When is top dressing and fertilizer saving for wheat?

When wheat enters the jointing stage, the stems and leaves grow rapidly, and the young ears differentiate and form, which is the period when wheat absorbs the most nutrients in its life, and the absorption of nitrogen, phosphorus and potassium begins to enter the peak period. Therefore, it is necessary to strengthen nitrogen nutrition, consolidate tillering years ago, improve tillering rate, cooperate with appropriate phosphorus and potassium nutrition, promote strong stalks, improve grain yield and ensure high and stable yield.

However, whether to apply jointing fertilizer, how much to apply and when to apply it have to be "three-watched".

As soon as you see the plots with poor seedling growth and fertilizer removal, you should apply green manure early and repeatedly. Generally, nitrogen fertilizer can be applied when the surface begins to thaw, such as 20-30 kg urea and 40 kg ammonium bicarbonate per mu. Wheat fields with good growth, dark green leaves and strong wheat seedlings can be applied with less or no nitrogen fertilizer and only phosphorus and potassium fertilizer, such as 20-25 kg of phosphorus and potassium fertilizer per mu.

Second, look at the soil fertility, fertile soil, wheat fields with sufficient base fertilizer, you can apply less or no nitrogen fertilizer, only some phosphorus and potassium fertilizer. The soil fertility is poor and the base fertilizer is insufficient, so more nitrogen fertilizer should be applied with phosphorus and potassium fertilizer.

At the jointing stage of wheat, topdressing should be done as early as possible at the jointing stage to save water for intercropping middle and low yield wheat, weak seedlings in late stubble in high yield wheat fields, weak wheat and old and weak seedlings that were not fertilized or promoted enough during the greening period. On the basis of controlling greening, jointing stage is generally the main stage of fertilizer and water for precision sowing and strong seedlings in high-yield wheat fields. In the wheat field with moderate or little fertilization in the early stage and no vigorous growth trend of wheat seedlings, fertilization should be early rather than heavy, and vice versa. For high-fertilizer and high-yield wheat fields, or wheat fields with good soil fertility, large individuals and prosperous trend lines, water can be applied later or less. Fertilizer and water should be controlled at jointing stage in single-stem cultivation of late rice.