A method for improving nitrogen utilization efficiency of peanuts

Abstract

This invention belongs to the field of peanut cultivation and nitrogen use efficiency regulation technology. This invention provides a method for improving the nitrogen use efficiency of peanuts, comprising the following steps: applying a mixture of Bacillus preparation and water, along with a polyglutamic acid solution, to the rhizosphere via root irrigation during the initial flowering stage, and spraying a first composition onto the peanut leaves; spraying a second composition onto the peanut leaves during the full flowering stage; and spraying a third composition onto the peanut leaves during the pod-filling stage; and specifying the composition of the first, second, and third compositions. This invention improves the nitrogen use efficiency of peanuts by regulating the peanut rhizosphere environment and foliar nutrient supply in stages, promoting rhizosphere microbial activity, increasing the level of endogenous hormones in the roots, and enhancing the plant's ability to absorb, translocate, and distribute nitrogen. This invention has a clear regulatory approach, a complete technical route, and is applicable to the production of different peanut varieties.

Description

Technical Field

[0001] This invention relates to the field of peanut cultivation and nitrogen use efficiency regulation technology, and in particular to a regulation method for improving the nitrogen use efficiency of peanuts. Background Technology

[0002] Peanuts, as one of my country's important oilseed and cash crops, play a vital role in ensuring the supply of edible vegetable oil and promoting agricultural efficiency and income. Peanuts have a long growth period and complex nutrient requirements, especially nitrogen. Their nitrogen supply comes not only from soil inorganic nitrogen but also from nitrogen fixation through root nodules and the subsequent redistribution of nitrogen within the plant. However, in actual production, due to factors such as extensive fertilization management, an unreasonable nutrient supply structure, and changing environmental conditions, peanut nitrogen use efficiency is generally low. This manifests as a large input of nitrogen fertilizer but limited yield increase, with prominent problems of nitrogen residue and loss, affecting both economic benefits and posing certain ecological risks.

[0003] Currently, technical measures to improve nitrogen use efficiency in peanuts mainly focus on optimizing fertilization regimes, increasing the application of controlled-release fertilizers, and supplementing with micronutrients or spraying plant growth regulators. For example, the rational application of nitrogen, phosphorus, and potassium fertilizers, along with micronutrients, can improve the nutritional status of plants to some extent; spraying foliar fertilizers or plant growth regulators can promote photosynthesis or improve the seed setting rate. However, existing technologies often focus on the regulation of single stages, frequently implementing nutrient supplementation or regulation measures only at a specific growth stage, lacking systematic regulation of the entire process of nitrogen absorption, assimilation, and redistribution throughout the peanut's growth cycle.

[0004] From the perspective of the rhizosphere environment, peanut roots are highly sensitive to nitrogen forms in the soil and the rhizosphere microecological environment. Some existing technologies attempt to improve the rhizosphere environment by applying microbial agents or soil conditioners; however, in practical applications, they often fail to be tailored to the specific characteristics of peanut growth stages, resulting in insufficient connection between rhizosphere improvement measures and later nutrient requirements, and limited improvement in root absorption capacity. Furthermore, some technologies lack systematic optimization of the dosage, application timing, and supporting management measures for microbial agents, easily leading to unstable effects or a disconnect from later fertilization management.

[0005] In terms of foliar nutrition regulation, existing technologies mostly employ single foliar fertilizers or simple compound nutrient elements for supplementation, such as spraying magnesium, calcium, and zinc to improve leaf nutrition, or spraying plant growth regulators to promote flowering and pod formation. However, these measures often focus on short-term effects and do not adequately consider the differences in nitrogen metabolism requirements at different growth stages. For example, the plant's nitrogen requirements differ significantly at the initial flowering stage, full bloom stage, and fruit-filling stage. In the early stage, the focus is more on establishing root absorption and photosynthetic capacity; in the middle stage, the focus is more on the transport of assimilated products to reproductive organs; and in the later stage, the emphasis is more on nitrogen redistribution within the plant and kernel filling. Existing technologies lack a systematic approach for phased and continuous regulation centered on the core objective of "nitrogen use efficiency."

[0006] Furthermore, in actual production, nitrogen use efficiency depends not only on the amount of nitrogen fertilizer applied, but also on a variety of factors such as photosynthetic efficiency, enzyme activity levels, stress resistance, and nutrient transport capacity. Simply increasing nitrogen fertilizer input or applying it as a single foliar spray cannot fundamentally improve nitrogen absorption and deposition efficiency, and may even lead to excessive vegetative growth, increased risk of lodging, or decreased fruit set in the later stages. Some existing technologies, while increasing yield, have failed to consider the coordination of nitrogen absorption, assimilation, and deposition processes, resulting in a lack of significant improvement in nitrogen utilization efficiency within the plant.

[0007] Furthermore, different peanut varieties, growing environments, and climatic conditions significantly influence nitrogen absorption and utilization. If regulatory measures lack stage-specific targeting and dosage optimization, significant fluctuations in effectiveness can easily occur. Especially during the reproductive growth stage, plants become more sensitive to regulators and nutrients; improper dosage control can disrupt growth balance. Therefore, achieving precise regulation at different growth stages while ensuring safety is another challenge facing current technologies.

[0008] In summary, while existing technologies can improve peanut growth to some extent through fertilization management, microbial application, or foliar spraying, they still have the following shortcomings: First, they lack a systematic, phased regulation strategy centered on nitrogen use efficiency; second, there is a lack of continuous synergy among key stages such as rhizosphere absorption, leaf assimilation, and kernel deposition; third, various nutrient or regulatory measures are mostly applied at single points, failing to form a progressive management path throughout the entire growth period; and fourth, there is insufficient scientific control over the concentration and dosage of fertilizers, resulting in unstable effects or poor economic efficiency. Therefore, it is necessary to provide a technical solution that can provide phased regulation for different growth stages of peanuts and synergistically improve nitrogen use efficiency throughout the absorption-assimilation-redistribution process to overcome the shortcomings of existing technologies. Summary of the Invention

[0009] The purpose of this invention is to address the problems existing in the prior art, such as low nitrogen utilization efficiency in peanuts, single control measures, lack of continuous management across stages, and uncoordinated nitrogen absorption and utilization processes. It provides a staged method for improving nitrogen utilization efficiency in peanuts. By implementing targeted control measures at different growth stages, nitrogen absorption is enhanced, assimilation and transformation are promoted, and the later redistribution process is optimized, thereby improving the nitrogen utilization efficiency of peanuts.

