Interaction between different fertilizers

There is a "mutual growth" relationship between fertilizers, and there is also a "mutual restraint" contradiction. For example, if more phosphorus fertilizer is applied, the excess available phosphorus will combine with the available zinc in the soil to form insoluble zinc phosphate precipitation, which will cause the lack of available zinc in the soil. Not only that, the excess available phosphorus will also inhibit the crops from absorbing nitrogen, causing nitrogen deficiency.

Another example is to apply more potassium fertilizers. Excess potassium will reduce the absorption of nitrogen, magnesium, calcium, boron and zinc by crops, causing a lack of these nutrients in crops.

Even organic fertilizers should not be applied too much. If too much is applied, the microorganisms and crops in the soil will have a contradiction of "competing for nitrogen" and "taking nitrogen", which will cause a temporary nitrogen deficiency in the soil for a period of time, and the excess organic matter will form complexes or chelates with zinc, which will reduce the amount of zinc effectiveness.

In order to prevent "comparison" between fertilizers, the following methods can be adopted:

?1. Try to achieve balanced fertilization

Partial application or excessive application of simple fertilizers to crops not only wastes fertilizers and increases production costs, but also easily leads to the lack of some other nutrient elements. When fertilizing, according to the different fertilizer structure of the crops and the fertilizer supply capacity of the soil, it is necessary to achieve the balance of the income and the balance of many nutrients.

2.Try to achieve balanced fertilization

In addition, according to the proportional relationship between the needs of different crops for various nutrient elements, it is necessary to increase and increase at the same time, and to decrease and decrease at the same time. Compared with simple fertilizers, the ratio of nutrient elements in compound fertilizers or compound fertilizers is more appropriate and coordinated. Therefore, compound fertilizers should be used as the main fertilizer, supplemented by simple fertilizers. For example, for crops that require a large amount of potassium, such as vegetables that are harvested from tubers and roots, they can be appropriately increased on the basis of applying sulfur-based compound fertilizers. Potassium sulfate elemental fertilizer is used as a supplement.

3. Stagger the application period or application site

If zinc fertilizer and phosphorus fertilizer are applied together, antagonism will inevitably occur. Therefore, phosphorus fertilizer should be used as base fertilizer or base fertilizer, and zinc fertilizer should be used as top dressing. Fertilizers with large amounts of elements such as nitrogen, phosphorus, and potassium should be based on rhizosphere topdressing, and micro-fertilizers should be sprayed on leaves.

4.Reduce the scope of contact

Nitrogen and potassium fertilizers can be applied by spreading; phosphate fertilizers can be applied by concentrated fertilization; micro-fertilizers can be seed-dressed, soaked, dipped in roots, etc., so that trace elements are limited to the small range of roots, and try not to mix with large amounts of fertilizers. Elemental contact.

Fertilizers contain a variety of elements. Different crops, different soils, and different periods require different elements and dosages. But what is the relationship between these elements? Which elements will be antagonistic??

Nitrogen: It is more difficult to absorb nitrate nitrogen than ammonia nitrogen; excessive application of potassium and phosphorus will affect the absorption of nitrogen; boron deficiency is not conducive to the absorption of nitrogen.

Phosphorus: Increasing zinc can reduce the absorption of phosphorus; more nitrogen is not conducive to the absorption of phosphorus; iron also has an antagonistic effect on the absorption of phosphorus; adding lime can make phosphorus unavailable; magnesium can help the absorption of phosphorus.

Potassium: Increase boron to help the absorption of potassium, zinc can reduce the absorption of potassium; more nitrogen is not conducive to the absorption of potassium; calcium and magnesium have an antagonistic effect on the absorption of potassium.

Calcium: Potassium affects the absorption of calcium and reduces the level of calcium nutrition; magnesium affects the transportation of calcium, and magnesium and boron have an antagonistic effect on calcium; ammonium salts can reduce the absorption of calcium and reduce the transfer of calcium to the fruit; It can also reduce the absorption of calcium; increasing the aluminum, manganese and nitrogen in the soil will also reduce the absorption of calcium.

Magnesium: Potassium affects the absorption of magnesium, a large amount of sodium and phosphorus is not conducive to the absorption of magnesium, and excessive nitrogen can cause magnesium deficiency. Magnesium has an antagonistic effect on calcium, potassium, ammonium, and hydrogen, and the addition of sulfates can cause magnesium deficiency. Magnesium can eliminate the toxicity of calcium. Magnesium deficiency can easily induce zinc and manganese deficiency. Magnesium and zinc help each other.

