What do you know about herbicides in wheat fields?

What do you know about herbicides in wheat fields?

1. The best stage for wheat weeding: Practical experience proves that it is best to weed wheat fields before winter! As long as the wheat reaches 3 leaves and the temperature is above 5-8 degrees, the weeding effect will be best. The main reason is that the weeds in the wheat field have usually emerged at this time (in fact, some grasses emerge faster than the wheat), the weeds are smaller, and they are relatively sensitive and less resistant to herbicides. At the same time, at this time Because the weeds and wheat seedlings are small (the seedlings are not full in the field), they have sufficient adhesion to herbicides. Therefore, the effect of weeding before winter is better and the cost is the least. Many agricultural experts and the relevant technical implementation opinions of the Anhui Provincial Committee of Agriculture have clearly pointed out the necessity of weeding during this period. However, farmers may be accustomed to weeding only gradually in spring. Regulation: Even if wheat fields are not weeded now, farmers are requested to spray pesticides as soon as possible in early spring when the temperature reaches the above standards.

2. The primary factors that harm the effectiveness of herbicides

1. Harm during the weeding stage. You may have noticed that many herbicides in wheat fields where weeding and spraying are used during the middle and late stages of the wheat seedlings turning green and heading will not even show any effect after being applied. Once the weeds are suppressed, they will become green again. This situation does not It’s not just two families in one family, but almost all of them. At this time, even if you use two large bottles of gelding for one acre of land, the effect will not be good! The main reason is not that the herbicide is fake, but that the resistance of the weeds has increased at that time, and its rhizomes are more developed and the resistance to regeneration function greatly weakens the effect of the herbicide.

2. After the weeds become larger, the leaves of the weeds and the leaves of the wheat block each other. The total amount of weeds and wheat in the field with slightly more wheat grass is approximate. The water flow used by farmers to spray medicine is And the dosage of pesticide is too small (even one acre of field and one bucket of water), resulting in poor weeding effect. No matter how good the herbicide is, how can it be effective if the weeds cannot fully absorb the herbicide because it is blocked by the wheat leaves? At the same time, the demand for water increases, and the demand for herbicides should also increase at the same time.

3. Changes in the grass phase of weeds in wheat fields (weed types). Farmers encountered in the store said that the herbicides purchased in the store were not very effective. After observing the fields themselves, they found that the main type of weeds is wormwood (the final seeds are spindle-shaped) and they are sprayed after spring. The medicine, Puma often fails to treat it, and the field eventually severely limits production.

Fourth, there is also a situation: after using the herbicide for a period of time, it appears that the wheat field grass has not been killed, and many of them are green, but in fact, compared with other wheat fields without herbicide, or Compare the same weeds in the field without any treatment. It can be seen that the weeds that have been treated with herbicides have stopped growing or appear to be slower. This involves the concept of "biomass control effect" in crop protection. The number of weeds defeated is the definition of plant control effect. Another important indicator of weeding effect is "biomass control effect". This is because on the surface, some weeds are not dead, but the weeds have stopped or are slow to grow. Their growth will be quickly obscured by the growth of wheat. Generally, they will not cause much damage in the later stages. Herbicides are actually effective. of. The above situation occurs when herbicides are applied shortly after heading.

The main weeds in wheat fields in our field are field bindweed (also known by farmers as chickweed, March yellow grass, and cobweed). Weeds can be clearly identified when they bloom in the middle and late stages, but we must pay attention. The one with milky white anthers is Japanese field bindweed, and the one with yellowish anthers is Japanese field bindweed. Tanaka Japanese wheatgrass has better drug resistance, so the dosage should be increased when applying (in fact, farmers cannot distinguish between the two types during the spraying stage. Grass)

5. The harm of other factors to herbicides.

Generally, farmers are required to spray pesticides on early wheat seedlings in an appropriate amount compared with tap water. If too much water is used, it will drench the seeds, and the herbicide chlorogenic acid cannot be used and the effect will not be very good. The most important thing when applying medicinal value water in the middle and later stages is not to use less water, and the dosage cannot be too small. When the temperature is low, wheat and weeds hardly grow and develop, and the digestion and absorption of herbicides by weeds is slow. At the same time, part of the herbicide adhered to the leaves will volatilize and flow out, ultimately affecting the weeding effect.

The herbicide quinoxazole and thiocarbide (horse type) is on the market for wheat fields. This kind of herbicide should be sprayed after spring, especially after the wheat seedlings stand up, and it will kill bluegrass, bluegrass, and bluegrass. Hard grass and Miscanthus have almost no effect! This is my social experience, and I express it here.