[0010] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for regulating and improving the nitrogen use efficiency of peanuts, comprising the following steps: 1) At the initial flowering stage of peanuts, the mixture of Bacillus preparation and water, along with polyglutamic acid solution, is applied to the root zone by root irrigation, and the first composition is sprayed onto the peanut leaves. 2) During the peak flowering period of peanuts, spray the peanut leaves with the second composition; 3) During the peanut pod-filling stage, spray the peanut leaves with the third composition; The first composition comprises magnesium sulfate, calcium nitrate, and zinc sulfate; The second composition comprises chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid, and sodium alginate; The third composition includes amino acid ester, betaine, and a boron source.

[0011] Preferably, the Bacillus preparation in step 1) is Bacillus subtilis and / or Bacillus licheniformis, and the viable count of the Bacillus preparation is ≥1×10⁻⁶. 8 CFU / g, the application rate of Bacillus preparation is 0.5~1.2 kg / mu; The application rate of the mixture formed by mixing the Bacillus preparation with water is 30-50 L / mu.

[0012] Preferably, the mass fraction of the polyglutamic acid solution in step 1) is 0.02~0.05%, and the application rate of the polyglutamic acid solution is 30~50L / mu.

[0013] Preferably, in step 1), the first composition is an aqueous solution; wherein, based on the total mass of the first composition, the mass fractions of magnesium sulfate, calcium nitrate, and zinc sulfate are 0.15~0.25%, 0.1~0.2%, and 0.05~0.15%, respectively, and the remainder is water.

[0014] Preferably, in step 1), the application rate of the first composition is 35-40 L / mu.

[0015] Preferably, in step 2), the second composition is an aqueous solution; wherein, based on the total mass of the second composition, the mass fractions of chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid and sodium alginate are 0.00008~0.00015%, 0.03~0.05%, 0.001~0.003% and 0.02~0.04%, respectively, and the remainder is water.

[0016] Preferably, in step 2), the application rate of the second composition is 30-40 L / mu.

[0017] Preferably, the third composition in step 3) is an aqueous solution; wherein, based on the total mass of the third composition, the mass fractions of amino ester, betaine and boron source are 0.05~0.08%, 0.02~0.04% and 0.005~0.02%, respectively, and the remainder is water; The boron source is boric acid or borax; The application rate of the third composition is 40-45 L / mu.

[0018] As a preferred option, steps 1) to 3) are carried out sequentially according to the natural growth process of peanuts.

[0019] Preferably, the peanut variety is "Yuhua 37" or "Wanhua 2".

[0020] The beneficial effects of this invention include the following: 1) This invention, based on the physiological characteristics of peanuts at different growth stages, employs different regulatory compositions for phased regulation during the initial flowering, full bloom, and pod-filling stages. This allows for the seamless integration of improved rhizosphere environment, enhanced root vitality, and optimized nutrient distribution in the aboveground parts, thereby achieving continuous enhancement of nitrogen absorption, translocation, and utilization. Compared to conventional management, it significantly increases nitrogen accumulation in plant leaves, stems, and pods, enhancing nitrogen absorption capacity.

[0021] 2) This invention effectively promotes the activity of beneficial microorganisms, increases the activity of rhizosphere nitrogenase, and enhances the rhizosphere nitrogen transformation and supply capacity by applying a mixture of Bacillus preparation and water, as well as polyglutamic acid solution to the rhizosphere during the initial flowering stage. This improves the availability of soil nitrogen from the source and provides a continuous guarantee for plant nitrogen absorption.

[0022] 3) When the present invention is applied in conjunction with the regulatory composition during the full bloom period, it can significantly increase the content of root growth hormone (IAA) and the IAA / ZT ratio, optimize the balance of endogenous hormones in the root system, enhance root growth and nutrient absorption capacity, and improve the plant's nitrogen absorption efficiency.

[0023] 4) This invention promotes the rational distribution of nitrogen in the plant through phased foliar regulation measures, increases the proportion of nitrogen accumulation in pods, facilitates the transport of nitrogen to economic organs, and enhances nitrogen utilization.

[0024] 5) This invention achieves a systematic improvement in nitrogen absorption, translocation and utilization through a synergistic technical route of "rhizosphere regulation - root activation - foliar nutrition enhancement - stable yield promotion during the reproductive period", which improves the overall nitrogen utilization efficiency of peanuts and has significant agronomic application effects. Detailed Implementation

[0025] This invention provides a method for regulating and improving the nitrogen use efficiency of peanuts, comprising the following steps: 1) At the initial flowering stage of peanuts, the mixture of Bacillus preparation and water, along with polyglutamic acid solution, is applied to the root zone by root irrigation, and the first composition is sprayed onto the peanut leaves. 2) During the peak flowering period of peanuts, spray the peanut leaves with the second composition; 3) During the peanut pod-filling stage, spray the peanut leaves with the third composition; The first composition comprises magnesium sulfate, calcium nitrate, and zinc sulfate; The second composition comprises chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid, and sodium alginate; The third composition includes amino acid ester, betaine, and a boron source.

