Annual weeds in winter rapeseed fields compete with the crop for water, nutrients, and light, and fields with severe weed infestations show significant yield losses. Herbicide selection for weed control depends on the target annual weed species and accurate identification of their growth stages—metazachlor 500 g/L SC (suspension concentrate) is registered for the control of annual weeds in winter rapeseed fields.
For annual weeds in winter rapeseed fields, the herbicides used for grasses and broadleaf weeds differ, and the application methods also vary between pre-emergence and post-emergence treatments. Soil-residual herbicides should be applied after sowing but before crop emergence, forming a herbicide film over the soil surface. For post-emergence foliar treatments, spray directionally when weeds reach the 3–5 leaf stage and when the crop is relatively safe.
Metazachlor 500 g/L SC (Suspension Concentrate), Registration No. PD20151577 (subject to the actual label). Used for the control of annual weeds in winter oilseed rape fields at a rate of 80–100 mL per mu, applied as a soil spray. Dilute with water according to the weed spectrum and crop growth stage, and spray evenly. Take care to avoid spray drift onto the crop.
For stem and leaf herbicide application, lower the nozzle and spray only the weeds to prevent spray drift from reaching the crop and causing injury; do not spray on windy days or before rain. Dosage varies significantly among different formulations—conduct small-scale trials first before large-scale application. Always follow the label instructions.
