Potato green pesticide fertilizer based on phosphorus source substitution and preparation method

Abstract

The invention discloses a phosphorus source substitution-based potato green pesticide fertilizer and a preparation method thereof. The pesticide-fertilizer composition is a topdressing aqueous solution and comprises nitrogen (15-20 g / L), phosphorus (P2O5 accounts for 7-8 g / L, and phosphite accounts for 40%-50%) and potassium (K2O accounts for 10-15 g / L); the preparation method comprises the following steps: fully and uniformly mixing monopotassium phosphate, potassium nitrate, potassium phosphite, urea, potassium sulfate, magnesium sulfate, trace elements, an anti-blocking agent and the like with similar particle sizes to form three major element powder water-soluble fertilizers of 25-14-14, 19-19-19 and 14-8-30; the fertilizing method comprises the following steps: applying base fertilizer (15-15-15 compound fertilizer, 400-500 kg / ha) during planting, and carrying out drip irrigation topdressing (1000 L / ha, 5-10 times) after the seedling stage. The method can improve the potato yield, enhance the late blight resistance, significantly reduce the disease index of potato late blight, reduce the use of chemical pesticides, and promote the development of green agriculture.

Description

Technical Field

[0001] This invention relates to the field of agricultural fertilizer technology, specifically to a green fertilizer for potatoes based on phosphorus source substitution and its preparation method. Background Technology

[0002] Potatoes, the world's fourth largest food crop, hold significant economic and food security value in China. However, traditional fertilization methods often lead to nutrient excess or imbalance, causing soil acidification, nutrient loss, and environmental pollution. Furthermore, potatoes are susceptible to diseases such as late blight, which are highly contagious and destructive, severely impacting yield and quality. Current control methods include chemical pesticides, biological control, agronomic measures, and disease-resistant breeding. However, chemical pesticides easily lead to pathogen resistance and environmental pollution; biological control is costly and slow-acting; agronomic measures lack specificity; and disease-resistant breeding has a long cycle and poses biosafety risks.

[0003] In recent years, phosphites (such as potassium phosphite) have attracted attention due to their high solubility, rapid absorption, and combined nutritional and fungicidal functions. Phosphites can be transported through both the xylem and phloem of plants, inhibiting pathogens such as Phytophthora. However, research on the application of phosphites in potato production is still in its early stages. Current research and practice involve applying phosphites as a fungicide in addition to fertilization, using a separate foliar spray method; a systematic solution for optimizing phosphorus source ratios to balance nutrient supply and disease control is still lacking. Therefore, there is an urgent need for a green "fertilizer-pesticide" that integrates the nutritional and fungicidal functions of phosphites, reducing the input of chemical fertilizers and pesticides, and promoting the green and sustainable development of the potato industry. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the problems existing in the above-mentioned prior art and products, the inventors have proposed the present invention.

[0006] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a green fertilizer for potatoes based on phosphorus source substitution and its preparation method.

[0007] To solve the above technical problems, the present invention provides the following technical solution: a green fertilizer for potatoes based on phosphorus source substitution, wherein the fertilizer is a powder, which is dissolved into an aqueous solution before application, and contains nitrogen (N) at a concentration of 10-15 g / L after dissolution; The phosphorus source provides a total phosphorus pentoxide (P2O5) concentration of 7-8 g / L, which includes P2O5 provided by phosphate and P2O5 equivalent provided by phosphite, with the P2O5 equivalent provided by phosphite accounting for 40%-50% of the total P2O5. Potassium (K2O), concentration of 10-15 g / L.

[0008] As a preferred embodiment of the green fertilizer for potatoes based on phosphorus source substitution described in this invention, the nitrogen source is selected from urea, ammonium nitrate or a combination thereof, preferably urea, providing a nitrogen concentration of 15-17 g / L.

[0009] As a preferred embodiment of the green fertilizer for potatoes based on phosphorus source substitution described in this invention, the phosphate is selected from monoammonium phosphate or diammonium phosphate, preferably monoammonium phosphate, and provides a P2O5 concentration of 4-5 g / L.