[0026] In this invention, the Bacillus preparation in step 1) is preferably Bacillus subtilis and / or Bacillus licheniformis; the viable count of the Bacillus preparation is preferably ≥1×10⁻⁶. 8 CFU / g, further preferably ≥1.5×10 8 CFU / g, more preferably ≥2×10 8 The preferred application rate of the Bacillus preparation is 0.5-1.2 kg / mu, more preferably 0.6-1 kg / mu, and even more preferably 0.8 kg / mu. The preferred application rate of the mixture formed by mixing the Bacillus preparation with water is 30-50 L / mu, more preferably 35-45 L / mu, and even more preferably 40 L / mu.

[0027] In this invention, applying Bacillus preparations at a rate of 0.5–1.2 kg / mu helps to balance colonization effectiveness with economic rationality. Bacillus preparations can form stable colonization communities in the rhizosphere and exert nutrient conversion and root-promoting effects. When the application rate is below 0.5 kg / mu, the number of bacteria is insufficient, the rhizosphere colonization density is low, and the effect on promoting nitrogen absorption is not significant; when the application rate exceeds 1.2 kg / mu, competition among bacteria intensifies, input costs increase, and the effect on improving nitrogen absorption tends to plateau.

[0028] In this invention, the mass fraction of the polyglutamic acid solution in step 1) is preferably 0.02~0.05%, more preferably 0.03~0.04%, and even more preferably 0.035%; the preferred amount of polyglutamic acid solution applied is... The concentration is 30-50 L / mu, more preferably 35-45 L / mu, and even more preferably 40 L / mu.

[0029] In this invention, a polyglutamic acid solution with a mass fraction of 0.02% to 0.05% can create a suitable rhizosphere environment for water and fertilizer retention. When the mass fraction is below 0.02%, the complexing and water-retention effects of polyglutamic acid are not significant; when the mass fraction is above 0.05%, the solution viscosity increases, which is not conducive to uniform application, and there is no significant increase in the effect of improving nitrogen absorption.

[0030] In this invention, step 1) the first composition is preferably an aqueous solution; wherein, based on the total mass of the first composition, the mass fractions of magnesium sulfate, calcium nitrate and zinc sulfate are preferably 0.15~0.25%, 0.1~0.2% and 0.05~0.15%, respectively, with the remainder being water, more preferably 0.18~0.22%, 0.14~0.16% and 0.1~0.14%, with the remainder being water, and more preferably 0.2%, 0.15% and 0.12%, with the remainder being water.

[0031] In this invention, the magnesium sulfate content in the first composition, ranging from 0.15% to 0.25%, can significantly supplement magnesium and enhance chlorophyll synthesis and photosynthetic capacity. Below 0.15%, the magnesium supplementation effect is limited; above 0.25%, the leaf surface salt concentration increases, which may affect the normal function of leaf stomata.

[0032] In this invention, the calcium nitrate content in the first composition, ranging from 0.1% to 0.2%, can supplement calcium and maintain leaf cell wall stability. Below 0.1%, the calcium supplementation effect is insufficient; above 0.2%, salt pressure increases, potentially affecting leaf absorption.

[0033] In this invention, the mass fraction of zinc sulfate in the first composition can be satisfied within the range of 0.05% to 0.15%. Sufficient zinc is required for enzyme activity and metabolic regulation. Below 0.05%, the promoting effect on leaf metabolism is not obvious; above 0.15%, the local zinc ion concentration in the leaves increases, which may cause a slight risk of phytotoxicity.

[0034] In this invention, the preferred application rate of the first composition in step 1) is 35-40 L / mu, more preferably 36-38 L / mu, and even more preferably 37 L / mu.

[0035] In this invention, spraying the first composition at a rate of 35-40 L / mu helps to improve nitrogen use efficiency while ensuring uniform foliar coverage. When the spraying rate is below 35 L / mu, the foliar coverage is insufficient, the distribution of the pesticide solution on the leaves is uneven, and the absorption of nutrients is affected. When the spraying rate is above 40 L / mu, pesticide runoff is likely to occur, increasing waste, and excessive leaf humidity may affect gas exchange and photosynthesis.

[0036] In this invention, during the initial flowering stage of peanut plants, as they transition from vegetative to reproductive growth, root vitality and the rhizosphere environment have a fundamental impact on subsequent nitrogen absorption and utilization. Applying a mixture of Bacillus preparation and water, along with a polyglutamic acid solution, to the rhizosphere at this stage can jointly improve the rhizosphere microecology and nutrient ion retention capacity, thus laying the foundation for nitrogen absorption. Specifically, the Bacillus preparation can colonize the rhizosphere and participate in the decomposition of organic matter and nutrient transformation, promoting root growth and root hair development, and enhancing the root system's ability to absorb inorganic nitrogen forms such as ammonium and nitrate nitrogen. Simultaneously, its metabolites help improve the rhizosphere environment, increasing root vitality and stress resistance. Polyglutamic acid, a high-molecular-weight substance with multiple carboxyl groups, possesses certain chelating / complexing and fertilizer / water retention capabilities, which can enhance the retention of rhizosphere nutrient ions (such as NH4+). + K + Ca 2+ Mg 2+ The controlled release of Bacillus preparations (such as polyglutamic acid) reduces the risk of leaching and helps improve rhizosphere moisture retention, thereby promoting sustained nitrogen absorption by roots. When Bacillus preparations are used in combination with polyglutamic acid, polyglutamic acid provides a more stable rhizosphere nutrient and moisture environment, which is conducive to stable microbial colonization. Microbial activity promotes nutrient conversion and root growth, thus forming a synergistic effect of "improved rhizosphere environment - enhanced root absorption".

