In the process of wheat growth, grass damage is difficult to avoid, and if weeding is not timely, the growth of plants will be slowed down, and the yield, quality and efficiency will be reduced.
With the development of wheat sowing in various places, weeding has once again become a real problem, whether to weed before winter or after winter, which troubles grassroots agricultural producers.
In fact, according to the planting practice, autumn weeding and spring weeding promote each other, autumn weeding makes wheat grow vigorously and safely through the cold winter, and spring weeding is to check and fill in the gaps and remove growth obstacles.
The common weeding methods in mainland China include physical and chemical, chemical weeding is more convenient, fast and efficient, and the precautions should be grasped in the process, and the principle of local application should be followed to ensure that the efficacy of the medicine is fully exerted.
In particular, in recent years, the application range of chemical herbicides has been expanding day by day, the resistance of some weeds has been enhanced, and the problem of pesticide damage has become prominent, so the scientific and rational use of herbicides has become more and more important.
Advantages of weeding before winter
The weed types in wheat fields are annual, over-annual, and perennial, and the weeds reach the peak of emergence before the emergence of wheat and overwintering.
Reduce the weed base. The wheat field has abundant water and nutrients before winter, and the emergence of weeds is large, which can account for 8-9 percent of the annual unearthed amount, and the weeds are young plants at this time, with thin stems and tender leaves, weak resistance to pesticides, and sensitive to herbicides.
During this period, spraying herbicides can be more targeted to eliminate weeds in the field, control the base of grass damage, and avoid the growth of pested weeds after spring, with the increase of temperature, the plants will be flooded, and the difficulty of extermination will increase.
High security attributes. Choose to spray herbicides before winter, the leaf area of wheat seedlings and weeds is small, the plants are not in contact with each other and shading, and the herbicides can directly and quickly contact weeds.
On the contrary, if the herbicide is sprayed again in spring, the wheat seedlings and weeds will return to green and develop, forming a shield between each other, and the liquid medicine can not be directly absorbed by the weeds, and the weeding effect will be reduced, and the interval will be too short, and the negative effect on the next crop can be avoided.
Promote safe winterization. In fact, most weeds and wheat have the same growth period and require similar nutrients.
It can effectively avoid weeds and wheat seedlings competing for nutrients and living space, promote wheat plants to be full of seedlings and strong seedlings, improve the ability of cold and frost resistance in the process of wintering, and avoid the problem of frost damage, resulting in weak seedlings and yellow seedlings, and the growth is hindered.
Weeding technical solutions
When choosing to spray herbicides before winter, it is necessary to formulate a complete weeding technical plan, such as the selection of spraying periods, the weed objects to be controlled and the spraying technology.
Spraying period selection. The temperature of each region is different, the grass conditions of each block are different, and the time of spraying pesticides is different, so it is necessary to choose the appropriate spraying time.
Under normal circumstances, after choosing the three-leaf stage of wheat, the spraying effect between the 2nd and 4th leaves of weeds is the best, because the spraying of herbicides before the 3-leaf stage of wheat seedlings is easy to cause pesticide damage, and the weeds enter the 5th leaf, and the herbicide resistance ability will be enhanced.
Prevent objects. The common types of weeds for weeding before winter are grasses, such as Kanmai Niang, wild oats and wheat, and broad-leaved weeds, such as pig weeds, camellia and Artemisia spp.
Among them, the shape of gramineous weeds and wheat is close, it is difficult to exterminate, and if you are a little careless, you will identify the error, so you should be careful to identify and master the method.
To judge the wheat lady, wild oats and wheat, first look at the base of the stem, which is purple red, that is, look at the wheat lady, whether it is white is wild oats and wheat, and then look at the foliage, wild oats with pubescence on both sides are wild oats, and hairless is wheat.
Spraying techniques. According to the morphology of weeds, select the corresponding herbicide with strong weeding spectrum, in order to reduce the number of spraying, it is necessary to appropriately delay the spraying time, most of the weeds are out of the house, and then spray, which can avoid multiple spraying and cause waste.
It should be noted that the temperature of spraying herbicides can not be too low, low temperature environment, spraying pesticides to 15-20 days, or even 30 days to reflect the effect of extermination, below 8-10 °C, the activity of the pesticides is weakened, and the spraying effect is discounted.
At the same time, it should also be noted that if organophosphorus and carbamate pesticides have been sprayed, herbicides should be sprayed at intervals of 7 days, which reduces the ability of wheat to reduce herbicides, resulting in yellowing of plant stems and leaves, and the problem of seedling burning.
Precautions
In the process of spraying herbicides, do not spray blindly at will, and clarify the common precautions, the adverse effects of non-standard spraying and the solutions to pesticide damage.
Control the amount of herbicide. According to the instructions for the use of herbicides, standardize the dosage and concentration of herbicides, the dosage is too small, the efficacy is poor, the weeding effect is not ideal, the dosage is too large, and the agent is wasted.
In the process of spraying herbicides, it is necessary to spray evenly, do not miss spraying, repeat spraying, miss spraying and spray wrongly, the control effect is not ideal, and wheat plants are prone to pesticide damage and yellowing.
Proper disposal of medicines and devices. The equipment used to spray herbicides should be inspected before spraying to avoid foaming, bubbling, dripping and leaking in the spraying process, resulting in uneven spraying of the liquid medicine.
After spraying herbicides, they should be thoroughly cleaned with water to avoid residual herbicides in the later use of pesticides and equipment, which threaten the growth process of other types of crops.
Pay attention to moisture and weather. The use of most herbicides should be good, 40%-60% of the moisture state is most suitable for spraying herbicides, and if the moisture is too poor, it should be combined with wheat field irrigation and spraying herbicides.
On the one hand, on the one hand, the liquid medicine is scattered with the wind, endangering other crops, and the liquid medicine is lost with water in rainy days, and the weeding effect is reduced; On the other hand, there is a drug injury.
Herbicide damage has appeared, and soon after the spraying time, water can be sprayed, dilution of the agent, and pesticide damage can be alleviated. At the same time, if the growth of wheat plants is slow, it can be combined with plant growth regulators to promote the recovery of growth.
Finally, no matter when you choose to spray herbicides, you must remember to choose the right type of herbicide, standardize the use of drugs, use drugs scientifically, improve the spraying effect of herbicides, and control the reproduction and expansion of weeds.
If you don't want to use herbicides, grassroots producers who are idle at home can choose manual weeding, which can not only avoid pesticide damage, but also save planting and production costs and improve economic benefits.