Herbicide damage is mostly related to human factors; how can it be prevented?
In recent years, the area treated with herbicides and the amount applied have increased year by year, saving farmers time in controlling weeds, but due to human factors, improper application of herbicides has also brought adverse effects on production.
Improper storage, blind misuse
Because herbicides are stored improperly, packaging labels fall off or are corroded and become illegible, and the herbicide is mistakenly applied as an insecticide or fungicide, or it is applied without following the herbicide label instructions, causing damage. Prevention method: store herbicides properly and prevent packaging labels from falling off. If a label is found to be missing, immediately attach a new label stating the herbicide name and application method.
Excessive dosage, too high concentration
The application rate and concentration of herbicides are stricter than those of insecticides and fungicides. Each herbicide has a specified dosage; for example, excessive use of tribenuron-methyl can cause damage to wheat. Prevention method: strictly control the herbicide dosage and concentration.
Improper application method
Once a herbicide is applied improperly, it will cause damage. For example, when many herbicides are applied, they contaminate seeds and easily cause damage; when herbicides are sprayed near sensitive crops and in strong wind, a large amount of spray droplets drift onto sensitive crops and cause damage. Prevention method: choose different application methods according to the weeds, herbicide, and environmental conditions, and master the technical points for safe and efficient herbicide application. Improve application quality, clarify the plant parts on which the herbicide acts, ensure accurate timing of application, choose to apply on sunny and windless days, and avoid contaminating sensitive parts of crops or drifting onto nearby sensitive crops.
Blind mixing of pesticides
Mixing herbicides can improve the weed control effect, broaden the weed-killing spectrum, control diseases, insects, and weeds at the same time, save pesticide use, and have advantages such as saving labor, time, and money. However, if mixed blindly, it not only has no synergistic effect but instead reduces efficacy and causes damage. Prevention method: prohibit arbitrary and blind mixing of herbicides. Before mixing pesticides, conduct compatibility observation and tests for efficacy and damage. According to tests, common varieties that can reduce efficacy and cause damage after mixing include: propanil and organophosphorus and carbamate pesticides; mixing 2,4—D and thiobencarb; mixing quizalofop and bentazone; mixing MCPA and acidic pesticides; mixing fluazifop and bentazone, all of which can lead to damage.
Sprayer not cleaned thoroughly
If a sprayer that has been used for herbicides is not cleaned in time and is then used to spray other pesticides, it may cause damage. For example, after spraying MCPA and 2,4—D butyl ester, if it is not cleaned thoroughly, it easily causes damage to dicotyledonous crops. Prevention method: clean sprayers used for herbicides in time. The procedure is to first rinse with clean water, then wash repeatedly several times with soap or 2%—3% alkaline water, and finally rinse clean with clean water. It is best to use a dedicated sprayer for spraying herbicides.