[0037] Simultaneously, foliar spraying of the first composition (magnesium sulfate, calcium nitrate, and zinc sulfate) at the initial flowering stage can supplement essential nutrients closely related to nitrogen assimilation at the leaf level, enhancing photosynthetic capacity and the efficiency of key nitrogen metabolism processes. Magnesium, a central element of chlorophyll and involved in various enzymatic reactions, helps improve photosynthetic efficiency and carbon assimilation levels, providing energy and carbon skeleton support for nitrogen assimilation. Calcium participates in cell wall stability and membrane structure maintenance, improving leaf cell membrane stability and transport function. Meanwhile, nitrate, as one form of nitrogen, complements root absorption, helping to maintain leaf nitrogen metabolism and growth potential. Zinc, a micronutrient required for various enzyme and transcriptional regulation processes, promotes leaf metabolic activity and stress resistance, improving the stability of foliar absorption and assimilation processes. Foliar supplementation of Mg / Ca / Zn at the initial flowering stage can enhance leaf photosynthetic and metabolic activity, providing stronger "source" capacity for the full flowering period and subsequent pod formation stage, thus positively impacting the utilization efficiency of nitrogen after absorption.

[0038] In this invention, step 2) of the second composition is preferably an aqueous solution; wherein, based on the total mass of the second composition, the mass fractions of chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid, and sodium alginate are preferably 0.00008~0.00015%, 0.03~0.05%, 0.001~0.003%, and 0.02~0.04%, respectively, with the remainder being water; more preferably 0.0001~0.00014%, 0.035~0.045%, 0.0015~0.0025%, and 0.025~0.035%, with the remainder being water; and even more preferably 0.00012%, 0.04%, 0.002%, and 0.03%, with the remainder being water.

[0039] In this invention, the mass fraction of chlorpyrifos in the second composition, ranging from 0.00008% to 0.00015%, can promote cell division and floral development. Below 0.00008%, the regulatory effect is not significant; above 0.00015%, it may cause growth imbalance or excessive vegetative growth.

[0040] In this invention, the mass fraction of amino ester in the second composition, ranging from 0.03% to 0.05%, helps to enhance photosynthesis and nutrient transport. Below 0.03%, the physiological stimulation effect is insufficient; above 0.05%, the growth regulation effect tends to saturate.

[0041] In this invention, the mass fraction of 5-aminolevulinic acid in the second composition, ranging from 0.001% to 0.003%, can promote chlorophyll synthesis and electron transport efficiency. Below 0.001%, the promoting effect is limited; above 0.003%, there is no significant additional gain in photosynthesis.

[0042] In this invention, the sodium alginate content in the second composition, ranging from 0.02% to 0.04%, can improve leaf adhesion and physiological activity. Below 0.02%, the absorption-promoting effect is limited; above 0.04%, the solution viscosity increases, which is detrimental to spray uniformity.

[0043] In this invention, the spraying amount of the second composition in step 2) is preferably 30-40 L / mu, more preferably 34-36 L / mu, and even more preferably 35 L / mu.

[0044] In this invention, spraying the second composition at a rate of 30-40 L / acre helps to ensure both the regulatory effect and economic efficiency and application stability. When the spraying rate is below 30 L / acre, the amount adhering to the leaf surface is insufficient, which is not conducive to the uniform absorption of regulators and functional substances; when the spraying rate is above 40 L / acre, the flow of the pesticide solution increases, the effective absorption ratio per unit area decreases, and it may cause unnecessary increases in input costs.

[0045] In this invention, the peanut's peak flowering period is a critical window for flowering and pod formation, during which the plant's demand for assimilates and nitrogen increases rapidly. By spraying a second composition (chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid, and sodium alginate) during the peak flowering period, the conversion of nitrogen from absorption to effective utilization can be promoted by regulating the source-sink relationship, enhancing leaf physiological activity and substance transport capacity. Among them, chlorpyrifos belongs to the class of cytokinin regulators, which can promote cell division and organ development, improve the development potential of flowers and young fruits, and thus enhance the demand for sinks and the attraction of assimilates; aminoethyl esters can act as plant growth regulators to promote metabolism and physiological activity, help improve the photosynthetic efficiency and nutrient transport efficiency of leaves, and enhance the allocation of nutrients to reproductive organs; 5-aminolevulinic acid is one of the key precursors for chlorophyll / heme synthesis, which can enhance the synthesis of photosynthetic pigments and the efficiency of photosynthetic electron transport, thereby improving the carbon assimilation level and providing energy and carbon skeleton for nitrogen assimilation and amino acid synthesis; sodium alginate is a seaweed polysaccharide with certain colloidal properties and biostimulatory effects, which can improve leaf nutrient absorption and pesticide adhesion, and enhance plant stress resistance and metabolic stability, thereby improving the stability of regulatory treatments.

[0046] In this invention, the third composition in step 3) is preferably an aqueous solution; wherein, based on the total mass of the third composition, the mass fractions of amino ester, betaine, and boron source are preferably 0.05~0.08%, 0.02~0.04%, and 0.005~0.02%, respectively, with the remainder being water; more preferably 0.06~0.07%, 0.025~0.035%, and 0.01~0.015%, with the remainder being water; even more preferably 0.065%, 0.03%, and 0.012%, with the remainder being water. The boron source is preferably boric acid or borax.

[0047] In this invention, in the third composition, the mass fraction of aminoethyl ester in the range of 0.05% to 0.08% can delay leaf senescence and maintain photosynthetic function. Below 0.05%, the effect of maintaining the functional period is limited; above 0.08%, the regulatory effect tends to be stable.

[0048] In this invention, the betaine content in the third composition, ranging from 0.02% to 0.04%, helps enhance stress resistance and stabilize cell structure. Below 0.02%, the stress resistance-promoting effect is weak; above 0.04%, the osmotic regulation effect is no longer significantly enhanced.

[0049] In this invention, the boron source in the third composition, with a mass fraction ranging from 0.005% to 0.02%, can promote nutrient transport and kernel filling. Below 0.005%, the boron supplementation effect is limited; above 0.02%, it may increase the risk of boron accumulation.

[0050] In this invention, the application rate of the third composition is preferably 40-45 L / mu, more preferably 42-44 L / mu, and even more preferably 43 L / mu.