Iron: Boron affects the absorption of iron and reduces the content of iron in plants. Nitrate nitrogen affects the absorption of iron. Vanadium and iron have an antagonistic effect. There are many elements that cause iron deficiency. Their arrangement order is Ni>Cu>Co> Gr>Zn>Mo>Mn. Potassium deficiency can cause iron deficiency; a large amount of nitrogen, phosphorus and calcium can cause iron deficiency.

Boron: oxides of iron and aluminum can cause boron deficiency; hydroxides of aluminum, magnesium, calcium, potassium, and sodium can cause boron deficiency; long-term lack of nitrogen, phosphorus, potassium, and iron can cause boron deficiency.

Increasing potassium can aggravate the lack of boron, and potassium deficiency will lead to a small amount of boron poisoning; increasing the amount of nitrogen will increase the amount of boron required, which will lead to boron deficiency. Manganese is unfavorable to the absorption of boron, and plants need an appropriate ratio of Ca/B and K/B (for example, the Ca/B of grapes is 1234 mg equivalent, and the K/B is 1142 mg equivalent). and an appropriate Ca/Mg ratio.

Boron has a controlling effect on the Ca/Mg and Ca/K ratios.

Several elements that can form complexes, such as strontium, aluminum and germanium, can temporarily improve the effect of boron deficiency.

Manganese: Calcium, zinc, and iron hinder the absorption of manganese, and the hydroxide of iron can make manganese appear in a precipitated state. Manganese is immobilized by applying physiologically alkaline fertilizers. Vanadium can slow down the poisoning of manganese.

Sulfur and chlorine can increase the released and available manganese, which is beneficial to the absorption of manganese, while copper is not conducive to the absorption of manganese.

Molybdenum: Nitrate nitrogen is conducive to the absorption of molybdenum, ammonia nitrogen is not conducive to the absorption of molybdenum; sulfate is not conducive to the absorption of molybdenum. A large amount of calcium, aluminum, lead, iron, copper, and manganese all hinder the absorption of molybdenum. In the state of phosphorus deficiency and sulfur deficiency, there must be molybdenum deficiency. Increasing phosphorus is beneficial to the absorption of molybdenum, but increasing sulfur is not good; when there is more phosphorus, more molybdenum is needed. Therefore, too much phosphorus sometimes leads to the lack of molybdenum.

Zinc: Zinc forms hydroxides, carbonates and phosphates into an unavailable state. Plants require an appropriate p/Zn ratio (generally 100~120, zinc deficiency if greater than 250).

Excessive phosphorus will lead to zinc deficiency. When there is more nitrogen, more zinc is needed, and sometimes it will lead to zinc deficiency. Nitrate nitrogen is conducive to the absorption of zinc, while ammonia nitrogen is not conducive to the absorption of zinc. Increased potassium and calcium are not conducive to the absorption of zinc.

Manganese, copper, and molybdenum are not good for zinc absorption. There is a mutual absorption effect between magnesium and zinc. Zinc deficiency results in less potassium in the root system. Clays with low Si/Mg ratio in the soil will lack Zn, and Zn antagonizes the absorption of Fe.

Copper: Applying physiologically acidic nitrogen or potassium fertilizers can increase the activity of copper and facilitate absorption. The phosphates, carbonates and hydroxides that produce copper hinder the absorption, so the soil rich in Co2, carbonic acid and calcium is not conducive to the absorption of copper. Too much phosphorus can lead to copper. The H2S produced in the soil anaerobic state also hinders the absorption of copper. Copper is also antagonistic to aluminum, iron, zinc, and manganese. A lot of nitrogen is also not conducive to the absorption of copper.

Poor physical and chemical properties of soil: The physical and chemical properties mentioned here mainly refer to factors related to nutrient absorption. The normal and vigorous growth of the aboveground part depends on the good development of the root system. The deeper and wider the distribution of the root system, the greater the amount of nutrients absorbed, and the more types of nutrients that may be absorbed.

The soil is stiff and firm, and there are hard disks at the bottom, bleached layers, and high groundwater levels, which will limit the extension of the root system, reduce the absorption of nutrients by crops, and aggravate or cause nutrient deficiency.

High groundwater levels, such as some lowlands, often cause potassium deficiency in crops during the rainy season when the groundwater level rises, and in calcareous soils, high groundwater levels also increase bicarbonate ions (HC03-) in the soil solution and affect iron production. Effectiveness, thus triggering or exacerbating iron deficiency, etc. Unreasonable land leveling makes the soil poor and nutrient-poor subsoil rises and often becomes the cause of nutrient deficiency.