CN113402334A

CN113402334A - Composite microbial nitrogen fertilizer and preparation method thereof

Info

Publication number: CN113402334A
Application number: CN202110840768.XA
Authority: CN
Inventors: 蒙世协; 谢家幸; 蒙晓燕; 黄乃佾; 黄和年
Original assignee: Guangxi Bailongteng Biotechnology Co ltd
Current assignee: Guangxi Bailongteng Biotechnology Co ltd
Priority date: 2021-07-25
Filing date: 2021-07-25
Publication date: 2021-09-17

Abstract

The invention discloses a compound microbial nitrogen fertilizer and a preparation method thereof, wherein the compound microbial nitrogen fertilizer comprises the following raw materials: urea, ammonium sulfate, molasses fermented potassium fulvate bottom material, composite biological bacteria, nutrient dry powder, zinc element and boron element. The compound microbial nitrogen fertilizer adopts molasses fermented alcohol residual sediment as a main bottom material, has high organic matter content, small molecules and high activity, can effectively loosen and improve soil, and the added compound microbial bacteria can more quickly propagate and grow on the molasses fermented potassium fulvate bottom material, have better and higher activity, more effectively loosen and activate the soil, promote healthy and robust growth of crop roots, have more developed and robust roots and stronger capability of absorbing water and nutrients; through the contained fulvic acid and amino acid, nitrogen elements, calcium, magnesium, zinc, boron and other nutrient elements are effectively chelated, nitrogen is less prone to being converted and lost, the fertilizer efficiency period of nitrogen is longer, the utilization rate is higher, the nitrogen is more prone to being absorbed and utilized, and the effect is more obvious.

Description

Composite microbial nitrogen fertilizer and preparation method thereof

Technical Field

The invention belongs to the technical field of fertilizers, and particularly relates to a compound microbial nitrogen fertilizer and a preparation method thereof.

Background

With the development of modern agriculture, the use amount of chemical fertilizers is increased year by year, especially the use amount of nitrogen fertilizers, after the traditional nitrogen fertilizers are applied to soil, the part absorbed and utilized by crops only accounts for about 30 percent of the total amount of the applied fertilizers, and the rest is volatilized (NH)₃) Eluviation (NO)₂ ^-And NO₃ ^-) And denitrification whitening loss, which not only wastes fertilizer, increases cost, but also results in NO₂ ^-And NO₃ ^-Contaminated surface water and groundwater and N₂Contamination of the atmosphere with O (products of nitrification and denitrification).

Aiming at the problems that the traditional nitrogen fertilizer in modern agriculture has low utilization rate and short fertilizer effect period, causes pollution to the environment, and is continuously planted all year round, the soil aggregate structure is seriously damaged, the organic matter of the soil is lack, the soil is hardened and acidified, the growth of root systems is influenced, the absorption and the utilization of nutrients and water of crops are influenced, the company and Guangxi agricultural institute resource and environment research institute are jointly developed, potassium fulvate precipitate obtained after molasses ferments alcohol is used as a main base material, and medium trace elements such as compound microorganism bacteria (bacillus subtilis, bacillus licheniformis and bacillus megaterium) and calcium, magnesium, zinc, boron and the like which can effectively loosen and activate the soil are added, so that the soil is effectively improved, the soil fertility is fertilized, the healthy and healthy growth of the root systems of the crops is promoted, the absorption and the utilization of the root systems of the crops to the nutrients, particularly nitrogen are improved, and the nitrogen effect period and the utilization rate are improved.

At present, there are three main techniques for improving the utilization rate and the efficiency of nitrogen:

a biochemical method is characterized in that biochemical inhibitors are added into the fertilizer, and urease inhibitors and nitrification inhibitors are mainly added into the fertilizer. Such as long-acting urea, microbial nitrogen fertilizer and the like;

and the second physical method is a fertilizer obtained by a physical coating method and an integral dispersion method. The physical coating method is to coat one or more layers of permeation diffusion retarding layers on the surface of the soluble granular fertilizer to slow or control the nutrient dissolution rate of the fertilizer, such as sulfur coated urea, polymer coated fertilizer, coated urea and coated fertilizer; the integral dispersion method is that the fertilizer is uniformly dispersed and absorbed in the controlled release material to form a porous network system, the fertilizer nutrient is desorbed along with the controlled release material or is released along with the corrosion or degradation of the controlled release material to the fertilizer nutrient, and the controlled release material can be rubber, asphalt, gel and the like;