[0051] In this invention, the application rate of the third composition is in the range of 40-45 L / acre, which helps to improve the later control effect and maintain application safety. When the application rate is less than 40 L / acre, it is difficult to achieve sufficient coverage; when the application rate is more than 45 L / acre, the improvement in pesticide utilization is limited, and it is easy to increase residue and waste on the leaf surface.

[0052] In this invention, the peanut pod-filling stage is a period of rapid kernel filling and dry matter accumulation, during which the redistribution and translocation efficiency of nitrogen directly affects kernel filling and quality formation. By spraying a third composition (aminoethyl ester, betaine, and boron source) during the pod-filling stage, the effective redistribution of nitrogen to the kernel can be improved by enhancing stress resistance, maintaining leaf function, and improving transport and pod-filling processes. Specifically, continuing to spray aminoethyl ester during the pod-filling stage helps maintain leaf metabolic activity and photosynthetic function, promoting the continuous supply of assimilates and nitrogenous substances to the pods / kernels; betaine, a typical osmotic regulator, can enhance the plant's resistance to drought, heat, and other adverse conditions, stabilize cell membranes and enzyme activity, and slow down leaf senescence, thereby maintaining the plant's later assimilation and nitrogen metabolism capabilities; boron participates in cell wall formation, pollen tube growth, and sugar / assimilate transport processes, and supplementing boron during the pod-filling stage can improve nutrient transport and kernel filling processes, reduce the risk of empty shells and unfilled kernels, and improve later yield formation and quality stability. Through the synergistic effect of "metabolic maintenance (amino esters) + stress resistance and aging delay (betaine) + transport and fruit setting support (boron source)," the nitrogen redistribution efficiency during the fruit-filling period can be improved, enabling the nitrogen absorbed in the early stage to be more effectively converted and deposited into the kernel, thereby improving nitrogen utilization efficiency.

[0053] In this invention, steps 1) to 3) are preferably performed sequentially according to the natural growth process of peanuts.

[0054] In this invention, the preferred peanut variety is "Yuhua 37" or "Wanhua 2".

[0055] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0056] Example 1 The peanut variety "Yuhua 37" was selected for field trials. The experimental soil was loam, and the sowing density was 11,000 holes per mu. The base fertilizer was applied according to conventional methods, with 10 kg / mu of pure nitrogen, 8 kg / mu of phosphorus pentoxide, and 8 kg / mu of potassium oxide. During the peanut growth period, irrigation was carried out in a timely manner according to the soil moisture. Weeding was carried out once each during the seedling stage and before flowering. When pests and diseases occurred, conventional control measures were taken. Other field management was carried out according to conventional cultivation methods.

[0057] The peanut growth stages are determined according to the natural growth process: the initial flowering stage is when about 20% of the plants in the field show their first open flower; the peak flowering stage is when about 60% of the plants in the field are flowering; and the pod-filling stage is when the pods are basically full, the kernels are obviously enlarged, and the lower leaves begin to turn yellow.

[0058] When peanuts enter the initial flowering stage (35 days after sowing), proceed with step 1) according to the application rate per acre. First, weigh 1 kg of Bacillus subtilis (viable count 1.5 × 10⁻⁶). 8 Add CFU / g of the bacterial agent to water to prepare a 40L mixture, stirring thoroughly to ensure even dispersion. Then, weigh 12g of γ-polyglutamic acid, add water, and bring the volume to 30L to prepare a 0.04% polyglutamic acid solution. Finally, apply the Bacillus subtilis mixture and the polyglutamic acid solution together to the peanut root zone via root irrigation, ensuring the solution slowly seeps into the soil along the base of the plant without significant runoff.

[0059] On the same day, the first composition was sprayed onto the peanut leaves. The preparation method of the first composition is as follows: Dissolve 0.2 kg of magnesium sulfate, 0.15 kg of calcium nitrate, and 0.1 kg of zinc sulfate sequentially in water, and add water to a final volume of 100 L to obtain an aqueous solution of the first composition. Apply evenly using a backpack sprayer at a rate of 38 L per acre. Spraying should be done before 9:00 AM to ensure that the liquid is evenly applied to both sides of the leaves without dripping.

[0060] When peanuts enter their peak flowering stage (10 days after the initial flowering stage), spray the peanut leaves with the second composition. The second composition is prepared as follows: Weigh 0.1g of chlorpyrifos, 40g of aminoethyl ester, 2g of 5-aminolevulinic acid, and 30g of sodium alginate, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the second composition. Use a backpack sprayer to spray evenly at a rate of 35L per acre. Spraying should be done after 4:00 PM to ensure even coverage on both sides of the leaves without dripping.

[0061] When peanuts enter the pod-filling stage (12 days after full bloom), spray the peanut leaves with the third composition. The preparation method of the third composition is as follows: Weigh 60g of aminoethyl ester, 30g of betaine, and 15g of boric acid, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the third composition. Use a backpack sprayer to spray evenly at a rate of 42L per acre. Spraying time should be chosen after 4:00 PM to ensure even coverage of both sides of the leaves without dripping.

[0062] The above steps were all carried out sequentially according to the natural growth process of peanuts, without changing the conventional water and fertilizer management measures.

[0063] Example 2 The peanut variety "Wanhua No. 2" was selected for field trials. The experimental soil was loam, and the sowing density was 10,000 holes per mu. The base fertilizer was applied according to conventional methods, with 10 kg / mu of pure nitrogen, 8.5 kg / mu of phosphorus pentoxide, and 9 kg / mu of potassium oxide. During the peanut growth period, irrigation was carried out in a timely manner according to the soil moisture. Weeding was carried out once each during the seedling stage and before flowering. When pests and diseases occurred, conventional control measures were taken. Other field management was carried out according to conventional cultivation methods.

[0064] The peanut growth stages are determined according to the natural growth process: the initial flowering stage is when about 20% of the plants in the field show their first open flower; the peak flowering stage is when about 60% of the plants in the field are flowering; and the pod-filling stage is when the pods are basically full, the kernels are obviously enlarged, and the lower leaves begin to turn yellow.