[0010] As a preferred embodiment of the green fertilizer for potatoes based on phosphorus source substitution described in this invention, wherein the phosphite is potassium phosphite, providing a P2O5 equivalent concentration of 3-4 g / L.

[0011] As a preferred embodiment of the green fertilizer for potatoes based on phosphorus source substitution described in this invention, the potassium source is selected from potassium chloride, potassium sulfate, or a combination thereof, preferably potassium chloride, which, together with the potassium provided by potassium phosphite, provides a K2O concentration of 10-13 g / L.

[0012] A preferred embodiment of a method for preparing a green fertilizer for potatoes based on phosphorus source substitution includes the following steps: Potassium dihydrogen phosphate, potassium nitrate, potassium phosphite, urea, potassium sulfate, magnesium sulfate, trace elements, and anti-caking agents of similar particle size are thoroughly mixed. Weigh out the nitrogen source, phosphate, phosphite, and potassium source; Dissolve each raw material separately in water, mix them together, and add water to the target volume to prepare a solution with a nutrient concentration that meets the requirements.

[0013] As a preferred embodiment of the method for preparing a green fertilizer for potatoes based on phosphorus source substitution according to the present invention, wherein: the nitrogen source is urea, the phosphate is monoammonium phosphate, the phosphite is potassium phosphite, and the potassium source is potassium chloride, and the amounts are weighed in proportion to ensure that the phosphorus in the phosphite accounts for 40%-50% of the total P2O5.

[0014] A preferred embodiment of a green fertilizer application method for potatoes based on phosphorus source substitution, wherein: basal fertilizer is applied at planting time, the basal fertilizer is a compound fertilizer with an N-P2O5-K2O ratio of 15-15-15, and the application rate is 400-500 kg / ha. After the seedling stage, apply the fertilizer and pesticide through drip irrigation at a rate of 1000 L / ha each time.

[0015] As a preferred embodiment of the fertilization method for potato green fertilizer based on phosphorus source substitution according to the present invention, the topdressing fertilizer composition is applied 5-10 times, with an interval of 5-20 days between each application, preferably 7 times, with an interval of 7-15 days.

[0016] As described in this invention, a green fertilizer for potatoes based on phosphorus source substitution is used to simultaneously provide potato nutrition and control late blight, wherein: the fertilizer is applied by drip irrigation to enhance plant growth and reduce the incidence of late blight.

[0017] The beneficial effects of this invention are as follows: By introducing phosphite into topdressing, the nutrient supply to potatoes is optimized, promoting plant growth and increasing yield. The high solubility and rapid absorption of phosphite improve nutrient utilization efficiency, while its bactericidal function effectively inhibits late blight, reducing the use of chemical pesticides and lowering the risk of pathogen resistance. Compared to traditional fertilization methods, this invention significantly enhances plant height, stem diameter, and biomass accumulation, thereby improving stress resistance.

[0018] Furthermore, this fertilizer-pesticide improves soil pH and organic matter content, enhances soil fertility and microbial activity, and meets the requirements of green agriculture and sustainable development by reducing the input of chemical fertilizers. The drip irrigation method further improves nutrient utilization efficiency, reduces nutrient loss, and is environmentally friendly, providing a new approach for the green development of the potato industry. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0022] Example 1

[0023] This embodiment provides a green fertilizer for potatoes based on phosphorus source substitution and its preparation method.

[0024] Specifically, the phosphorus replacement rate for phosphite is 40%.

[0025] In this embodiment, a preferred liquid fertilizer composition for potatoes is provided, which is prepared by mixing the following components into a powder and then dissolving it in water to obtain a 1000-liter solution.

[0026] Nitrogen (N): 16.48 g / L

[0027] Phosphorus (P2O5): 7.74 g / L, of which phosphate P2O5 is 4.644 g / L (60%) and phosphite P2O5 equivalent is 3.096 g / L (40%). Potassium (K₂O): 12.21 g / L; Raw materials (per 1000 L solution): Urea (containing 46% N): 33.9 kg, providing 15.594 kg of N. Monoammonium phosphate (containing 11% N and 61% P2O5): 8.93 kg, providing 4.644 kg of P2O5 and 0.982 kg of N; Potassium phosphite (containing 58% P2O5 equivalent and 38% K2O): 10.32 g / L, providing 3.096 g / L of P2O5 equivalent and 2.064 g / L of K2O.

