Pay attention to less phosphorus and more potassium in fertilizing wheat

First of all, the partial application of phosphorus to wheat is to increase the cost. Diammonium is quite expensive this year, with 64% of its retail price exceeding 3900 yuan per ton. Phosphorus is necessary, but there is no need for excess. Empirical data show that if 40-50 kg of ternary compound fertilizer containing 15% pure phosphorus is used as base fertilizer per mu, there will generally be no phosphorus deficiency.

Partial phosphorus application caused soil consolidation, some trace elements were fixed, and element deficiency occurred seriously. Because the phosphorus that can not be absorbed by wheat will be enriched in the soil, and its phosphate ions combine with the cations of trace elements such as calcium and magnesium in the soil to form insoluble phosphate, which not only wastes phosphate fertilizer, but also destroys the soil aggregate structure, resulting in soil consolidation. Therefore, do not apply phosphate fertilizer on the base fertilizer (such as diammonium phosphate).

When applying phosphate fertilizer, the ternary compound fertilizer with higher phosphorus content was selected on the base fertilizer, and the phosphorus was applied at one time. For example, Shandong and Hebei winter wheat areas can choose 40-50 kg / mu of 20-20-5, 20-20-7, 20-20-8, 20-20-10 and 22-14-10, 25-13-10, 27-12-10, 27-13-10 and other 40-50 kg / mu.

When diammonium and low-nitrogen and high-phosphorus compound fertilizer are used in the base fertilizer, in addition to 30-40 kg per mu, urea should be increased by 10 kg per mu to prevent the yellow phenomenon caused by straw rot and nitrogen competition between seedlings.

Since 2008, potash prices have skyrocketed, resulting in less and less potash application in agricultural production. This situation has been going on for nearly 4 years, and the lodging of summer corn and winter wheat in North China has increased in the past two years, which shows that potassium supplement has become very important to some extent.

The straw returned to the field can provide some potash fertilizer. If 40-50 kg ternary compound fertilizer is used on the base fertilizer per mu, it is not necessary to choose the formula with particularly high potassium content of 19-19-19 and 18-18-18. First, fertilizers with high potassium content are particularly expensive this year, increasing costs; second, potash fertilizer is too much to use, and it is too wasteful.

It is suggested that the high-nitrogen and high-phosphorus ternary compound fertilizer with about 7% potassium content should be selected as the base fertilizer, with a dosage of 40-50 kg / mu, such as 20-20-7, 20-20-8, 20-20-10 and so on. In the period of returning to green after 2000, a nitrogen-potassium binary compound fertilizer with a potassium content of 5% Mo 10% was selected as topdressing, with a dosage of 20-30 kg / mu, such as 30-0-5, 30-0-10, and so on. The application of potash fertilizer in two times can also improve the utilization rate of potash fertilizer and ensure disease resistance, lodging resistance and high yield.