the fertilizer is chemically synthesized synergistic fertilizer, and is connected to preformed polymer directly or indirectly through covalent or ionic bond to form one new kind of composition. Generally, there are 3 types: insoluble organic compounds including urea formaldehyde, crotonobiurea, oxalic amide, and the like; water-soluble refractory compounds such as isobutylidene diurea; low solubility inorganic salts such as magnesium ammonium phosphate and the like.

The nitrogen fertilizer adopting the three technologies can improve the absorption and utilization rate of nitrogen within a certain range and to a certain extent, but has influence and damage on soil and environment. The biochemical inhibitor inhibits the transformation of nitrogen form by inhibiting the activity of soil microorganisms, namely urease or nitrobacteria, so as to prevent and control the loss of nitrogen, improve the retention time of nitrogen in soil and prolong the fertilizer efficiency period to a certain extent, but influence and damage the soil microorganisms, destroy the ecological balance of the soil and be not beneficial to improving the soil; the nitrogen fertilizer modified by physical or chemical technology has direct influence on soil and environment, and cannot be used as a nitrogen fertilizer product which can be used for a long time.

Disclosure of Invention

The invention aims to provide a compound microbial nitrogen fertilizer and a preparation method thereof, and aims to solve the problems that nitrogen fertilizers modified by physical or chemical technologies in the prior art directly affect soil and environment and cannot be used as nitrogen fertilizer products for a long time and the like.

In order to solve the technical problems, the invention adopts the following technical scheme:

the composite microbial nitrogen fertilizer comprises the following raw materials in parts by mass: 10-20 parts of urea, 40-55 parts of ammonium sulfate, 20-25 parts of molasses fermented potassium fulvate bottom material, 0.5-1.0 part of composite biological bacteria, 1-3 parts of nutrient dry powder and 0.5-1 part of trace elements of zinc and boron.

Further, the bottom material of the molasses fermented potassium fulvate is the potassium fulvate precipitate remained in the molasses fermented alcohol.

Further, the compound biological bacteria comprise bacillus subtilis, bacillus licheniformis and bacillus megaterium.

Further, the bacillus subtilis is bacillus subtilis of 14 strains.

Further, the 14 strain bacillus subtilis is 0.8-1.5 hundred million/gram.

Further, the bacillus licheniformis is 0.3-0.5 hundred million/g.

Further, the number of the bacillus megaterium is 0.3 to 0.5 hundred million/g.

Further, the nutritional dry powder comprises the following components in percentage by mass: 30.28 percent of magnesium oxide, 17.13 percent of water-soluble magnesium, 16.66 percent of sulfur, 5.31 percent of calcium, 8.58 percent of silicon, 0.36 percent of ferrum, 0.005 percent of boron, 0.0016 percent of copper, 0.013 percent of zinc, 1 to 2.5 percent of phosphorus pentoxide, 3 to 7 percent of potassium oxide and 1 to 2 percent of nitrogen.

Furthermore, the ratio of the trace elements of zinc and boron is 2: 1.

The invention also provides a preparation method of the compound microbial nitrogen fertilizer, which comprises the following steps:

(1) adding urea and ammonium sulfate in parts by mass into a pulverizer to pulverize to obtain a pulverized material;

(2) adding molasses fermented potassium fulvate base material, trace elements zinc and boron into the crushed material prepared in the step (1), and adding into a forced mixer to mix uniformly to prepare a mixture;

(3) putting the mixture prepared in the step (1) into a material distributor for material distribution, and then putting the mixture into a high-strength disc roller granulator for granulation to prepare granules;

(4) adding composite biological bacteria and nutrient dry powder into the particles prepared in the step (3), and then putting the particles into a screening machine to respectively carry out primary screening and secondary screening to obtain screened substances;

(5) and (4) packaging the screened material obtained in the step (4) in an automatic packaging machine, and then obtaining the compound microbial nitrogen fertilizer after the screened material is qualified.