[0028] Potassium sulfate (containing 52% K2O): 16.91 g / L, providing 10.146 g / L of K2O.

[0029] Potassium dihydrogen phosphate, potassium nitrate, potassium phosphite, urea, potassium sulfate, magnesium sulfate, trace elements, and anti-caking agents of similar particle size are thoroughly mixed to form two sets of water-soluble powder fertilizers targeting different soil nutrient conditions: 25-14-14+14-8-30; or 19-19-19+14-8-30. Application method: Base fertilizer: Apply compound fertilizer (Yunnan Xiangfeng Fertilizer Co., Ltd.) with an N-P2O5-K2O ratio of 15-15-15 at the time of planting, at a rate of 450 kg / ha, with N, P2O5 and K2O inputs of 67.5 kg / ha, 67.5 kg / ha and 67.5 kg / ha respectively.

[0030] Topdressing: After the potato seedling stage, apply the above two topdressing solutions at 1000 L / ha through the drip irrigation system, for a total of 7 times, with an interval of 7-15 days between each application. The application time should be adjusted according to the potato growth stage (such as seedling stage, tuber formation stage, and tuber enlargement stage).

[0031] Specific topdressing amounts: Based on different soil nutrient conditions, the first topdressing plan is as follows: First topdressing (25-14-14) 5 kg / mu (75 kg / ha), second topdressing (25-14-14) 6.5 kg / mu (97.5 kg / ha), third topdressing (25-14-14) 7.7 kg / mu (115.5 kg / ha), fourth topdressing (14-8-30) 7 kg / mu (105 kg / ha), fifth topdressing (14-8-30) 7 kg / mu (105 kg / ha), sixth topdressing 8 kg / mu (120 kg / ha), seventh topdressing 8 kg / mu (120 kg / ha), with the final concentration diluted 300-500 times.

[0032] The second topdressing plan is as follows: First topdressing (19-19-19) 7 kg / mu (105 kg / ha), second topdressing (calcium ammonium nitrate) 13.5 kg / mu (202.5 kg / ha), third topdressing (19-19-19) 8 kg / mu (120 kg / ha), fourth topdressing (14-8-30) 7 kg / mu (105 kg / ha), fifth topdressing (14-8-30) 7 kg / mu (105 kg / ha), sixth topdressing (7.5 kg / mu (112.5 kg / ha), seventh topdressing (8 kg / mu (120 kg / ha), with the final concentration diluted 300-500 times.

[0033] After trials in different plots, both topdressing methods significantly promoted potato plant growth, increased plant height and stem diameter, improved nutrient absorption efficiency, increased tuber yield, reduced late blight disease index, reduced chemical pesticide use, and improved soil health.

[0034] Example 2

[0035] This embodiment provides a green fertilizer for potatoes based on phosphorus source substitution and its preparation method.

[0036] Specifically, the phosphorus replacement rate for phosphite was 46%.

[0037] Preparation of topdressing solution: Target nutrient concentration (per 1000 L solution): Nitrogen (N): 16.48 g / L Phosphorus (P2O5): 7.74 g / L, of which phosphate P2O5 is 4.177 g / L (54%) and phosphite P2O5 equivalent is 3.558 g / L (46%). Potassium (K₂O): 12.21 g / L; Raw materials (per 1000 L solution): Urea (containing 46% N): 33.9 kg, providing 15.594 kg of N. Monoammonium phosphate (containing 11% N and 61% P2O5): 8.03 kg, providing 4.177 kg of P2O5 and 0.883 kg of N. Potassium phosphite (containing 58% P2O5 equivalent and 38% K2O): 11.86 kg, providing 3.558 kg of P2O5 equivalent and 2.372 kg of K2O; Potassium sulfate (containing 52% K₂O): 16.40 kg, providing 9.84 kg of K₂O; Preparation steps: Potassium dihydrogen phosphate, potassium nitrate, potassium phosphite, urea, potassium sulfate, magnesium sulfate, trace elements, and anti-caking agents of similar particle size are thoroughly mixed to form three types of water-soluble powder fertilizers containing macro-elements: 25-14-14, 19-19-19, and 14-8-30. Application method: Base fertilizer: Same as in Example 1, apply 450 kg / ha of 15-15-15 compound fertilizer.

