Simple and efficient melon nitrogenous fertilizer recommended fertilization method

Abstract

The invention relates to a simple and efficient melon nitrogenous fertilizer recommended fertilization method which is carried out according to the following steps: (1) determining the target yield of melons; (2) determining yield reaction of nitrogen; (3) determining the agronomic efficiency of the nitrogen fertilizer: calculating the corresponding agronomic efficiency of the nitrogen fertilizer according to a formula after the reaction of obtaining the nitrogen yield in the step (2); and (4) determining the application amount of the nitrogen fertilizer: obtaining the yield reaction and the agronomic efficiency through the above steps, and obtaining the application amount of the nitrogen fertilizer in the melon field according to a formula: nitrogen application amount (FN, kg N / ha) = yield reaction (t / ha) * 1000 / agronomic efficiency (kg / kg). The simple and efficient melon nitrogenous fertilizer recommended fertilization method disclosed by the invention is simple to operate, can be used in the presence or absence of a soil test, can more reasonably recommend the application amount of the nitrogenous fertilizer for farmers, and reduces the influence of the nitrogenous fertilizer on the environment while improving the utilization rate of the nitrogenous fertilizer. Compared with melon farmers who are habitually fertilized to obtain melon yield benefit, the cotton yield benefit obtained by using the fertilization method disclosed by the invention is remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural planting, and in particular relates to a simple and efficient method for recommending nitrogen fertilizer application for melons. Background Art

[0002] Melon is one of the top ten fruits in the world. Melon likes fertilizer, and sufficient and reasonable nutrient supply is the guarantee of high-quality and high-yield melon. Nitrogen fertilizer is an important factor in determining the yield and quality of crops, and it is also the chemical fertilizer with the largest application amount in agricultural production. However, in actual production, melon farmers often blindly increase the application of chemical fertilizers in order to achieve higher economic benefits, especially the application of nitrogen fertilizers. There is a lot of arbitrariness. The supply of nitrogen fertilizer does not match the nitrogen requirement of melons at different stages, and the nitrogen fertilizer effect cannot be fully exerted, resulting in reduced nitrogen fertilizer utilization, increased melon planting costs, reduced planting benefits, and a series of environmental problems such as eutrophication of water bodies. In terms of recommended fertilization methods for melon fields, soil testing and formula fertilization is a more commonly used recommended fertilization method for melon fields. However, soil testing and formula fertilization currently also faces many problems, such as high requirements for soil testing technology and equipment, large differences in soil nutrients between farmers' plots, poor real-time performance of recommended effects, different melon varieties in different regions respond differently to fertilizers, and it is difficult to accurately test soil formulas. Therefore, it has become a technical problem that needs to be urgently solved by technicians in this field to establish a simple and fast recommended nitrogen fertilizer application method for melon based on yield response and agronomic efficiency to provide a scientific basis for rational fertilization of melon and high-quality development of the industry. Summary of the invention

[0003] The invention provides a simple and efficient method for recommending nitrogen fertilizer application for melons. The method obtains a relationship equation between the yield response of melons and agronomic efficiency through statistical analysis of a large amount of field test data in the early stage. The yield response is determined according to the soil nutrient grade and target yield of the melon field. The nitrogen application amount is determined according to the relationship between the nitrogen yield response and the agronomic efficiency of nitrogen fertilizer. The recommended nitrogen fertilizer amount is obtained in combination with the best nutrient management principle, thereby achieving scientific guidance on the application of nitrogen fertilizer in melon fields, improving the utilization rate of nitrogen fertilizer and the planting benefits of melon farmers, and promoting the healthy development of the melon industry.

