When is the best time for weeding winter wheat? What kind of herbicide do you choose? How can I play well?

At present, winter wheat planting area, wheat sowing is under way, in a few days, wheat field weeds will slowly emerge, winter wheat weeding, need to pay attention to methods, reasonable time must be able to suppress weeds, winter wheat spraying herbicide when? What do winter wheat herbicides need to pay attention to?

There are two best times to weed winter wheat.

The temperature is lower than 6℃, and the medicine cannot be applied.

The best period for controlling wheat seedling is in the seedling stage (middle and late November), and the best period for controlling weeds in wheat field is in the green stage (late February to early March).

It is a good choice to control weeds in wheat seedling stage (middle and late November). At this time, weeds are relatively young, and their resistance to pesticides is relatively small. It is easier to control weeds. The dosage of pesticides is not too large.

Rejuvenation period (late February to early March) is also the best time to control weeds. However, at this time, weeds are older and more resistant to drugs. Therefore, it is necessary to increase the dosage of drugs when controlling weeds. In this case, the cost of drugs will be increased invisibly.

At the same time, there is also a disadvantage that it is easy to cause phytotoxicity to wheat, subsequent crops and neighboring crops. Although this period can also control weeds in wheat fields, special attention should be paid when applying pesticides.

Finally, to remind everyone, wheat weeding should pay attention to the weather temperature and humidity, when applying medicine, the average temperature should be higher than 6 degrees, and in the morning to 3 pm around the best, if the soil is relatively dry, should pay attention to increase water consumption, if there is water, it will affect the efficacy of wheat herbicides play.

Therefore, when applying wheat herbicides, we should seize the opportunity, consider many aspects, and apply them in time to lay the foundation for high yield of wheat.

Occurrence law of weeds in wheat field

There are two peaks of weed occurrence in wheat field, the first one is 30-40 days after wheat sowing, and the second one is before jointing of wheat in the following year. Generally speaking, most of the grass weeds sprout before winter, basically growing at the same time as wheat seedlings, such as brome, tauschii, etc., weed seedlings and wheat seedlings are very similar, difficult to distinguish. Broadleaf weeds mostly occur in spring and are easily distinguished from wheat seedlings.

Critical period of weed control in wheat field

According to the occurrence law of weeds in wheat field, there are two critical periods for their control.

One is pre-winter control, mainly to control grass weeds, about in early November, wheat growth 4-5 leaves, weeds generally grow for 2 leaves and 1 heart, at this time the best control effect.

The second is spring control, mainly controlling broadleaf weeds, the time is from late February to early March, the control period should be early rather than late, too late weed control is difficult, and wheat may cause phytotoxicity.

Suitable herbicides and formulations

The herbicide selected for chemical weeding in wheat field should be determined according to the main weed species and herbicide control spectrum. When the weed species in the wheat field are within the scope of the same herbicide, a single herbicide can be used for control; when several weeds are mixed, such as dicotyledonous weeds and monocotyledonous weeds, several herbicides should be mixed according to a certain proportion to expand the herbicide spectrum and improve the weeding effect. Several weed control formulas are provided below according to weed community types in Beijing wheat fields.

For wheat fields dominated by broad-leaved weeds such as Artemisia, Shepherd's purse, Maijiagong, Iongrass, Humulus, Chenopodium, etc., 10% tribenuron-methyl wettable powder can be selected at a dosage of 10g per mu, or 75% tribenuron-methyl water dispersible granules at a dosage of 1g per mu.

For wheat fields dominated by brome, 70% fluazuron-methyl (biaohu) water dispersible granules can be selected, and the dosage per mu is 3-4 g.

In order to beat the bowl flower-based wheat field, you can choose 20% chlorfluroxypyr (so that it long) EC, 50-70 ml per mu dosage.

For wheat fields dominated by Alopecurus and Echinochloa, 10.8% fenoxapyr (Puma) EC can be selected, and the dosage per mu is 30-40 ml, or 15% propargyl (wheat) WP can be selected, and the dosage per mu is 30-40 g.

For wheat fields mixed with brome and broadleaf weeds, 3-4 g of 70% fluazuron-methyl water dispersible granules +10 g of tribenuron-methyl wettable powder can be mixed per mu.

The above formula is mixed with 30- 40kg water per mu and evenly sprayed by hand pressure sprayer or spraying vehicle.

Technical requirements for application

Accurate medication. Herbicide should be sprayed according to the recommended dosage, and it is forbidden to increase or decrease the dosage at will to ensure the control effect and eliminate the occurrence of phytotoxicity.

Mix and use. When several herbicides are mixed and used, the secondary dilution method should be adopted, that is, the herbicide is dissolved in a small amount of water to form mother liquor, and then the mother liquor is diluted to the prescribed amount of liquid medicine. The mixed liquid medicine cannot be stored for a long time, and it should be applied at one time.

Select suitable climatic conditions for application to reduce drift and evaporation. In addition, most herbicides are PTCs and should not be applied at temperatures below 10 ° C.

Do a good job in the maintenance of drug application equipment. Before application, drug devices should be maintained in time to prevent running, emitting, dripping and leaking during application, so as to achieve uniform application.

Be safe. The pesticide application personnel shall take good safety protection. Smoking and eating are prohibited during operation to prevent poisoning accidents.