[0065] When peanuts enter the initial flowering stage (32 days after sowing), proceed with step 1) according to the application rate per acre. First, weigh 1.2 kg of Bacillus licheniformis (viable count 1.8 × 10⁻⁶). 8 Add CFU / g of the bacterial agent to water to prepare a 50L mixture, stirring thoroughly to ensure even dispersion. Then, weigh 15g of γ-polyglutamic acid, add water, and bring the volume to 30L to prepare a 0.05% polyglutamic acid solution. Finally, apply the Bacillus subtilis mixture and the polyglutamic acid solution together to the peanut root zone via root irrigation, ensuring the solution slowly seeps into the soil along the base of the plant without significant runoff.

[0066] On the same day, the first composition was sprayed onto the peanut leaves. The preparation method for the first composition is as follows: Dissolve 0.15 kg of magnesium sulfate, 0.2 kg of calcium nitrate, and 0.05 kg of zinc sulfate in water sequentially, and then add water to a final volume of 100 L. The first aqueous solution was obtained. It was then applied evenly using a backpack sprayer at a rate of 40 L per acre. Spraying should be done before 9:00 AM to ensure that the liquid is evenly applied to both sides of the leaves without dripping.

[0067] When peanuts enter their peak flowering stage (9 days after the initial flowering stage), spray the peanut leaves with the second composition. The second composition is prepared as follows: Weigh 0.15g of chlorpyrifos, 30g of aminoethyl ester, 3g of 5-aminolevulinic acid, and 20g of sodium alginate, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the second composition. Apply evenly using a backpack sprayer at a rate of 30L per acre. Spraying should be done after 4:00 PM to ensure even coverage on both sides of the leaves without dripping.

[0068] When peanuts enter the pod-filling stage (10 days after full bloom), spray the peanut leaves with the third composition. The preparation method of the third composition is as follows: Weigh 50g of aminoethyl ester, 40g of betaine, and 20g of borax, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the third composition. Use a backpack sprayer to spray evenly at a rate of 40L per acre. Spraying time should be after 4:00 PM to ensure even coverage on both sides of the leaves without dripping.

[0069] The above steps were all carried out sequentially according to the natural growth process of peanuts, without changing the conventional water and fertilizer management measures.

[0070] Example 3 The peanut variety "Yuhua 37" was selected for field trials. The experimental soil was loam, and the sowing density was 11,000 holes per mu. The base fertilizer was applied according to conventional methods, with 10 kg / mu of pure nitrogen, 8 kg / mu of phosphorus pentoxide, and 8 kg / mu of potassium oxide. During the peanut growth period, irrigation was carried out in a timely manner according to the soil moisture. Weeding was carried out once each during the seedling stage and before flowering. When pests and diseases occurred, conventional control measures were taken. Other field management was carried out according to conventional cultivation methods.

[0071] Peanut growth stages are determined according to the natural growth process: the initial flowering stage is when about 20% of the plants in the field show signs of flowering. The first flower opens; the peak flowering period is when about 60% of the plants in the field are flowering; the fruit-filling period is when the pods are basically full, the kernels are obviously enlarged, and the lower leaves begin to turn yellow.

[0072] When peanuts enter the initial flowering stage (35 days after sowing), proceed with step 1) according to the application rate per acre. First, weigh 0.5 kg of Bacillus licheniformis (viable count 2.5 × 10⁻⁶). 8 Add CFU / g of Bacillus subtilis to water to prepare a 30L mixture, stirring thoroughly to ensure even dispersion of the inoculant. Then, weigh 10g of γ-polyglutamic acid, add water, and bring the volume to 50L to prepare a 0.02% polyglutamic acid solution. Finally, apply the Bacillus subtilis mixture and the polyglutamic acid solution together to the peanut root zone via root irrigation, ensuring the solution slowly seeps into the soil along the base of the plant without significant runoff.

[0073] On the same day, the first composition was sprayed onto the peanut leaves. The preparation method of the first composition is as follows: Dissolve 0.25 kg of magnesium sulfate, 0.1 kg of calcium nitrate, and 0.15 kg of zinc sulfate sequentially in water, and add water to a final volume of 100 L to obtain an aqueous solution of the first composition. Apply evenly using a backpack sprayer at a rate of 35 L per acre. Spraying should be done before 9:00 AM to ensure that the liquid is evenly applied to both sides of the leaves without dripping.

[0074] When peanuts enter their peak flowering stage (11 days after the initial flowering stage), spray the peanut leaves with the second composition. The second composition is prepared as follows: Weigh 0.08g of chlorpyrifos, 50g of aminoethyl ester, 1g of 5-aminolevulinic acid, and 40g of sodium alginate, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the second composition. Use a backpack sprayer to spray evenly at a rate of 40L per acre. Spraying should be done after 4:00 PM to ensure even coverage on both sides of the leaves without dripping.

[0075] When peanuts enter the pod-filling stage (12 days after full bloom), spray the peanut leaves with the third composition. The preparation method of the third composition is as follows: Weigh 80g of aminoethyl ester, 20g of betaine, and 5g of borax, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the third composition. Use a backpack sprayer to spray evenly at a rate of 45L per acre. Spraying time should be after 4:00 PM to ensure even coverage on both sides of the leaves without dripping.

[0076] The above steps were all carried out sequentially according to the natural growth process of peanuts, without changing the conventional water and fertilizer management measures.

[0077] Example 4 The peanut variety "Wanhua No. 2" was selected for field trials. The experimental soil was loam, and the sowing density was 10,000 holes per mu. The base fertilizer was applied according to conventional methods, with 10 kg / mu of pure nitrogen, 8.5 kg / mu of phosphorus pentoxide, and 9 kg / mu of potassium oxide. During the peanut growth period, irrigation was carried out in a timely manner according to the soil moisture. Weeding was carried out once each during the seedling stage and before flowering. When pests and diseases occurred, conventional control measures were taken. Other field management was carried out according to conventional cultivation methods.

