Problems that should be paid attention to in fertilization of vegetables prone to drug damage due to improper fertilization

Fertilization for vegetables

1. Ammonium nitrate application: green leafy vegetables such as Chinese cabbage, Chinese cabbage, amaranth, celery, spinach, etc., have a short growth period and are easy to absorb nitrate nitrogen fertilizer, resulting in excessive nitrate content in vegetables, so it is not suitable to apply ammonium nitrate.

2. Spraying pure nitrogen fertilizer: green leafy vegetables should not be sprayed with nitrogen fertilizer such as urea or ammonium sulfate, nor should they spray human urine. When urea, ammonium sulfate and human urine are sprayed on the leaf surface, the content of nitrate will increase, affecting human health.

3. Urea can not be irrigated immediately after applying urea: only under the action of urease secreted by soil microorganisms, urea can be transformed into ammonium carbonate or ammonium bicarbonate that can be absorbed and utilized by vegetable roots, or can be absorbed and preserved by soil. If the urea is irrigated or drenched in rain immediately after urea application, amide nitrogen will be lost with the water, resulting in nitrogen loss. The unnecessary loss of nitrogen can be avoided by irrigating water after applying urea 5mer for 7 days.

4. Ammonium sulfate should not be applied repeatedly: in acid soil or calcareous vegetable field, continuous application of ammonium sulfate will change acid soil, cause calcareous soil consolidation and hinder vegetable growth.

5. Ammonium bicarbonate is not suitable for lack of water in vegetable field: ammonium bicarbonate is very unstable and easy to volatilize, especially when the vegetable field is short of water. The application of ammonium bicarbonate in vegetable fields, whether as base fertilizer or topdressing fertilizer, should be applied deeply under wet conditions, and the soil should be covered immediately after application.

6. Do not apply too much phosphate fertilizer: if a large amount of phosphate fertilizer is applied in vegetable fields in successive years, the supply of phosphate fertilizer is too much, especially if the amount of phosphate fertilizer per mu is more than 40 kg, it will do great harm, seriously affect the development of vegetables, lead to premature senescence, poor growth, reduced yield and poor quality. Generally speaking, it is appropriate to apply 15 Mu and 20 kg per mu.

7. Green leafy vegetables must not apply non-rotten acquaintance manure: stranger dung, especially in hospitals, stations, docks, restaurants and other public toilets, contains a variety of infectious bacteria and parasite eggs. For example, this kind of manure is directly spilled on green leafy vegetables without retting or treatment, the vegetables are contaminated, and even lead to the transmission of infectious diseases and parasitic diseases. The use of this kind of manure can be applied after harmless treatment such as sealed composting, biogas digester fermentation, drug treatment and so on.

8. Livestock manure should be applied after composting: straw and weeds are mostly used in the feed of pigs and cattle, but there are a lot of weed seeds mixed with straw and weeds, and the weed seeds in livestock manure manure have strong vitality and can still germinate and propagate as the manure is brought into the vegetable field, which does great harm to vegetables. The stable manure should be put out of the circle and compost at high temperature to kill weed seeds, parasite eggs and pathogenic bacteria in livestock manure. In general, natural composting can be applied in about 2 months, if treated with biological starter, compost can be done for 10 days.