When will wheat catch up with green manure? The seedling situation of winter wheat can be divided into two aspects: group and individual. When we look at the situation of seedlings, we should combine groups with individuals. If the wheat field belongs to the seedling situation with large population and strong individuals, its growth should be properly controlled first. We can use 15% paclobutrazol wettable powder 30-40g, 30kg water per mu, which can effectively control the vigorous growth of wheat seedlings.
Secondly, the topdressing time of this kind of wheat field should be postponed. When the wheat seedling grows to the second leaf, it is just right to apply fertilizer when the wheat ear divides into tetrads.
It is not good to topdressing wheat seedlings too early, and it is not conducive to the formation of yield too late.
For the late-sown and thin wheat, the length of the main stem internode of the wheat plant was fixed at the beginning of March, and fertilization was applied when the second internode was stretched, so that the stem internode would not be too long and the lodging resistance of the plant would be weakened.
How much fertilizer should be used for wheat topdressing? The amount of topdressing after winter wheat should consider soil fertility and the application of base fertilizer in the early stage of wheat field.
According to the actual situation of wheat field growth, the total amount of nitrogen fertilizer used in wheat growth period is generally about per mu 13kg. If the nitrogen content of base fertilizer has reached per mu 13kg, and the fertilization position is shallow (10cm), if the wheat field population is too prosperous, we can consider not applying nitrogen fertilizer or applying less nitrogen fertilizer.
Judging from the number of overwintering seedlings, the wheat field with yield below 400,000 ears per mu or single seedling wheat field is the focus of fertilization.
The specific amount of fertilizer used is as follows: 1. Before turning green, the total number of stems per mu should be less than 450,000, and the three types of wheat fields with light leaves and poor growth should be managed in time, and topdressing can be carried out twice in spring.
In the second greening period, topdressing 5-8kg urea per mu and watering; For the second time, 5~ 10 kg of urea was applied with water per mu at jointing stage.
2. Before turning green, the total number of stalks per mu was between 450,000 and 600,000, and the second-class wheat field population was small. At the early stage of wheat growth, combined with watering, topdressing urea 65,438+00 ~ 65,438+05 kg per mu.
3. Before turning green, the total number of stalks per mu is between 600,000 and 800,000, and the wheat fields suitable for the population can be watered in combination with jointing stage, with topdressing urea of 65,438+02 ~ 65,438+05 kg per mu.
4. Wheat fields with yield of more than 800,000 stems per mu, dark green leaves and vigorous growth before turning green should adopt intertillage inhibition, postpone the application time of nitrogen fertilizer and reduce the amount of nitrogen fertilizer, control the vigorous growth of the population, and prevent lodging, greed for green and late maturity.
Generally, urea can be topdressing 8~ 10 kg per mu in the late jointing stage.
5. Wheat frozen during the wintering period or the turning green period should be topdressing and watering according to the occurrence of freezing injury. For those with severe freezing injury, apply urea 5~ 10 kg and water immediately per mu to promote early tillering of wheat, improve tillering rate and reduce freezing injury loss.
6. Apply diammonium phosphate topdressing in the fields without phosphate fertilizer or lacking phosphorus.
It is suggested that nitrogen and potassium compound fertilizer should be applied at the greening or jointing stage, and no or less potassium fertilizer should be applied; It is necessary to combine the prevention and control of sheath blight with the measures of one spraying and three prevention, and compensate phosphorus and potassium fertilizer through topdressing outside the roots; If there is no irrigation condition or effective precipitation, urea and potassium dihydrogen phosphate can be sprayed on the leaves in spring to save water by fertilizer.
7. Potassium dihydrogen phosphate, boron fertilizer and zinc fertilizer can be sprayed on the leaves of wheat during grain filling to prevent dry hot wind and lodging, improve grain filling strength and increase grain weight.
8. In wheat fields in sulfur-deficient areas, if calcium superphosphate, potassium sulfate and sulfur-based compound fertilizer are not applied as base fertilizer, ammonium sulfate should be applied in the second topdressing, and the sulfur application amount per mu is about 2 kg.
9. Many farmers do not rake the ground after rotary tillage, resulting in deep sowing and weak seedlings, few tillers and weak seedlings. It is suggested that urea 10~ 15 kg should be applied topdressing during the greening period.
The above is the introduction of when the wheat returns to green fertilizer and how much fertilizer is used for topdressing. Want to know more about the agricultural resources market, you can pay attention to: WeChat WeChat official account: huobao3456tv for more information. You can also leave a message and reply to the industry information you want to know after paying attention.