer, and aquatic stem borers.
2. Root Drenching. Dilute 48% chlorpyrifos emulsifiable concentrate with water and drench the roots.
(1) Apply 3.75–5.63 liters of emulsifiable concentrate per hectare with irrigation water to control root maggots.
(2) Apply a 2000-fold dilution to the plant roots by watering to control earthworm infestation. Use 3750–4500 liters of solution per hectare.
3. Soil treatment.
Apply 30–60 kg of 3% chlorpyrifos granules per hectare in furrows, holes, or by broadcasting before sowing or transplanting to control leek maggots, grubs, cutworms, etc.