The invention has the following beneficial effects:

1. the composite microbial nitrogen fertilizer disclosed by the invention has the advantages that the microbial strain is more than or equal to 2 hundred million/g (14 strains of bacillus subtilis, bacillus licheniformis and bacillus megatherium), the nitrogen is more than or equal to 20 percent (amide nitrogen and ammonium nitrogen), the organic matter (potassium fulvate) is more than or equal to 15 percent, the polypeptide amino acid is more than or equal to 5 percent, the calcium and magnesium are more than or equal to 2 percent, the total amount of zinc and boron is 1500ppm, the pH value of the product is 6-7, the product is neutral, the soil is conditioned and improved, and the activity of a root system is high;

2. organic matters of the product are provided for potassium fulvate obtained after molasses is fermented with alcohol, and the product has the advantages of small molecules, high activity, loosening and activating soil, stimulating root growth, rooting and seedling lifting, and improving drought and cold resistance of crops;

3. the product microbial bacteria are compound microbial bacteria, are organically combined by 14 strains of bacillus subtilis, bacillus licheniformis and bacillus megaterium, and can better and faster propagate, better and faster loosen and activate soil, improve and condition the soil and promote healthier and more robust growth of root systems on the basis of potassium fulvate organic materials;

4. the product of the invention has about 20 percent of nitrogen, is composed of amide nitrogen and ammonium nitrogen in scientific proportion (amide nitrogen urea provides, urea contains 46.3 percent of nitrogen, ammonium nitrogen is provided by ammonium sulfate, and ammonium sulfate contains 20.5 percent of nitrogen, and the proportion of the amide nitrogen and the ammonium nitrogen is close to 1: 3 according to the feeding proportion of the urea and the ammonium sulfate);

5. the compound microbial nitrogen fertilizer belongs to an organic nitrogen fertilizer, can effectively improve soil, improve the microbial growth environment of the soil, promote root growth, promote nutrient absorption and utilization, make crops grow stronger and healthier and relatively reduce plant diseases and insect pests after long-term use;

6. the composite microbial nitrogen fertilizer adopts molasses fermented alcohol residual sediment as a main base material, has high organic matter content, small molecules and high activity, can effectively loosen and improve soil, can more quickly propagate and grow on the molasses fermented potassium fulvate base material by adding composite microbial bacteria (bacillus subtilis, bacillus licheniformis and bacillus megatherium), has better and higher activity, can more effectively loosen and activate soil, promotes healthy and robust growth of crop root systems, has more developed and robust root systems and stronger water and nutrient absorption capacity, and can effectively chelate (double-chelating technology) nitrogen elements, calcium, magnesium, zinc, boron and other nutrient elements contained in the molasses fermented alcohol residual potassium fulvate sediment in the microbial nitrogen fertilizer production process, so that nitrogen is less prone to be converted and lost, the nitrogen has longer fertilizer effect period, higher utilization rate, easier absorption and utilization and more obvious effect.

Detailed Description

For a better understanding of the present invention, the following examples are given to illustrate, but not to limit the scope of the present invention.

In the following examples, the composite microbial nitrogen fertilizer comprises the following raw materials in parts by mass: 10-20 parts of urea, 40-55 parts of ammonium sulfate, 20-25 parts of molasses fermented potassium fulvate bottom material, 0.5-1.0 part of composite biological bacteria, 1-3 parts of nutrient dry powder, and 0.5-1 part of trace elements of zinc and boron;

the bottom material of the molasses fermented potassium fulvate is the remaining potassium fulvate precipitate of the molasses fermented alcohol;

the compound biological bacteria comprise bacillus subtilis, bacillus licheniformis and bacillus megaterium;

the bacillus subtilis is 14 strains of bacillus subtilis, and the number of the 14 strains of bacillus subtilis is 0.8-1.5 hundred million/g;

the bacillus licheniformis is 0.3-0.5 hundred million/g, and the bacillus megatherium is 0.3-0.5 hundred million/g;

the nutritional dry powder comprises the following components in percentage by mass: 30.28 percent of magnesium oxide, 17.13 percent of water-soluble magnesium, 16.66 percent of sulfur, 5.31 percent of calcium, 8.58 percent of silicon, 0.36 percent of ferrum, 0.005 percent of boron, 0.0016 percent of copper, 0.013 percent of zinc, 1 to 2.5 percent of phosphorus pentoxide, 3 to 7 percent of potassium oxide and 1 to 2 percent of nitrogen;

the dosage ratio of the trace elements zinc and boron is 2: 1;

the preparation method of the compound microbial nitrogen fertilizer comprises the following steps:

The following is a more specific example.