[0038] Topdressing: Same as in Example 1, apply 1000 L / ha topdressing solution by drip irrigation, for a total of 7 times, with an interval of 7-15 days.

[0039] Specific topdressing amounts: Based on different soil nutrient conditions, the first topdressing plan is as follows: First topdressing (25-14-14) 5 kg / mu (75 kg / ha), second topdressing (25-14-14) 6.5 kg / mu (97.5 kg / ha), third topdressing (25-14-14) 7 kg / mu (105 kg / ha), fourth topdressing (14-8-30) 7 kg / mu (105 kg / ha), fifth topdressing (14-8-30) 7 kg / mu (105 kg / ha), sixth topdressing 8 kg / mu (120 kg / ha), seventh topdressing 8 kg / mu (120 kg / ha), with the final concentration diluted 300-500 times.

[0040] The second topdressing plan is as follows: First topdressing (19-19-19) 7 kg / mu (105 kg / ha), second topdressing (calcium ammonium nitrate) 13.5 kg / mu (202.5 kg / ha), third topdressing (19-19-19) 8 kg / mu (120 kg / ha), fourth topdressing (14-8-30) 7 kg / mu (105 kg / ha), fifth topdressing (14-8-30) 7 kg / mu (105 kg / ha), sixth topdressing (7.5 kg / mu (112.5 kg / ha), seventh topdressing (8 kg / mu (120 kg / ha), with the final concentration diluted 300-500 times.

[0041] This phosphorus source substitution ratio formula optimizes the balance between nutrition and disease resistance, significantly improves plant growth indicators (such as plant height, stem diameter and biomass), enhances plant antioxidant capacity, significantly reduces late blight disease index, and increases yield; it also effectively reduces the use of chemical pesticides and improves soil health.

[0042] Example 3

[0043] This embodiment provides a green fertilizer for potatoes based on phosphorus source substitution and its preparation method.

[0044] Furthermore, the phosphorus replacement rate for phosphite is 50%.

[0045] Preparation of topdressing solution: Target nutrient concentration (per 1000 L solution): Nitrogen (N): 16.48 g / L Phosphorus (P2O5): 7.74 g / L, of which phosphate P2O5 is 3.87 g / L (50%) and phosphite P2O5 equivalent is 3.87 g / L (50%). Potassium (K₂O): 12.21 g / L; Raw materials (per 1000 L solution): Urea (containing 46% N): 33.9 kg, providing 15.594 kg of N. Monoammonium phosphate (containing 11% N and 61% P2O5): 7.44 kg, providing 3.87 kg of P2O5 and 0.818 kg of N; Potassium phosphite (containing 58% P2O5 equivalent and 38% K2O): 12.90 kg, providing 3.87 kg of P2O5 equivalent and 2.58 kg of K2O; Potassium sulfate (containing 52% K₂O): 16.05 kg, providing 9.63 kg of K₂O; Preparation steps: Potassium dihydrogen phosphate, potassium nitrate, potassium phosphite, urea, potassium sulfate, magnesium sulfate, trace elements, and anti-caking agents of similar particle size are thoroughly mixed to form two sets of water-soluble powder fertilizers targeting different soil nutrient conditions: 25-14-14+14-8-30; or 19-19-19+14-8-30. Application method: Base fertilizer: Same as in Example 1, apply 450 kg / ha of 15-15-15 compound fertilizer.

[0046] Topdressing: Same as in Example 1, apply 1000 L / ha topdressing solution by drip irrigation, for a total of 7 times, with an interval of 7-15 days.

[0047] Specific topdressing amounts: Based on different soil nutrient conditions, the first topdressing plan is as follows: First topdressing (25-14-14) 5 kg / mu (75 kg / ha), second topdressing (25-14-14) 6.5 kg / mu (97.5 kg / ha), third topdressing (25-14-14) 7.7 kg / mu (115.5 kg / ha), fourth topdressing (14-8-30) 7 kg / mu (105 kg / ha), fifth topdressing (14-8-30) 7 kg / mu (105 kg / ha), sixth topdressing 8 kg / mu (120 kg / ha), seventh topdressing 8 kg / mu (120 kg / ha), with the final concentration diluted 300-500 times.

