Synergistic nitrogen fertilizer for ratooning rice and preparation method thereof

Abstract

The invention relates to the technical field of nitrogen fertilizers, and particularly discloses a synergistic nitrogen fertilizer for ratooning rice, which is prepared from the following raw materials in parts by mass: 100 to 120 parts of urea, 50 to 70 parts of ammonium chloride, 0.5 to 1.5 parts of bacillus subtilis fungicide, 1 to 3 parts of chitosan, 1 to 3 parts of lignin, 1 to 5 parts of urea peroxide, 1 to 3 parts of cellulose acetate, 1 to 3 parts of polyvinyl alcohol, 1 to 2 parts of fulvic acid and 10 to 12 parts of silicon fertilizers. The preparation method comprises the following steps: preparing the following components in parts by weight: 1-2 parts of a nitrification inhibitor, 0.1-0.4 part of berberine, 0.05-0.15 part of nuciferine and 5-15 parts of a chitosan acetic acid solution; the chitosan acetic acid solution is obtained by adding chitosan into an acetic acid solution with the mass fraction of 0.5-1.2% and mixing, and the mass ratio of the chitosan to the acetic acid solution is (1-3): (10-20). The invention also discloses a preparation method of the synergistic nitrogen fertilizer for ratooning rice.

Description

Technical Field

[0001] The invention relates to the technical field of nitrogen fertilizers, and in particular to a synergistic nitrogen fertilizer for regenerated rice and a preparation method thereof. Background Art

[0002] Ratoon rice is a rice planting model that means planting one crop and harvesting two times. Its characteristic is that after one crop of rice matures, only about the upper 2 / 3 of the rice plant is cut off to collect the rice ears, leaving the lower 1 / 3 of the plant and the root system, fertilizing and nurturing it to grow another crop of rice.

[0003] When the first season of rice matures, there will be some axillary buds. After the first season is harvested, they are retained. Based on the original root system, these axillary buds grow again and produce headings. About 2 months later, they mature again and can be harvested. Usually, the grains of rice in the second season are smaller than those in the first season, but the number of rice ears is more than that in the first season (generally, more than 2 ears will grow in the place where the original rice ear is cut), so the yield is not small. The total yield of the two seasons is usually 50% higher than that of the first season (data in Youxi County, Fujian Province in recent years show that nearly 100,000 mu of regenerated rice is planted each year, with an average yield of 600 kg per mu in the first season and 300 kg per mu in the regeneration season), which is of great significance to increasing grain production.

[0004] At present, nitrogen fertilizer is one of the important fertilizers that affects the growth and development of regenerated rice and is one of the important factors that determine the yield. Since the irrational application of fertilizers will lead to low fertilizer utilization, a large amount of nutrients will be lost into the water body, destroying the ecological balance. How to improve fertilizer efficiency and reduce fertilizer loss and improve the soil environment has become a major issue for the sustainable development of agriculture in my country.

[0005] Nitrogen fertilizer enhancers refer to a class of substances that can affect the soil biochemical environment, regulate the activity of some soil enzymes, and affect the response of soil microorganisms to nitrogen fertilizers after entering the soil, thereby reducing nitrogen losses. Traditional nitrogen fertilizer enhancers are not very suitable for rice cultivation, which requires a large amount of water and needs to be urgently addressed. Summary of the invention

[0006] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a synergistic nitrogen fertilizer for regenerated rice and a preparation method thereof.

[0007] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include, by mass, 100-120 parts of urea, 50-70 parts of ammonium chloride, 0.5-1.5 parts of bacillus subtilis agent, 1-3 parts of chitosan, 1-3 parts of lignin, 1-5 parts of urea peroxide, 1-3 parts of cellulose acetate, 1-3 parts of polyvinyl alcohol, 1-2 parts of fulvic acid, 10-12 parts of silicon fertilizer, 1-2 parts of nitrification inhibitor, 0.1-0.4 parts of berberine, 0.05-0.15 parts of nuciferine, and 5-15 parts of chitosan acetic acid solution; the chitosan acetic acid solution is obtained by adding chitosan to an acetic acid solution with a mass fraction of 0.5-1.2% and mixing, and the mass ratio of chitosan to the acetic acid solution is 1-3:10-20.

