How to choose and buy chemical fertilizer? Common sense of Chemical Fertilizer selection and Scientific Application

Chemical fertilizer refers to the fertilizer made by chemical method or mining ore, which is also called inorganic fertilizer, including nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, micro-fertilizer, compound fertilizer, etc. So, how should fertilizer be purchased? Below, Xiaobian will specifically talk about chemical fertilizer purchase and scientific application of small common sense.

How to choose a good compound fertilizer

1, to choose regular manufacturers of products

Because the production equipment and production technology of regular manufacturers are very advanced, the products produced are uniform in particles, balanced in nutrients and stable in quality. And the product formula is developed by experts according to the characteristics of soil nutrients and crops through long-term experiments. The formula is reasonable, targeted, full of nutrients, sufficient in content, and safe to use.

2, according to the local soil conditions, reasonable selection of compound fertilizer

Fertilizers come in acidic and alkaline forms, as do soils. Such as saline-alkali land, it is necessary to choose an acidic compound fertilizer with ammonium nitrate as the nitrogen source, which can not only supply the nutrients needed by crops, but also reduce the alkalinity of the soil. At the same time, it also avoids the adverse effects of "chlorine damage" and "salt damage" on crops.

3, the choice of compound fertilizer must calculate the input and output ratio

When selecting compound fertilizer, we must calculate the ratio of input and output, and choose compound fertilizer with reasonable price. Because the key problem of increasing agricultural production and income lies in the reduction of agricultural cost, it is very important to choose a fertilizer with good quality and reasonable price, otherwise it is not worth the loss.

Second, what problems should be paid attention to in the application of compound fertilizer

1. Compound fertilizer is generally used as base fertilizer or seed fertilizer.

When making base fertilizer, it should be applied before sowing and soil preparation, generally applied to 10-20 cm below the ploughing layer; when making seed fertilizer, it must pay attention to seed fertilizer isolation, generally applied to 5-6 cm below the ploughing layer.

2. Fertilization should be reasonable

Applying compound fertilizer is not the more the better. Blindly applying compound fertilizer not only increases the cost, but also easily causes problems such as burning seeds and burning seedlings, which affect the rational absorption of nutrients by crops. When using, we must calculate the reasonable fertilizer amount according to the product instructions and combined with the past fertilizer application amount in this area.

3. Applying compound fertilizer is not once and for all

Because although compound fertilizer can mostly meet the needs of crop growth and development for various nutrients, but in the rapid growth period of crops such as heading, filling period and other periods, nitrogen demand is very large, must be appropriate topdressing nitrogen, otherwise it will have a great impact on yield, even if the nitrogen raw material of compound fertilizer uses long-acting urea.

Third, how to prevent mistakes in fertilizer application

Some farmers in the fertilizer to crops, due to improper use of fertilizer, technology, resulting in fertilizer utilization rate is not high, fertilizer costs increase, and even cause crops to suffer and lead to reduced yield.

Mistake one: calcium magnesium phosphate fertilizer for topdressing. Calcium magnesium phosphate is not easy to dissolve in water, fertilizer efficiency is slow, especially in the middle of crop growth after topdressing, its utilization rate is low, the effect is poor. The correct application method is: calcium magnesium phosphate fertilizer can only be used as base fertilizer and organic fertilizer mixed application, seed dressing fertilizer efficiency is also good.

Mistake 2: urea, ammonium bicarbonate and other nitrogen fertilizer shallow application, spread or application concentration is too high. Urea is an amide nitrogen fertilizer with high nitrogen content. After being applied to soil, most of it can be absorbed and utilized by crops only after it is converted into ammonium nitrogen by urease secreted by microorganisms, except for a small amount which is directly absorbed and utilized by plants. The nature of ammonium bicarbonate is unstable, the utilization rate of shallow application on the ground is low, and at the same time, the amount of topdressing nitrogen fertilizer is large, and the concentration is too high. The ammonia volatilized will fumigate the stems and leaves of crops and cause fertilizer damage. The correct application method is: nitrogen fertilizer should be applied in furrows or holes, 5-10 cm deep, and covered with soil. For foliar fertilizer spraying should control the concentration, wheat, rice, cotton, corn, etc. to 0.8%-1% is appropriate; vegetable spraying concentration should be low.

Mistake 3: direct seed dressing with superphosphoric acid. Calcium superphosphate contains 3.5%-5% free acid, which is very corrosive. Direct seed dressing will reduce the germination rate and emergence rate of seeds. The correct application method is: topdressing should be furrowing deep application. Seed fertilizer should be applied 5-6 cm below or beside the seed, and soil should be used to separate the fertilizer from the seed.