[0078] The peanut growth stages are determined according to the natural growth process: the initial flowering stage is when about 20% of the plants in the field show their first open flower; the peak flowering stage is when about 60% of the plants in the field are flowering; and the pod-filling stage is when the pods are basically full, the kernels are obviously enlarged, and the lower leaves begin to turn yellow.

[0079] When peanuts enter the initial flowering stage (30 days after sowing), proceed with step 1) according to the application rate per acre. First, weigh 0.6 kg of Bacillus subtilis (viable count 1.5 × 10⁻⁶). 8 Add CFU / g of Bacillus subtilis to water to prepare a 40L mixture, stirring thoroughly to ensure even dispersion of the inoculant. Then, weigh 12g of γ-polyglutamic acid, add water, and bring the volume to 40L to prepare a 0.03% polyglutamic acid solution. Finally, apply the Bacillus subtilis mixture and the polyglutamic acid solution together to the peanut root zone via root irrigation, ensuring the solution slowly seeps into the soil along the base of the plant without significant runoff.

[0080] On the same day, the first composition was sprayed onto the peanut leaves. The preparation method of the first composition is as follows: dissolve 0.22 kg of magnesium sulfate, 0.16 kg of calcium nitrate, and 0.12 kg of zinc sulfate in water in sequence, and add water to make up to 100 L to obtain the aqueous solution of the first composition. Use a backpack sprayer to spray evenly, with a spraying rate of 38 L per acre. Spraying time should be selected before 9:00 am to ensure that the liquid is evenly applied to both sides of the leaves without dripping.

[0081] When peanuts enter their peak flowering stage (8 days after the initial flowering stage), spray the peanut leaves with the second composition. The second composition is prepared as follows: Weigh 0.12g of chlorpyrifos, 35g of aminoethyl ester, 2.5g of 5-aminolevulinic acid, and 25g of sodium alginate, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the second composition. Apply evenly using a backpack sprayer at a rate of 40L per acre. Spraying should be done after 4:00 PM to ensure even coverage on both sides of the leaves without dripping.

[0082] When peanuts enter the pod-filling stage (10 days after full bloom), spray the peanut leaves with the third composition. The preparation method of the third composition is as follows: Weigh 60g of aminoethyl ester, 35g of betaine, and 15g of boric acid, add water to a final volume of 100L, and stir thoroughly until completely dissolved to obtain an aqueous solution of the third composition. Use a backpack sprayer to spray evenly at a rate of 42L per acre. Spraying time should be chosen after 4:00 PM to ensure even coverage of both sides of the leaves without dripping.

[0083] The above steps were all carried out sequentially according to the natural growth process of peanuts, without changing the conventional water and fertilizer management measures.

[0084] Comparative Example 1 The peanut variety “Yuhua 37” was selected, and the field management was the same as in Example 1. During the initial flowering stage, the Bacillus spore mixture and polyglutamic acid solution were not applied; instead, the first, second, and third compositions were sprayed according to the method in Example 1, with the remaining steps being the same.

[0085] Comparative Example 2 During the initial flowering stage, only 1 kg of Bacillus subtilis was used to prepare a 40 L mixture for root irrigation, without applying polyglutamic acid solution. The remaining treatments were the same as in Example 1.

[0086] Comparative Example 3 The second composition was sprayed only during the peak flowering period, and the remaining treatments were the same as in Example 2.

[0087] Comparative Example 4 Only routine field management was carried out, without the regulatory treatment of Example 2.

[0088] To verify the effect of the regulation method of the present invention on improving nitrogen use efficiency in peanuts, Example 1 (variety "Yuhua 37") and Example 2 (variety "Wanhua 2") were used as treatment groups, and corresponding control experiments were conducted in proportion to each treatment. Each treatment had three replicate plots, each with an area of ​​no less than 30 m², arranged in a randomized block design. At maturity, nitrogen uptake and accumulation in plants, root endogenous hormone levels, and rhizosphere soil nitrogenase activity were measured, and the average values ​​of each indicator were taken from the replicate plots.

[0089] Sampling was conducted during the peanut maturation stage (when the pods were fully mature and the kernels hardened). Five uniformly growing plants were randomly selected from each plot, dug up along with their roots, and brought back to the laboratory. The plants were separated into three parts: leaves, stems, and pods. Surface impurities were quickly rinsed with clean water, and the plants were then dried. The samples were blanched at 105℃ for 30 minutes to kill the greening effect, and then transferred to a 75℃ forced-air drying oven to constant weight. Constant weight was defined as a difference of less than 0.01g between two consecutive weighings, and the dry weight of each part was recorded. The dried samples were pulverized using a high-speed grinder and sieved through a 60-mesh sieve (approximately 0.25mm in diameter) to obtain a uniform powder for later use.

[0090] Total nitrogen content in the plant was determined using the Kjeldahl method. 0.2 g of sieved sample powder was weighed into a digestion tube, and 10 mL of analytical grade concentrated sulfuric acid and 0.5 g of catalyst (a mixture of copper sulfate and potassium sulfate, with a mass ratio of 1:9) were added. The digestion tube was placed in a digestion furnace and gradually heated to 420 °C until the solution became clear and transparent. After cooling, the volume was adjusted to 50 mL, and the nitrogen content was calculated by distillation titration using a Kjeldahl apparatus. The nitrogen accumulation in each part was calculated from the dry matter mass and nitrogen content.

[0091] Root samples were collected during the peak flowering period. After removing the attached soil, the samples were immediately flash-frozen in liquid nitrogen and stored at -80°C. For analysis, the frozen root samples were thoroughly ground into powder under liquid nitrogen conditions. 0.5 g of the root powder was weighed and added to 10 mL of 80% methanol extract. Extraction was carried out with shaking at 4°C for 12 hours. The mixture was then centrifuged at 10,000 rpm for 10 min, and the supernatant was used for ELISA to determine the contents of auxin (IAA) and zeatin (ZT).