[0008] Preferably, the silicon fertilizer is natural clinoptilolite.

[0009] Preferably, the mass ratio of berberine to nuciferine is 10-15:4-6.

[0010] Preferably, the nitrification inhibitor is 3,4-dimethylpyrazole phosphate.

[0011] Preferably, the number of viable bacteria in the Bacillus subtilis inoculant is 1-3×10 7 cfu / g.

[0012] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0013] S1, adding chitosan, lignin and urea peroxide to acetic acid solution, stirring at 120-150° C. for 1-3 min, and cooling to room temperature to obtain preform b;

[0014] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, adjusting the temperature to 50-60°C, spraying the prefabricated material b therein, continuing to stir for 5-10 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0015] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, silicon fertilizer, nitrification inhibitor, berberine and nuciferine uniformly, and granulating to obtain a blank;

[0016] S4. Dry the blank, cool it, add it into the drum of the coating machine, adjust the temperature to 50-60°C, spray the chitosan acetic acid solution into it, continue to rotate for 5-10 minutes, discharge it, and dry it in vacuum.

[0017] Preferably, in S1, the mass fraction of the acetic acid solution is 0.5-1.2%.

[0018] Preferably, in S3, a rotary drum steam granulator is used for granulation, and the steam pressure is 100-115 kPa.

[0019] Beneficial effects:

[0020] The present invention can significantly promote nitrogen accumulation and rice growth for regenerated rice, especially in the early stage of regenerated rice. Especially in the regeneration season, the rice not only has a higher plant height and leaf SPAD value, but also can increase the number of effective panicles and the number of grains per panicle in the first season and the regeneration season of the regenerated rice, thereby effectively increasing the rice yield.

[0021] The present invention adopts berberine and nuciferine to chelate with the central ion of urease, effectively inhibiting its catalytic effect. At the same time, the amino group contained in the invention has a molecular structure similar to that of urea, which can produce competitive inhibition on the hydrolysis of urea, promote the absorption of nitrogen nutrients by crops, and indirectly improve the utilization rate of nitrogen fertilizer.

[0022] Urea is very soluble in water. The present invention first performs inner coating on urea to effectively control the sustained-release effect of urea. Then chitosan acetic acid solution is used for coating, and the chitosan acetic acid solution is cross-linked with the internal cellulose acetate during the coating process. Not only does the particle have excellent hydrophilic and water-retaining properties, ensuring the sustained-release of internal substances, but the internal urea fertilizer effect period can also be adjusted, greatly improving the fertilizer effect period and utilization rate of nitrogen fertilizer.

[0023] The invention can improve the utilization efficiency of nitrogen fertilizer in rice planting, inhibit the decomposition of nitrogen fertilizers such as urea in the soil, effectively reduce the loss of nitrogen fertilizer in the soil, and has good biocompatibility. At the same time, it has good mechanical strength to maintain the gel form, which can increase the viscosity of nitrogen fertilizer, prolong the residence time of nitrogen fertilizer in the rice field, and avoid being washed away by water, thereby improving the use effect of the synergist.

[0024] The invention can significantly reduce nitrogen loss, better maintain soil fertility, reduce environmental pollution caused by soil nitrogen loss, and improve fertilizer utilization and rice yield; the invention has a wide source of raw materials, is highly efficient and low in toxicity, is green and environmentally friendly, and can reduce environmental pollution while improving nitrogen fertilizer utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The NH in the soil of negative control group, positive control group, Example 5 group, Comparative Example 1 group and Comparative Example 2 group at different periods 4 + -N content curve.

[0026] Figure 2 It is a comparison chart of nitrification inhibition rate and urease inhibition rate of Example 5 group, Comparative Example 1 group and Comparative Example 2 group.