Example 1

The composite microbial nitrogen fertilizer comprises the following raw materials in parts by mass: 11 parts of urea, 42 parts of ammonium sulfate, 20 parts of molasses fermented potassium fulvate base material, 0.5 part of composite biological bacteria, 1 part of nutrient dry powder and 0.5 part of trace elements of zinc and boron;

the compound biological bacteria comprise 0.1 part of bacillus subtilis, 0.2 part of bacillus licheniformis and 0.2 part of bacillus megatherium;

the bacillus subtilis is 14 strains of bacillus subtilis, and the number of the 14 strains of bacillus subtilis is 1.3 hundred million/g;

the number of bacillus licheniformis is 0.4 hundred million/g, and the number of bacillus megatherium is 0.4 hundred million/g;

the nutritional dry powder comprises the following components in percentage by mass: 30.28 percent of magnesium oxide, 17.13 percent of water-soluble magnesium, 16.66 percent of sulfur, 5.31 percent of calcium, 8.58 percent of silicon, 0.36 percent of iron, 0.005 percent of boron, 0.0016 percent of copper, 0.013 percent of zinc, 1.2 percent of phosphorus pentoxide, 3.2 percent of potassium oxide and 1 percent of nitrogen;

the dosage ratio of the trace elements zinc and boron is 2: 1;

Example 2

The composite microbial nitrogen fertilizer comprises the following raw materials in parts by mass: 16 parts of urea, 48 parts of ammonium sulfate, 23 parts of molasses fermented potassium fulvate bottom material, 0.7 part of composite biological bacteria, 2 parts of nutrient dry powder and 0.9 part of trace elements of zinc and boron;

the compound biological bacteria comprise 0.2 part of bacillus subtilis, 0.4 part of bacillus licheniformis and 0.1 part of bacillus megatherium;

the bacillus subtilis is 14 strains of bacillus subtilis, and the number of the 14 strains of bacillus subtilis is 1.2 hundred million/g;

the number of bacillus licheniformis is 0.4 hundred million/g, and the number of bacillus megatherium is 0.5 hundred million/g;

the nutritional dry powder comprises the following components in percentage by mass: 30.28 percent of magnesium oxide, 17.13 percent of water-soluble magnesium, 16.66 percent of sulfur, 5.31 percent of calcium, 8.58 percent of silicon, 0.36 percent of iron, 0.005 percent of boron, 0.0016 percent of copper, 0.013 percent of zinc, 2 percent of phosphorus pentoxide, 5.2 percent of potassium oxide and 1.7 percent of nitrogen;

the dosage ratio of the trace elements zinc and boron is 2: 1;

Example 3

The composite microbial nitrogen fertilizer comprises the following raw materials in parts by mass: 18 parts of urea, 54 parts of ammonium sulfate, 24 parts of molasses fermented potassium fulvate bottom material, 1.0 part of composite biological bacteria, 3 parts of nutrient dry powder and 0.9 part of trace elements of zinc and boron;

the compound biological bacteria comprise 0.5 part of bacillus subtilis, 0.2 part of bacillus licheniformis and 0.3 part of bacillus megatherium;

the dosage ratio of the trace elements zinc and boron is 2: 1;

Test cases:

the first test case is as follows: test for applying composite microbial nitrogen fertilizer to rice

1. Materials and methods

(1) Test site and soil conditions

The test is carried out in the responsibility field of Chilobrachys jingzhao peasant households in Nanmu Zhen Luo Chigzhao city, the area of which is 470m²The previous crops are rice, the soil to be tested is a soil retention yellow mud field, and the fertilizer test is not carried out in recent years.