[0048] The second topdressing plan is as follows: First topdressing (19-19-19) 7 kg / mu (105 kg / ha), second topdressing (calcium ammonium nitrate) 13.5 kg / mu (202.5 kg / ha), third topdressing (19-19-19) 8 kg / mu (120 kg / ha), fourth topdressing (14-8-30) 7 kg / mu (105 kg / ha), fifth topdressing (14-8-30) 7 kg / mu (105 kg / ha), sixth topdressing (7.5 kg / mu (112.5 kg / ha), seventh topdressing (8 kg / mu (120 kg / ha), with the final concentration diluted 300-500 times.

[0049] This formula further enhances disease resistance while maintaining sufficient nutrient supply, promoting robust plant growth, increasing yield, significantly reducing late blight disease index, reducing the input of chemical pesticides, and improving the soil environment.

[0050] This invention achieves a synergistic effect of nutrient supply and late blight control by introducing phosphite (a partial substitute for phosphate) into potato topdressing. This not only optimizes the potato growing environment but also provides a new approach for green agriculture. Phosphite not only participates in plant metabolism as a nutrient element but also significantly reduces the occurrence of late blight by directly inhibiting pathogens and inducing plant disease resistance. This dual function represents a qualitative leap forward compared to traditional fertilizers, providing technical support for the sustainable development of the potato industry.

[0051] Three embodiments demonstrate the flexibility and operability of the technical solution with phosphite replacement rates of 40%, 46%, and 50%, respectively. Each embodiment details the selection of raw materials, the formulation process, and the fertilization method, ensuring full disclosure and reproducibility of the technical solution. The different replacement rates reflect adaptability in practical applications, allowing adjustments based on soil type, climate conditions, or potato variety. The gradual variation in the phosphite ratio (40%-50%) not only validates the effectiveness of the technology but also provides a theoretical basis for optimizing fertilization programs. Whether at lower (40%) or higher (50%) replacement rates, this invention maintains a balance between nutrient supply and disease control.

[0052] From a plant physiology perspective, phosphites and phosphates exhibit significantly different mechanisms of action within plants. Phosphates primarily participate in nucleic acid synthesis and energy metabolism, while phosphites enhance antioxidant capacity and mitigate oxidative stress caused by diseases by activating the plant's defense system. Phosphites may scavenge free radicals and protect plant cells from pathogens by inducing the activity of antioxidant enzymes (such as superoxide dismutase and peroxidase). Furthermore, phosphites can directly act on pathogens, disrupting their cell membrane structure and inhibiting their growth and reproduction. This multi-layered disease prevention mechanism gives this invention a significant advantage in controlling late blight, especially when reducing the use of chemical pesticides.

[0053] Furthermore, drip irrigation systems ensure efficient nutrient utilization and reduce nutrient loss and environmental pollution by precisely controlling the amount and frequency of fertilizer application. Compared to traditional broadcast or fertigation, drip irrigation delivers nutrients directly to the root zone, optimizing the nutritional needs of potatoes during the seedling, tuber formation, and tuber enlargement stages. This precise fertilization method, combined with basal fertilizer, forms a complete nutrient management system, guaranteeing high yield and quality potatoes. Simultaneously, drip irrigation technology helps reduce surface salt accumulation, improves soil structure, and promotes root development.

[0054] From a soil ecology perspective, reducing the input of chemical fertilizers and pesticides significantly improves soil health. Traditional fertilization methods often lead to soil acidification and nutrient imbalances, while this invention, by optimizing the phosphorus source ratio, maintains soil pH and organic matter content, and enhances the diversity of beneficial soil microorganisms. Soil microorganisms are key factors in soil fertility and plant health. By reducing the proportion of pathogens (such as Phytophthora), enhancing the activity of beneficial bacteria (such as Pseudomonas and Bacillus), the soil microecology is improved. This optimization of the soil environment not only supports sustained high potato yields but also provides a reference for the green production of other crops.