[0027] Figure 3 These are the SPAD value curves of rice leaves at different stages for the negative control group, the positive control group, Example 5, the comparative example 1 group, and the comparative example 2 group.

[0028] Figure 4It is a comparison chart of plant heights of the negative control group, the positive control group, Example 5 group, the comparative example 1 group, and the comparative example 2 group at different periods.

[0029] Figure 5 It is a comparison chart of the effective ear number and the number of grains per ear in the first season and the regeneration season of the negative control group, the positive control group, Example 5 group, the comparative example 1 group, and the comparative example 2 group.

[0030] Figure 6 It is a comparison chart of the thousand-grain weight and per-acre yield of the negative control group, the positive control group, Example 5 group, the comparative example 1 group, and the comparative example 2 group in the first season and the regeneration season.

[0031] Figure 7 It is a comparison chart of the nitrogen fertilizer contribution rate and the agronomic utilization rate of nitrogen fertilizer in the first season and the regeneration season for the negative control group, the positive control group, Example 5 group, the comparative example 1 group, and the comparative example 2 group. DETAILED DESCRIPTION

[0032] The present invention will be further explained below in conjunction with specific embodiments.

[0033] Example 1

[0034] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 100kg of urea, 50kg of ammonium chloride, 0.5kg of Bacillus subtilis agent, 1kg of chitosan, 1kg of lignin, 1kg of urea peroxide, 1kg of cellulose acetate, 1kg of polyvinyl alcohol, 1kg of fulvic acid, 10kg of natural clinoptilolite, 1kg of 3,4-dimethylpyrazole phosphate, 100g of berberine, 50g of nuciferine, and 5kg of chitosan acetic acid solution.

[0035] Chitosan acetic acid solution is obtained by adding chitosan to 0.5% acetic acid solution, and the mass ratio of chitosan to acetic acid solution is 1:10. The number of viable bacteria in the Bacillus subtilis inoculant is 1×10 7 cfu / g.

[0036] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0037] S1, adding chitosan, lignin and urea peroxide to 20 kg of 0.5% acetic acid solution, stirring at 120° C. for 1 min, and cooling to room temperature to obtain preform b;

[0038] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into it at a temperature of 50°C, continuing to stir for 5 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0039] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 100 kPa, to obtain a blank;

[0040] S4. Send the blank into a dryer for drying, the inlet temperature of the dryer is 150°C, the outlet temperature is 80°C, and then send it to a cooler for cooling, the outlet temperature of the cooler is 40°C, add it into the drum of the coating machine, spray chitosan acetic acid solution into it at a temperature of 50°C, continue to rotate for 5 minutes, discharge the material, and dry it in vacuum.

[0041] Example 2

[0042] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 120kg of urea, 70kg of ammonium chloride, 1.5kg of Bacillus subtilis agent, 3kg of chitosan, 3kg of lignin, 5kg of urea peroxide, 3kg of cellulose acetate, 3kg of polyvinyl alcohol, 2kg of fulvic acid, 12kg of natural clinoptilolite, 2kg of 3,4-dimethylpyrazole phosphate, 400g of berberine, 150g of nuciferine, and 15kg of chitosan acetic acid solution.

[0043] Chitosan acetic acid solution is obtained by adding chitosan to 1.2% acetic acid solution, and the mass ratio of chitosan to acetic acid solution is 3:20. The number of viable bacteria in the Bacillus subtilis inoculant is 3×10 7 cfu / g.

[0044] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0045] S1, adding chitosan, lignin and urea peroxide to 40 kg of 1.2% acetic acid solution, stirring at 150° C. for 3 min, and cooling to room temperature to obtain preform b;

[0046] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into the drum at a temperature of 60°C, continuing to stir for 10 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0047] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 115 kPa, to obtain a blank;

[0048] S4. Send the blank into a dryer for drying, the inlet temperature of the dryer is 150°C, the outlet temperature is 80°C, and then send it to a cooler for cooling, the outlet temperature of the cooler is 40°C, add it into the drum of the coating machine, spray chitosan acetic acid solution into it at a temperature of 60°C, continue to rotate for 10 minutes, discharge the material, and dry it in vacuum.