Mistake 4: zinc fertilizer and phosphate fertilizer mixed application. Due to the serious "antagonism" between zinc and phosphorus, such as the mixed application of zinc sulfate and calcium superphosphate, the fertilizer efficiency of zinc sulfate can be inhibited to a large extent, so that its effectiveness decreases. The correct application method is: zinc fertilizer and phosphorus fertilizer should be applied separately, phosphorus fertilizer as base fertilizer, zinc fertilizer as seedling fertilizer, or zinc fertilizer as base fertilizer, phosphorus fertilizer as seedling fertilizer, which can improve the efficiency of phosphorus and zinc fertilizer.

Mistake 5: cold water dissolves borax spray. Because borax dissolves in cold water, it will soon appear "recrystallization", resulting in borax solution precipitation and loss of fertilizer effect. Correct application method: first put boron fertilizer into a thermos bottle, add boiling water to dissolve, cover the bottle tightly and bring it to the field, and then cool the water to the required concentration, the effect will be greatly improved.

Four, the application of urea six mistakes

Urea contains 46% nitrogen, which is a high-quality chemical nitrogen fertilizer used more in rural areas. According to the author's understanding, some farmers are not too clear about the nature of urea, and there are still the following six misunderstandings in use.

Mistake 1: urea mixed with ammonium bicarbonate. Because urea is applied to the soil, it must be converted into ammonia before it can be absorbed by crops, and its conversion rate is much slower under alkaline conditions than under acidic conditions. Ammonium bicarbonate is alkaline when applied to soil, pH value is 8.2-8.4. Mixed application of ammonium bicarbonate and urea in farmland will greatly slow down the conversion rate of urea into ammonia, which is easy to cause urea loss and volatilization loss. Therefore, urea and ammonium bicarbonate should not be mixed or applied simultaneously.

Mistake 2: surface spreading. Urea is scattered on the ground, and it takes 3-5 days to be absorbed by crops at normal temperature. Most of the nitrogen is volatilized in the process of urea conversion into ammonium, and the utilization rate is only about 30%. If it is scattered in alkaline soil, the loss of nitrogen is faster and more. Therefore, nitrogen cannot be applied to the ground.

Mistake 3: urea as seed fertilizer. In the process of urea production, a small amount of biuret is often produced. Biuret content of more than 2%, will be toxic to seeds and seedlings. When urea enters seeds and seedlings, it will denature proteins and affect seed germination and seedling growth.

Mistake 4: Irrigation immediately after urea application. Urea is an amide nitrogen fertilizer, which must be converted into ammonium nitrogen after application before it can be absorbed and utilized by crops. The transformation process varies with soil quality, moisture and temperature, and generally takes 2-10 days to complete. If urea is applied immediately after irrigation or before heavy rain in dry land, urea will dissolve in water and be lost.

Mistake 5: urea mixed with alkaline fertilizer. Urea must be converted into ammonium nitrogen after application before it can be absorbed and utilized by crops in large quantities. Ammonium nitrogen in alkaline conditions, most of the nitrogen will become ammonia volatilized, so urea can not be mixed with lime, plant ash, calcium magnesium phosphate fertilizer and other alkaline fertilizers or used at the same time.

Myth 6: urea is applied to celery. Celery throughout the growth period to apply a large number of nitrogen fertilizer, but not urea. Because of topdressing urea, celery fiber increased thickening, plant aging, slow growth, and eating bitter, poor quality. Celery suitable for ammonium bicarbonate, ammonia and organic fertilizer, conducive to improve quality.

V. Balanced fertilization series knowledge

1. What is balanced fertilization?

Balanced fertilization means that all plants of crops can absorb all kinds of nutrients needed for their healthy growth reasonably according to a certain proportion and quantity. It also means that the nutrients obtained by crops from the soil are fertilized, and the nutrients returned to the soil in the form of air and water are balanced, so that crops yield high and the soil is not depleted.

2. How to balance fertilization

The purpose of compound fertilizer production and use is to meet the requirements of agricultural scientific fertilization and economic fertilization, and to achieve balanced fertilization. Because the use of compound fertilizer can save the cost of storage, transportation and application, achieve reasonable fertilizer formulation, and ensure the yield increase effect, especially the special compound fertilizer for local soil nutrients and crop varieties, the effect is better. Therefore, selecting suitable special compound fertilizer is the key to balanced fertilization and an important measure for developing high yield, high quality and efficient agriculture.

3. What effect can balanced fertilization bring

Balanced fertilization can reduce the cost of fertilization due to the reasonable proportion and quantity of various nutrients; balanced nutrient absorption can make plants robust, strengthen the ability to resist diseases, insect pests and drought, and naturally yield and harvest crops.

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