(2) Test method

The experiment was set up with four treatments, three replicates and a cell area of 22m²Random permutation, the process content is as follows:

treatment 1: 30 kg/mu of the compound microbial nitrogen fertilizer, 25 kg/mu of calcium magnesium phosphate fertilizer and 10 kg/mu of potassium chloride in the embodiment 1; the application method comprises the following steps: wherein 50% of the compound microbial nitrogen fertilizer of the example 1, 100% of the calcium magnesium phosphate fertilizer, 50% of potassium chloride and 50% of the compound microbial nitrogen fertilizer and potassium chloride of the example 1 are applied to the base fertilizer.

And (3) treatment 2: 18.2 kg/mu of urea, 25 kg/mu of calcium magnesium phosphate fertilizer and 10 kg/mu of potassium chloride, and the application method (the application ratio of the urea) is the same as that of the treatment 1.

And (3) treatment: 25 kg/mu of calcium magnesium phosphate fertilizer and 10 kg/mu of potassium chloride, and the application method is the same as that of the treatment 1.

And (4) treatment: blank control, no fertilizer was applied.

(3) Test conditions: sowing in 7-month and 10-day 2020, land preparation in sub-districts and field insertion in 8-month and 6-day sub-districts, and planting specifications are as follows: throwing seedlings for 1.8 ten thousand basic seedlings per mu. Harvesting in 11 months and 15 days, and performing yield calculation in a single yield mode in the whole cell. Other management measures in the test are consistent.

2. Test results and analysis

(1) Effect of different treatments on Rice growth periods

TABLE 1 leaf color record table of rice growth period by different treatments

As can be seen from table 1, the leaf color was dark green from the tillering stage to the heading stage in treatments 1 and 2, indicating that the nitrogen supply was sufficient throughout the growth process, while the leaf color was light green from the tillering stage to the heading stage in treatments 3 and 4 due to insufficient nitrogen supply.

TABLE 2 description of growth period of rice by different treatments (day/month)

As can be seen from Table 2, the reversion period and the tillering period of the treatments 1 and 2 are 2-3 days earlier than the treatments 3 and 4, which indicates that the rice crops can grow earlier and tillering is promoted by applying nitrogen fertilizer.

TABLE 3 plant agronomic trait survey table

As can be seen from Table 3, the plant height, the number of effective ears per mu, the total number of grains and the number of filled grains of treatments 1 and 2 were higher than those of treatments 3 and 4. Wherein the effective spike number per mu of the treatment 1 and the treatment 2 is 1.50, 2.77, 1.44 and 2.71 ten thousand spikes higher than the treatment 3 and the treatment 4 respectively.

TABLE 4 statistical table of the acceptance of different treatments (unit: kg/666.7 m)²)

TABLE 5 ANOVA TABLE

Cause of change	Degree of freedom	Sum of squares	Mean square	F value	F0.05	F0.01
							Treatment room	3	47194.0	15731.3	50.92**	4.07	7.59
Repeating room	2	93.4	46.7	0.15
							Error of the measurement	6	1853.6	308.9
Total variation	11	49141.0

The difference among the F value test treatments reaches a very significant level (50.92> F0.01)

Multiple comparison results

TABLE 6 comparison of new repolarization differences

P	2	3	4
				SSR0.05	3.46	3.58	3.64
SSR0.01	5.24	5.51	5.65
				LSR0.05	35.11	36.33	36.94
LSR0.01	53.17	55.91	57.33

TABLE 7 TABLE of results of significance testing of different treatment differences

As can be seen from table 7, the differences between treatments 1 and 2 and treatments 3 and 4 reach very significant levels; the difference between the treatment 3 and the treatment 4 reaches an extremely significant level; the difference between treatment 1 and treatment 2 did not reach a significant level.