[0049] Example 3

[0050] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 105kg of urea, 55kg of ammonium chloride, 1.2kg of Bacillus subtilis agent, 2.5kg of chitosan, 1.3kg of lignin, 4kg of urea peroxide, 1.5kg of cellulose acetate, 2.5kg of polyvinyl alcohol, 1.3kg of fulvic acid, 10.5kg of natural clinoptilolite, 1.7kg of 3,4-dimethylpyrazole phosphate, 200g of berberine, 120g of nuciferine, and 8kg of chitosan acetic acid solution.

[0051] Chitosan acetic acid solution is obtained by adding chitosan to 1% acetic acid solution, and the mass ratio of chitosan to acetic acid solution is 1.5:18. The number of viable bacteria in the Bacillus subtilis inoculant is 1.5×10 7 cfu / g.

[0052] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0053] S1, adding chitosan, lignin and urea peroxide to 35 kg of 0.6% acetic acid solution, stirring at 140° C. for 1.5 min, and cooling to room temperature to obtain preform b;

[0054] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into the drum at a temperature of 58°C, continuing to stir for 7 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0055] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 110 kPa, to obtain a blank;

[0056] S4. Send the blank into a dryer for drying, the inlet temperature of the dryer is 150°C, the outlet temperature is 80°C, and then send it to a cooler for cooling, the outlet temperature of the cooler is 40°C, add it into the drum of the coating machine, spray chitosan acetic acid solution into it at a temperature of 52°C, continue to rotate for 9 minutes, discharge the material, and dry it in vacuum.

[0057] Example 4

[0058] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 115kg of urea, 65kg of ammonium chloride, 0.8kg of Bacillus subtilis agent, 1.5kg of chitosan, 1.7kg of lignin, 2kg of urea peroxide, 2.5kg of cellulose acetate, 1.5kg of polyvinyl alcohol, 1.7kg of fulvic acid, 11.5kg of natural clinoptilolite, 1.3kg of 3,4-dimethylpyrazole phosphate, 300g of berberine, 80g of nuciferine, and 12kg of chitosan acetic acid solution.

[0059] Chitosan acetic acid solution is obtained by adding chitosan to 0.6% acetic acid solution, and the mass ratio of chitosan to acetic acid solution is 2.5:12. The number of viable bacteria in the Bacillus subtilis inoculant is 2.5×10 7 cfu / g.

[0060] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0061] S1, adding chitosan, lignin and urea peroxide to 25 kg of 1% acetic acid solution, stirring at 130° C. for 2.5 min, and cooling to room temperature to obtain preform b;

[0062] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into the drum at a temperature of 52°C, continuing to stir for 9 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0063] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 105 kPa, to obtain a blank;

[0064] S4. Send the blank into a dryer for drying, the inlet temperature of the dryer is 150°C, the outlet temperature is 80°C, and then send it to a cooler for cooling, the outlet temperature of the cooler is 40°C, add it into the drum of the coating machine, spray chitosan acetic acid solution into it at a temperature of 52°C, continue to rotate for 9 minutes, discharge the material, and dry it in vacuum.

[0065] Example 5

[0066] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 110kg of urea, 60kg of ammonium chloride, 1kg of Bacillus subtilis agent, 2kg of chitosan, 1.5kg of lignin, 3kg of urea peroxide, 2kg of cellulose acetate, 2kg of polyvinyl alcohol, 1.5kg of fulvic acid, 11kg of natural clinoptilolite, 1.5kg of 3,4-dimethylpyrazole phosphate, 250g of berberine, 100g of nuciferine, and 10kg of chitosan acetic acid solution.