[0092] Rhizosphere nitrogenase activity was determined using the acetylene reduction method. Rhizosphere soil samples were collected during the full flowering period, and plant debris was removed before mixing. 10g of fresh soil was weighed and placed in a 120mL sealed culture bottle, which was then sealed with a rubber stopper. Air was evacuated from the bottle using a syringe, and acetylene gas was injected to achieve a volume fraction of 10%. The mixture was incubated at 25℃ for 1 hour. After incubation, the gas sample was extracted using a gas-tight syringe, and the ethylene production was determined using gas chromatography. The gas chromatography conditions were: column temperature 60℃, injection port temperature 100℃, and detector temperature 120℃. The amount of ethylene produced during incubation was calculated based on the ethylene standard curve and converted to nitrogenase activity using the following formula: Nitrogenase activity = Ethylene production ÷ Soil mass ÷ Incubation time, expressed in nmol C₂H₄·g¹·h. -1 .

[0093] (a) Yuhua No. 37 (Example 1 and Comparative Examples 1-2) Table 1 Nitrogen accumulation in plants

[0094] As shown in Table 1, the nitrogen accumulation in the leaves, stems and pods of Example 1 was higher than that in Comparative Examples 1 and 2, indicating that the regulation method of the present invention improved the plant's nitrogen absorption and transport capacity.

[0095] Table 2. Root plant hormone levels

[0096] As shown in Table 2, the root IAA and ZT contents of Example 1 are higher than those of Comparative Examples 1 and 2, indicating that the root activity is enhanced.

[0097] Table 3 Rhizosphere nitrogenase activity

[0098] As shown in Table 3, the nitrogenase activity in Example 1 was high, indicating that the rhizosphere nitrogen supply capacity was improved.

[0099] (ii) Wanhua No. 2 (Example 2 and Comparative Examples 3-4) Table 4 Nitrogen accumulation in plants

[0100] As shown in Table 4, Example 2 showed higher nitrogen accumulation in all parts than Comparative Examples 3-4, indicating that the regulation method of the present invention has an improving effect under different varieties and conditions.

[0101] Table 5. Hormone levels in root plants

[0102] As shown in Table 5, Example 2 showed higher levels of IAA and an IAA / ZT ratio than the control group, indicating that the balance of endogenous hormones in peanut roots was improved.

[0103] Table 6 Rhizosphere nitrogenase activity

[0104] As shown in Table 6, the nitrogenase activity in Example 2 was higher than that in the control example, indicating that the nitrogen supply capacity of peanut rhizosphere was improved.

[0105] A comparison of the two peanut varieties shows that, for both "Yuhua 37" and "Wanhua 2", the treatment in the example is superior to the corresponding treatment in terms of nitrogen absorption and accumulation in the plant, IAA content and IAA / ZT ratio, and rhizosphere nitrogenase activity. This indicates that the phased regulation method of the present invention can stably improve the efficiency of nitrogen absorption, translocation and utilization in peanuts, and has a wide range of applicable varieties and technical effects.

[0106] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for improving nitrogen use efficiency in peanut, the method comprising, Includes the following steps: 1) At the initial flowering stage of peanuts, the mixture of Bacillus preparation and water, along with polyglutamic acid solution, is applied to the root zone by root irrigation, and the first composition is sprayed onto the peanut leaves. 2) During the peak flowering period of peanuts, spray the peanut leaves with the second composition; 3) During the peanut pod-filling stage, spray the peanut leaves with the third composition; The first composition comprises magnesium sulfate, calcium nitrate, and zinc sulfate; The second composition comprises chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid, and sodium alginate; The third composition includes amino acid ester, betaine, and a boron source.

2. The regulation method according to claim 1, wherein the Bacillus preparation in step 1) is Bacillus subtilis and / or Bacillus licheniformis, the viable bacterial count of the Bacillus preparation is ≥ 1 x 10 8 CFU / g, and the application amount of the Bacillus preparation is 0.5-1.2 kg / acre. The application rate of the mixture formed by mixing the Bacillus preparation with water is 30-50 L / mu.

3. According to the control method of claim 1, the mass fraction of the polyglutamic acid solution in step 1) is 0.02~0.05%, and the application amount of the polyglutamic acid solution is 30~50L / mu.

4. The method of claim 1, wherein the first composition of step 1) is an aqueous solution; wherein, Based on the total mass of the first composition, the mass fractions of magnesium sulfate, calcium nitrate and zinc sulfate are 0.15~0.25%, 0.1~0.2% and 0.05~0.15%, respectively, with the remainder being water.

5. According to the control method of claim 4, in step 1), the spraying amount of the first composition is 35~40L / mu.

6. The method of claim 1, wherein the second composition of step 2) is an aqueous solution; wherein, Based on the total mass of the second composition, the mass fractions of chlorpyrifos, aminoethyl ester, 5-aminolevulinic acid and sodium alginate are 0.00008~0.00015%, 0.03~0.05%, 0.001~0.003% and 0.02~0.04%, respectively, with the remainder being water.

7. According to the control method of claim 6, in step 2), the spraying amount of the second composition is 30-40 L / mu.

8. The method of claim 1, wherein the third composition of step 3) is an aqueous solution; wherein, Based on the total mass of the third composition, the mass fractions of amino ester, betaine and boron source are 0.05~0.08%, 0.02~0.04% and 0.005~0.02%, respectively, with the remainder being water; The boron source is boric acid or borax; The application rate of the third composition is 40-45 L / mu.

9. According to the regulation method described in claim 1, steps 1) to 3) are implemented sequentially according to the natural growth process of peanut.

10. The regulation method according to claim 1, wherein the peanut variety is "Yuhua 37" or "Wanhua 2".

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