TABLE 8 comparison of the yields and values of the different treatments (kg/666.7 m)²Yuan/666.7 m²)

Processing comparisons	Increase production	Increase in yield	Cost of new fertilizer	Pure yield increase
					Treatment 1 vs. treatment 2	8.1	16.2	-30.17	46.37
Treatment 1 vs. treatment 3	70.7	141.4	45.00	96.40
					Treatment 1 vs. treatment 4	156.6	313.2	103.75	209.45
Treatment 2 vs. treatment 3	62.6	125.2	75.17	50.03
					Treatment 2 vs. treatment 4	148.5	297.0	133.92	163.08
Treatment 3 vs treatment 4	85.9	171.8	58.75	113.05

Note: according to the market price, 2.00 yuan/kg of rice, 1.5 yuan/kg of compound microbial nitrogen fertilizer, 1.9 yuan/kg of urea, 0.75 yuan/kg of 14% calcium magnesium phosphate fertilizer, 4.00 yuan/kg of potassium chloride and 20.0 yuan/time of fertilization.

And (4) conclusion: 30.0kg of compound microbial nitrogen fertilizer is applied to each mu of rice. (1) On the basis of the same phosphorus and potassium nutrients, the compound microbial nitrogen fertilizer is applied to each mu, the yield is increased by 70.7kg, and the yield is increased by 17.5%; pure income 96.4; the single factor difference Beijing biometric test reaches a very significant level. (2) Compared with urea with the same nutrient content as pure N, the yield is increased by 8.1kg and only 1.7%; pure income is 46.37 yuan, and single factor difference does not reach a significant level through a biometrical test.

Test case two: test of fertilizer efficiency of composite microbial nitrogen fertilizer on corn

1. Materials and methods

(1) The test crop is corn, and the test fertilizer is the compound microbial nitrogen fertilizer of example 2

(2) Test method

The test was carried out by setting three treatments, randomly arranging in blocks, repeating three times, and making the area of the cell 40m²。

Treatment 1: according to the recommended fertilizer application program of the local soil testing formula, 33.0kg of urea (with the market retail price of 1900 yuan/ton), 15.7kg of calcium superphosphate (with the market retail price of 650 yuan/ton) and 4.2kg of potassium chloride (with the market retail price of 3000 yuan/ton) are applied per mu;

and (3) treatment 2: 68.0kg (1500 yuan/ton) of the compound microbial nitrogen fertilizer of the embodiment 2 is applied per mu

And (3) treatment: local farmers are used to apply fertilizer, and urea is applied at 33.0kg per mu.

The test is carried out according to the requirements of the scheme, and other management measures are the same as those of the common field.

2. Results and analysis

TABLE 9 statistical table for field investigation and seed test

(Note: data in Table are the average of three treatment replicates)

From table 9, it can be seen that: the average grain number of the rows of the treatment 2 is increased by 0.23 and 0.43 compared with the rows of the treatment 1 and the treatment 3, the average grain number of the rows is increased by 0.14 and 0.17, and the thousand grain weight is increased by 3.70 and 8.45 g. The application of the composite microbial nitrogen fertilizer can increase the ear rows, the number of the rows and the thousand grain weight of the corn. Meanwhile, the plant height and the ear position of the corn are also increased.

TABLE 10 statistical Table of yield results

TABLE 11 ANOVA TABLE

Cause of change	SS	DF	MS	F	F0.05	F0.01
							Treatment room	4.34	2	2.17	37.02**	6.94	18.00
Repeating room	0.13	2	0.06	1.09
							Error of the measurement	0.23	4	0.06
Total variation	4.70	8

TABLE 12 multiple comparison Table

3. Small knot

The compound microbial nitrogen fertilizer improves the yield factor of the corn, increases the ear row number, the row grain number and the thousand grain weight of the corn compared with the formula fertilizer, increases the yield by 14.0kg per mu on average, increases the yield by 2.3 percent, has obvious yield difference, and increases the yield by 28.3kg per mu on average compared with the habit fertilizer application of farmers. The amplification is 4.8%, and the yield difference reaches an extremely obvious level. In the three treatments, under the condition that the costs of labor and nitrogen fertilizers are consistent, the input cost of the fertilizer recommended for fertilization is 77 yuan/mu at most, and the input cost of the microbial nitrogen fertilizer and the input cost of the fertilizer used for habitual fertilization are 54 yuan/mu consistently. The yield of the compound microbial nitrogen fertilizer is the highest.