[0067] Chitosan acetic acid solution is obtained by adding chitosan to 0.8% acetic acid solution, and the mass ratio of chitosan to acetic acid solution is 2:15. The number of viable bacteria in the Bacillus subtilis inoculant is 2×10 7 cfu / g.

[0068] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0069] S1, adding chitosan, lignin and urea peroxide to 30 kg of 0.8% acetic acid solution, stirring at 135° C. for 2 min, and cooling to room temperature to obtain preform b;

[0070] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into the drum at a temperature of 55°C, continuing to stir for 8 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0071] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 108 kPa, to obtain a blank;

[0072] S4. Send the blank into a dryer for drying, the inlet temperature of the dryer is 150°C, the outlet temperature is 80°C, and then send it to a cooler for cooling, the outlet temperature of the cooler is 40°C, add it into the drum of the coating machine, spray chitosan acetic acid solution into it at a temperature of 55°C, continue to rotate for 8 minutes, discharge the material, and dry it in vacuum.

[0073] Comparative Example 1

[0074] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 110kg of urea, 60kg of ammonium chloride, 1kg of Bacillus subtilis agent, 2kg of chitosan, 2kg of cellulose acetate, 2kg of polyvinyl alcohol, 1.5kg of fulvic acid, 11kg of natural clinoptilolite, 1.5kg of 3,4-dimethylpyrazole phosphate, 250g of berberine, 100g of nuciferine, and 10kg of chitosan acetic acid solution.

[0075] Chitosan acetic acid solution is obtained by adding chitosan to 0.8% acetic acid solution, and the mass ratio of chitosan to acetic acid solution is 2:15. The number of viable bacteria in the Bacillus subtilis inoculant is 2×10 7 cfu / g.

[0076] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0077] S1, adding chitosan to 30 kg of 0.8% acetic acid solution and stirring for 2 min to obtain preform b;

[0078] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into the drum at a temperature of 55°C, continuing to stir for 8 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0079] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 108 kPa, to obtain a blank;

[0080] S4. Send the blank into a dryer for drying, the inlet temperature of the dryer is 150°C, the outlet temperature is 80°C, and then send it to a cooler for cooling, the outlet temperature of the cooler is 40°C, add it into the drum of the coating machine, spray chitosan acetic acid solution into it at a temperature of 55°C, continue to rotate for 8 minutes, discharge the material, and dry it in vacuum.

[0081] Comparative Example 2

[0082] A synergistic nitrogen fertilizer for regenerated rice, the raw materials of which include: 110kg urea, 60kg ammonium chloride, 1kg Bacillus subtilis agent, 2kg chitosan, 1.5kg lignin, 3kg urea peroxide, 2kg cellulose acetate, 2kg polyvinyl alcohol, 1.5kg fulvic acid, 11kg natural clinoptilolite, 1.5kg 3,4-dimethylpyrazole phosphate, 250g berberine, and 100g nuciferine. The number of viable bacteria in the Bacillus subtilis agent is 2×10 7 cfu / g.

[0083] The above-mentioned method for preparing the synergistic nitrogen fertilizer for regenerated rice comprises the following steps:

[0084] S1, adding chitosan, lignin and urea peroxide to 30 kg of 0.8% acetic acid solution, stirring at 135° C. for 2 min, and cooling to room temperature to obtain preform b;

[0085] S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, spraying the prefabricated material b into the drum at a temperature of 55°C, continuing to stir for 8 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer;

[0086] S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, natural clinoptilolite, 3,4-dimethylpyrazole phosphate, berberine and nuciferine uniformly, and sending the mixture into a rotary drum steam granulator for granulation, wherein the steam pressure is 108 kPa, to obtain a blank;

[0087] S4. Send the blank into a dryer for drying. The inlet temperature of the dryer is 150°C and the outlet temperature is 80°C. Then send it into a cooler for cooling. The outlet temperature of the cooler is 40°C.

