Causes and Control Countermeasures of herbicide damage in Paddy Field

Causes and Control Countermeasures of herbicide damage in Paddy Field

1 cause of occurrence

1.1 use of herbicides

1.1.1 wrong selection of herbicides herbicides containing butyl benzyl should be used in seedling throwing fields. If the herbicides in transplanting fields are used in seedling throwing fields, that is, herbicides containing ethyl benzyl components are used in seedling throwing fields, it will cause drug damage in seedling throwing fields. In recent years, one of the reasons for the serious damage of herbicides in paddy fields in Ji'an is that some pesticide manufacturers misused ethylbenzyl in the formulation of special herbicides in seedling throwing fields. In addition, some fake and inferior herbicides added metsulfuron and so on, which are also easy to cause drug damage.

1.1.2 improper use of herbicides includes the following situations: the dosage of 667 m2 exceeds the standard dosage; the water retention in the field is too deep after application, flooding the growing point and leaves, and it is easy to cause drug damage; the use time is too early, herbicides are easy to be used within 4 days after transplanting (throwing), uneven application and excessive application are easy to cause drug damage, and so on.

1.1.3 residue and accumulation of herbicides in soil herbicides containing metsulfuron-methyl degraded slowly in soil and could be residual and accumulated in soil. At present, in order to reduce costs, some manufacturers still partially use metsulfuron-methyl in the production process, while some farmers lack awareness and continue to use it. Years of accumulation caused drug damage in some fields that did not apply herbicides.

1.2 the weather causes heavy rainfall, flooding seedlings in the paddy field, less rainfall, continuous evaporation of water in the field, low water level, and herbicides injuring the roots. The temperature is high, the water evaporates quickly, the newly moved (thrown) seedlings do not adapt, and are vulnerable to drug damage [1].

1.3 other reasons

1.3.1 the seedling throwing field is easy to suffer because the seedling age of the seedling is young and sensitive to herbicides, and the seedling is tilted and the growth point is flooded in water, so it is more vulnerable to drug damage than the transplanted seedling.

1.3.2 improper use of drugs in seedling fields, some rice fields showed improper use of herbicides, resulting in drug damage in the field.

1.3.3 the sad leaves of the seedlings in the uneven and low-lying parts of the field were damaged by drugs, and the roots of the seedlings were not damaged by water in the high and convex parts of the field [2].

2 prevention and control measures

2.1 the use of herbicides with high residues should be strictly prohibited from the production, sale and use of herbicides with slow degradation and high residues such as metsulfuron-methyl in rice fields.

2.2 herbicides should be selected and used correctly after rice transplanting (throwing) 5 ~

After 7 days, the herbicides containing ethylbenzyl were selected in transplanting field and butyl benzyl herbicide in seedling throwing field. The dosage of 667m2 was mixed with about 10 kg of dry fine soil (or a certain amount of urea), and the shallow water layer of 3 ~ 5 cm was kept in the field for 5 ~ 7 days after application. Proper water level should be maintained in the paddy field after the application of herbicides. The application of herbicides should be reduced or not in sand and mud fields or leaking paddy fields.

2.3 to improve the level of cultivation techniques, to improve rice cultivation techniques, it is necessary to ensure that rice fields are ploughed and raked flat; seedling throwing is operated according to technical requirements to make the seedlings stand upright as far as possible [Jishan Huayao].

3 remedial measures

3.1 drain the field water first, replace it with clean shallow water, keep it for a day or two, and then replace it for two or three times.

3.2foliar fertilizer 667m2 was sprayed evenly with 20 ~ 40 mL of green agrochemical or 40 mL of rice disease resistance and yield increasing ling, and 30 kg of water. If yellow leaves appear in the later stage, green agropin or potassium dihydrogen phosphate [Jishan Huayao] can also be sprayed.

Apply black and white ash 667 m2 evenly for 30 kg (25 kg plant ash plus 5 kg quicklime, mix well), and replace toxic substances with active substances [5].

3.4.After 7-10 days of application, phosphate-potassium fertilizer or compound fertilizer could be applied properly for 5-10 kg, but urea could not be applied.

After remediation, the drug damage can be alleviated or eliminated after a week or two, and most of the seedlings can return to normal growth. If the rice fields where the drug damage is too serious and the seedlings are about to die and cannot be remedied, the rice fields should be washed and ploughed and replanted in time.