[0055] From an operability and implementation perspective, this "fertilizer-pesticide" formula achieves an organic combination of fertilizer and pesticide through phosphorus source substitution, enabling disease control simultaneously with fertilization, achieving "one application, dual effects." This integrated application method significantly simplifies field management processes, reduces the labor and time required for separate pesticide spraying, lowers pesticide usage frequency and environmental risks, and improves the efficiency of simultaneous fertilization and disease prevention, providing practical technical advantages for green and efficient agricultural production. In summary, this invention achieves the dual goals of nutrient supply and disease control through a phosphorus source substitution mechanism, providing an innovative solution for the green development of the potato industry. The three embodiments, from the perspective of different substitution ratios, comprehensively demonstrate the feasibility and superiority of the technical solution. Whether from the perspectives of plant physiology, fertilization technology, or soil ecology, this invention reflects profound technical foundation and broad application prospects, pointing the way for the sustainable development of modern agriculture.

[0056] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A potato green chemical fertilizer based on phosphorus source substitution, characterized by: The medicine fertilizer is powder, dissolved into aqueous solution for application, comprising: nitrogen (N), the concentration after dissolution is 10-15 g / L; phosphorus source, providing total concentration of 7-8 g / L of P2O5, wherein the P2O5 equivalent provided by phosphite accounts for 40%-50% of the total P2O5; Potassium (K2O), concentration is 10-15 g / L.

2. A potato green color fertilizer based on phosphorus source substitution according to claim 1, characterized in that: The nitrogen source is selected from urea, ammonium nitrate or a combination thereof, preferably urea, which provides a nitrogen concentration of 15-17 g / L after dissolution.

3. The potato green chemical fertilizer based on phosphorus source substitution according to claim 1, characterized in that: The phosphate is selected from monoammonium phosphate or diammonium phosphate, preferably monoammonium phosphate, which provides a P2O5 concentration of 4-5 g / L after dissolution.

4. The potato green chemical fertilizer based on phosphorus source substitution according to claim 1, characterized in that: The phosphite is potassium phosphite, which provides a P2O5 equivalent concentration of 3-4 g / L after dissolution.

5. The potato green chemical fertilizer based on phosphorus source substitution according to claim 1, characterized in that: The potassium source is selected from potassium chloride, potassium sulfate or a combination thereof, preferably potassium chloride, which, in combination with the potassium provided by potassium phosphite, provides a K2O concentration of 10-13 g / L after dissolution.

6. The method for preparing potato green chemical fertilizer based on phosphorus source substitution according to claim 1, characterized in that: The method comprises the following steps: Weighing the nitrogen source, phosphate, phosphite and potassium source; Dissolve each raw material in water, mix and add water to the target volume to prepare a solution with nutrient concentration meeting the requirements of claim 1.

7. A method for preparing a potato green color fertilizer based on phosphorus source substitution according to claim 6, characterized in that: The nitrogen source is urea, the phosphate is monoammonium phosphate, the phosphite is potassium phosphite, and the potassium source is potassium chloride, which are weighed in proportion to meet the requirement that phosphite phosphorus accounts for 40%-50% of the total P2O5.

8. A potato green medicine fertilizer application method based on phosphorus source replacement, characterized in that: Base fertilizer is applied at planting, and the base fertilizer is a compound fertilizer with N-P2O5-K2O ratio of 15-15-15, and the application amount is 400-500 kg / ha; The aqueous solution of the medicine fertilizer after dissolution is applied by drip irrigation after the seedling stage, and the application amount is 1000 L / ha each time.

9. The fertilization method for potato green fertilizer based on phosphorus source substitution as described in claim 8, characterized in that: The medicine fertilizer is applied 5-10 times, with an interval of 5-20 days, preferably 7 times, with an interval of 7-15 days.

10. The use of a green fertilizer for potatoes based on phosphorus source substitution as described in claim 1 in simultaneously providing potato nutrition and controlling late blight, characterized in that: The aqueous solution of the medicine fertilizer after dissolution is applied by drip irrigation, which enhances plant growth and reduces the incidence of late blight.