[0088] A comparative test was conducted in Wuxue City, Huanggang City, Hubei Province. Hybrid rice variety Liangyou 6326 was used as the test variety. The planting method was transplanting, with sowing on March 25, transplanting on April 28, and harvesting on October 16.

[0089] The negative control group was set up without nitrogen fertilizer application, the positive control group was set up with farmers' usual fertilization, and Example 5 group, Comparative Example 1 group and Comparative Example 2 group were set up at the same time.

[0090] The specific fertilizer application of each group (based on pure amount per mu) is as follows:

[0091]

[0092] The nitrogen fertilizer used in the positive control group was pure urea, the nitrogen fertilizer used in Example 5 was the synergistic nitrogen fertilizer obtained in Example 5, the nitrogen fertilizer used in Comparative Example 1 was the synergistic nitrogen fertilizer obtained in Comparative Example 1, and the nitrogen fertilizer used in Comparative Example 2 was the synergistic nitrogen fertilizer obtained in Comparative Example 2.

[0093] A 15cm deep and 20cm wide ditch was dug around each plot, and a 35cm high and 50cm wide water-isolating ridge was built around the plot with the ditch soil, and the ridge was wrapped with plastic film. A 1m protection row was reserved between the plots to prevent water and fertilizer from flowing into each other. A separate water inlet and drainage ditch was set up in the experimental field to ensure that each plot was irrigated and drained separately. The field water management is to keep the seedlings moist during the seedling stage, maintain a shallow water layer (3-5cm) during the tillering stage, dry the field during the peak tillering stage, and alternate dry and wet water management in the later stage. According to the local high-yield cultivation and management measures for medium-season rice, diseases, insects, and weeds are strictly controlled throughout the growth period to prevent yield losses.

[0094] The whole process of soil NH 4 + -N was monitored, and soil NH 4 + -N as Figure 1 As shown, the NH 4 + -N has the smallest fluctuation and is more stable.

[0095] The average nitrification inhibition rate and average urease inhibition rate of the soil in the whole growth period of Example 5, Comparative Example 1 and Comparative Example 2 are as follows: Figure 2 As shown, the Example 5 group can effectively inhibit soil nitrification and urease, avoid the conversion and decomposition of nitrogen fertilizer, effectively maintain the content of available nitrogen in the soil, and ensure the absorption and utilization of regenerated rice.

[0096] Samples were taken from rice leaves at different stages and their SPAD values ​​were tested. Figure 3As shown, each group reached the highest value at the panicle differentiation stage, the leaf SPAD value decreased at the maturity stage of the first season, then increased at the heading stage of the regeneration season, and decreased at the maturity stage of the regenerated rice; and the SPAD value of Example 5 group was always higher than that of the other groups during the same period.

[0097] The height of rice plants was monitored at different stages, such as Figure 4 As shown, the plant height of each group in the first season was higher than that in the regeneration season; and in the same period, the plant height of the Example 5 group was always the highest.

[0098] The production of each group in the first season and the regeneration season is counted, such as Figure 5 and Figure 6 As shown, the number of effective panicles, number of grains per panicle, 1000-grain weight and yield per mu of the Example 5 group were better than those of the other groups, which proved that the synergistic nitrogen fertilizer obtained in Example 5 can effectively promote rice growth and increase rice yield.

[0099] The nitrogen fertilizer contribution rate and nitrogen fertilizer agronomic utilization rate of each group in the first season and the regeneration season were calculated, such as Figure 7 As shown, the nitrogen fertilizer contribution rate and nitrogen fertilizer agronomic utilization rate of Example 5 group are higher.