Test case three: summary of composite microbial nitrogen fertilizer test for potatoes

1. Materials and methods

(1) Fertilizer to be tested: according to the measured value of the fertilizer application soil of the soil measuring formula and the characteristics of the fertilizer requirement of the potatoes, the fertilizer is the compound microbial nitrogen fertilizer of the embodiment 3; control fertilizer: urea, containing 46% of N.

(2) Design of experiments

The test was performed on locally watered potatoes. The method is characterized by comprising the steps of selecting Guofu root in Hovenia village, Altai village, which has high soil fertility and is suitable for potato growth, and carrying out the Guofu root contract in a land area of 10 mu, wherein 3 mu of the compound microbial nitrogen fertilizer (30 kg applied in mu) in example 3, 3 mu of the same amount of conventional fertilizer (13 kg applied in urea mu) and 3 mu of equivalent conventional fertilizer (11.5 kg applied in urea mu) are set for comparison with 1 mu (no topdressing), and the variety is cultivated by detoxification gram of New No. 1 first-grade plantation and low ridging.

(3) Fertilizer application method

The compound microbial nitrogen fertilizer and urea are used as top dressing fertilizer to be applied at one time, a top dressing gun is used for manually and intensively applying the top dressing fertilizer between two potatoes in a sowing row within 7 months and 25 days, watering is carried out within 27 days, and the fertilizing depth is 12 cm.

TABLE 13 microbial nitrogen fertilizer test production table

And (4) preliminary conclusion: the yield of the potatoes is increased by 10.9 percent by using the compound microbial nitrogen fertilizer, the yield increasing effect is slightly higher than 7.4 percent of urea with equal content and 8.0 percent of equivalent urea, and the compound microbial nitrogen fertilizer is suitable for being popularized and used in potato areas.

The above description should not be taken as limiting the invention to the embodiments, but rather, as will be apparent to those skilled in the art to which the invention pertains, numerous simplifications or substitutions may be made without departing from the spirit of the invention, which shall be deemed to fall within the scope of the invention as defined by the claims appended hereto.

Claims

1. The compound microbial nitrogen fertilizer is characterized by comprising the following raw materials in parts by mass: 10-20 parts of urea, 40-55 parts of ammonium sulfate, 20-25 parts of molasses fermented potassium fulvate bottom material, 0.5-1.0 part of composite biological bacteria, 1-3 parts of nutrient dry powder and 0.5-1 part of trace elements of zinc and boron.

2. The compound microbial nitrogen fertilizer as claimed in claim 1, wherein the molasses fermented potassium fulvate base material is potassium fulvate precipitate remaining from molasses fermented alcohol.

3. The compound microbial nitrogen fertilizer of claim 1, wherein the compound biological bacteria comprise bacillus subtilis, bacillus licheniformis and bacillus megaterium.

4. The compound microbial nitrogen fertilizer of claim 3, wherein the Bacillus subtilis is 14 strains of Bacillus subtilis.

5. The compound microbial nitrogen fertilizer of claim 4, wherein the 14 strain bacillus subtilis is 0.8-1.5 million/g.

6. The compound microbial nitrogen fertilizer of claim 3, wherein the bacillus licheniformis is 0.3-0.5 hundred million/g.

7. The compound microbial nitrogen fertilizer of claim 3, wherein the bacillus megaterium is 0.3-0.5 hundred million/g.

8. The compound microbial nitrogen fertilizer of claim 1, wherein the nutritional dry powder comprises, in mass fraction: 30.28 percent of magnesium oxide, 17.13 percent of water-soluble magnesium, 16.66 percent of sulfur, 5.31 percent of calcium, 8.58 percent of silicon, 0.36 percent of ferrum, 0.005 percent of boron, 0.0016 percent of copper, 0.013 percent of zinc, 1 to 2.5 percent of phosphorus pentoxide, 3 to 7 percent of potassium oxide and 1 to 2 percent of nitrogen.

9. The compound microbial nitrogen fertilizer of claim 1, wherein the ratio of the trace elements zinc and boron is 2: 1.

10. A method for preparing a compound microbial nitrogen fertilizer according to any one of claims 1-9, comprising the following steps: