Safe Use Methods and Precautions for Rice Field Herbicides
How to Safely Use Herbicides in Rice Fields
(Agricultural Wealth Network) How to safely use herbicides in rice field production to avoid the occurrence of phytotoxicity problems? The following points should be grasped:
Choose the appropriate herbicide. Different herbicides should be selected for direct-seeded fields, seedling-throwing fields and transplanted fields, as well as for different growth stages such as the seedling stage and the peak tillering stage. The use methods and requirements of each herbicide are different; for example, some require a water layer, while others must not have a water layer. During specific operations, strictly follow the product instructions.
Master the appropriate application period and dosage. Weed seeds are sensitive to the chemical when they germinate and just emerge, which is the best time for application. While ensuring the safety of rice, apply the chemical promptly, and be careful to avoid sensitive periods prone to phytotoxicity, such as the young panicle formation stage and the flowering stage of rice. Strictly apply according to the product instructions; overdosing is prohibited, otherwise phytotoxicity will result.
Improve the application level. During application, spraying should be uniform; fine-mist spraying and fan-shaped spraying are advocated to reduce missed spraying and repeated spraying. Do not spray when it is windy, to prevent herbicide drift from causing phytotoxicity. After application, promptly clean the spraying equipment to ensure no herbicide residue remains. Promote the use of new application equipment to reduce the "running, bubbling, dripping and leaking" of the spray liquid; it is best to use separate equipment for spraying herbicides.
Take timely remedial measures when phytotoxicity occurs. Sulfonylurea herbicides such as bensulfuron-methyl are the type of herbicide that has caused the most phytotoxicity incidents and the greatest phytotoxicity losses in recent years. Safe application should be strengthened in production. For mild damage, immediately spray brassinolide, etc., to enhance the crop's stress resistance, while strengthening fertilizer and water management. For severe damage, promptly contact the technical department, carry out acid washing and deep plowing of the soil, and switch to crops that are not sensitive to this type of herbicide.
For phenoxycarboxylic acid herbicides such as MCPA, mild damage can generally be recovered in a short period by strengthening fertilizer and water management, spraying foliar fertilizer, and using hormone regulation with sodium sulfite, brassinolide, etc. For plots with relatively severe phytotoxicity, promptly deep plow and irrigate, and switch to crops that are not sensitive to this type of herbicide.
Bipyridylium herbicides such as paraquat and organophosphorus herbicides such as glyphosate are non-selective herbicides and are prohibited from use during the rice growing period. When controlling weeds on field banks, prevent drift from harming rice seedlings. If only some leaves of the affected rice seedlings show brown spots and the heart leaf has not died, part of the leaf loss can be compensated by strengthening fertilizer and water management; if most leaves and the heart leaf are damaged and the rice seedlings have basically died, promptly replant crops.
Choose the appropriate herbicide. Different herbicides should be selected for direct-seeded fields, seedling-throwing fields and transplanted fields, as well as for different growth stages such as the seedling stage and the peak tillering stage. The use methods and requirements of each herbicide are different; for example, some require a water layer, while others must not have a water layer. During specific operations, strictly follow the product instructions.
Master the appropriate application period and dosage. Weed seeds are sensitive to the chemical when they germinate and just emerge, which is the best time for application. While ensuring the safety of rice, apply the chemical promptly, and be careful to avoid sensitive periods prone to phytotoxicity, such as the young panicle formation stage and the flowering stage of rice. Strictly apply according to the product instructions; overdosing is prohibited, otherwise phytotoxicity will result.
Improve the application level. During application, spraying should be uniform; fine-mist spraying and fan-shaped spraying are advocated to reduce missed spraying and repeated spraying. Do not spray when it is windy, to prevent herbicide drift from causing phytotoxicity. After application, promptly clean the spraying equipment to ensure no herbicide residue remains. Promote the use of new application equipment to reduce the "running, bubbling, dripping and leaking" of the spray liquid; it is best to use separate equipment for spraying herbicides.
Take timely remedial measures when phytotoxicity occurs. Sulfonylurea herbicides such as bensulfuron-methyl are the type of herbicide that has caused the most phytotoxicity incidents and the greatest phytotoxicity losses in recent years. Safe application should be strengthened in production. For mild damage, immediately spray brassinolide, etc., to enhance the crop's stress resistance, while strengthening fertilizer and water management. For severe damage, promptly contact the technical department, carry out acid washing and deep plowing of the soil, and switch to crops that are not sensitive to this type of herbicide.
For phenoxycarboxylic acid herbicides such as MCPA, mild damage can generally be recovered in a short period by strengthening fertilizer and water management, spraying foliar fertilizer, and using hormone regulation with sodium sulfite, brassinolide, etc. For plots with relatively severe phytotoxicity, promptly deep plow and irrigate, and switch to crops that are not sensitive to this type of herbicide.
Bipyridylium herbicides such as paraquat and organophosphorus herbicides such as glyphosate are non-selective herbicides and are prohibited from use during the rice growing period. When controlling weeds on field banks, prevent drift from harming rice seedlings. If only some leaves of the affected rice seedlings show brown spots and the heart leaf has not died, part of the leaf loss can be compensated by strengthening fertilizer and water management; if most leaves and the heart leaf are damaged and the rice seedlings have basically died, promptly replant crops.