[0100] The applicant believes that the reason for the above results is that the present invention uses berberine and nuciferine to chelate with the central ion of urease, effectively inhibiting its catalytic effect. At the same time, it contains amino groups with a molecular structure similar to urea, which can produce competitive inhibition on urea hydrolysis, promote the absorption of nitrogen nutrients by crops, and improve the utilization rate of nitrogen fertilizer from the side. Urea is very soluble in water. The present invention first coats urea internally, which can effectively control the slow-release effect of urea; then chitosan acetic acid solution is used for coating, and it is cross-linked with internal cellulose acetate during the coating process. Not only does the particle have excellent hydrophilic and water-retaining properties, ensuring the slow release of internal substances, but it can also regulate the internal urea fertilizer effect period, greatly improving the fertilizer effect period and utilization rate of nitrogen fertilizer. The invention can improve the utilization efficiency of nitrogen fertilizer in rice planting, inhibit the decomposition of nitrogen fertilizers such as urea in the soil, effectively reduce the loss of nitrogen fertilizer in the soil, and has good biocompatibility. At the same time, it has good mechanical strength to maintain the gel form, which can increase the viscosity of nitrogen fertilizer, prolong the residence time of nitrogen fertilizer in the rice field, and avoid being washed away by water, thereby improving the use effect of the synergist.

[0101] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A synergistic nitrogen fertilizer for regenerated rice, characterized in that: The raw materials include, by mass: 100-120 parts of urea, 50-70 parts of ammonium chloride, 0.5-1.5 parts of Bacillus subtilis agent, 1-3 parts of chitosan, 1-3 parts of lignin, 1-5 parts of urea peroxide, 1-3 parts of cellulose acetate, 1-3 parts of polyvinyl alcohol, 1-2 parts of fulvic acid, 10-12 parts of silicon fertilizer, 1-2 parts of nitrification inhibitor, 0.1-0.4 parts of berberine, 0.05-0.15 parts of nuciferine, and 5-15 parts of chitosan acetic acid solution; The chitosan acetic acid solution is obtained by adding chitosan into an acetic acid solution with a mass fraction of 0.5-1.2%, and the mass ratio of the chitosan to the acetic acid solution is 1-3:10-20.

2. The synergistic nitrogen fertilizer for regenerated rice according to claim 1, characterized in that: Silicon fertilizer is natural clinoptilolite.

3. The synergistic nitrogen fertilizer for regenerated rice according to claim 2, characterized in that: The mass ratio of berberine to nuciferine is 10-15:4-6.

4. The synergistic nitrogen fertilizer for regenerated rice according to claim 1, characterized in that: The nitrification inhibitor was 3,4-dimethylpyrazole phosphate.

5. The synergistic nitrogen fertilizer for regenerated rice according to claim 1, characterized in that: The number of viable bacteria in the Bacillus subtilis inoculant is 1-3×10 7 cfu / g.

6. A method for preparing a synergistic nitrogen fertilizer for regenerated rice as claimed in claims 1 to 5, characterized in that: The steps include: S1, adding chitosan, lignin and urea peroxide to acetic acid solution, stirring at 120-150° C. for 1-3 min, and cooling to room temperature to obtain preform b; S2, adding urea, ammonium chloride and Bacillus subtilis agent into the drum of the coating machine, adjusting the temperature to 50-60°C, spraying the prefabricated material b therein, continuing to stir for 5-10 minutes, discharging the material, and vacuum drying to obtain the pretreated nitrogen fertilizer; S3, mixing the pretreated nitrogen fertilizer, cellulose acetate, polyvinyl alcohol, fulvic acid, silicon fertilizer, nitrification inhibitor, berberine and nuciferine uniformly, and granulating to obtain a blank; S4. Dry the blank, cool it, add it into the drum of the coating machine, adjust the temperature to 50-60°C, spray the chitosan acetic acid solution into it, continue to rotate for 5-10 minutes, discharge it, and dry it in vacuum.

7. The method for preparing a synergistic nitrogen fertilizer for regenerated rice according to claim 6, characterized in that: In S1, the mass fraction of the acetic acid solution is 0.5-1.2%.

8. The method for preparing a synergistic nitrogen fertilizer for regenerated rice according to claim 6, characterized in that: In S3, a rotary drum steam granulator is used for granulation, and the steam pressure is 100-115 kPa.

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