[0004] The present invention is realized by the following technical scheme: a simple and efficient method for recommending nitrogen fertilizer application for melon, which is carried out according to the following method:

[0005] Step (1) Determine the target yield of melon: target yield (t / ha) = yield obtained in previous years or the previous year × 1.1;

[0006] Step (2) determines the nitrogen yield response: it refers to the difference in yield between the nitrogen fertilizer treatment and the nitrogen deficiency treatment: (a) If the nitrogen yield response of melon is known, then proceed directly to the solution of the following step (3); (b) If the yield response of melon nitrogen is unknown, the soil nutrient grade is determined based on the following soil test data. The soil nutrient grade classification principle is: low-fertility melon field soils have an organic matter content of ≤1.5%, available nitrogen content of ≤60 mg / kg, available phosphorus content of ≤10 mg / kg, and available potassium content of ≤100 mg / kg; medium-fertility melon field soils have an organic matter content of 1.5% to 2.5%, available nitrogen content of 60 mg / kg to 90 mg / kg, available phosphorus content of 10 mg / kg to 20 mg / kg, and available potassium content of 100 mg / kg to 180 mg / kg; high-fertility melon field soils have an organic matter content of ≥2.5%, available nitrogen content of ≥90 mg / kg, available phosphorus content of ≥20 mg / kg, and available potassium content of ≥180 mg / kg; (c) If the nitrogen yield response of melon is unknown and there is no soil test data, the soil nutrient level is determined according to the following conditions: low fertility melon field soil meets the following conditions: sandy soil or slightly yellow clay or loam; medium fertility melon field soil meets the following conditions: clay or loam with medium organic matter content and gray or brown; high fertility melon field soil meets the following conditions: clay or loam with high organic matter content and black; After determining the soil nutrient level according to the above steps, the nitrogen yield response coefficient corresponding to different soil nutrient levels is determined: the nitrogen yield response coefficient corresponding to the low-fertility melon field soil under flat-bed planting is 0.163, the nitrogen yield response coefficient corresponding to the medium-fertility melon field soil is 0.151, and the nitrogen yield response coefficient corresponding to the high-fertility melon field soil is 0.139; the nitrogen yield response coefficient corresponding to the low-fertility melon field soil under furrow irrigation planting is 0.199, the nitrogen yield response coefficient corresponding to the medium-fertility melon field soil is 0.168, and the nitrogen yield response coefficient corresponding to the high-fertility melon field soil is 0.109. Then, according to the formula in step (1), Nitrogen yield response = target yield × nitrogen yield response coefficient to determine the nitrogen yield response.

[0007] Step (3) determining the agronomic efficiency of nitrogen fertilizer: after obtaining the nitrogen yield reaction in step (2), the corresponding agronomic efficiency of nitrogen fertilizer is calculated according to the following formula: Agronomic efficiency of nitrogen fertilizer for melon in flat-bed planting: y = -0.0959X 2 +4.9754X-0.8821; Agronomic efficiency of nitrogen fertilizer for melon under furrow irrigation: y = -0.1554X 2 +5.02X-0.7829. Where y is the agronomic efficiency of nitrogen fertilizer, the unit of agronomic efficiency is kg / kg, X is the nitrogen yield response, the unit of nitrogen yield response is t / ha; Step (4) Determine the nitrogen fertilizer application rate: The yield response and agronomic efficiency are obtained through the above steps. According to the formula: nitrogen application rate (FN, kg N / ha) = yield response (t / ha)*1000 / agronomic efficiency (kg / kg), the nitrogen fertilizer application rate for the melon field can be obtained.

[0008] After determining the recommended application rate of nitrogen fertilizer as mentioned above, determine the base-top dressing ratio according to the growth law of melon, and apply fertilizer according to the base-top dressing ratio and the number of fertilizations.

[0009] The above-mentioned fertilizer type is single nitrogen fertilizer. When the soil in the melon field is of low fertility, 40% of the nitrogen fertilizer is applied deeply on the side as base fertilizer, and 60% of the nitrogen fertilizer is applied with water 5 times in the vine extension period, flowering period, flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 5:5:15:20:15; when the soil in the melon field is of medium fertility, 30% of the nitrogen fertilizer is applied deeply on the side as base fertilizer, and 70% of the nitrogen fertilizer is applied with water 4 times in the flowering period, flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 10:15:25:20; when the soil in the melon field is of high fertility, all of it is topdressed, applied with water 3 times in the flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 20:35:25.

[0010] If compound fertilizer is used and the melon field soil is of low fertility, the stable compound fertilizer and compound fertilizer are mixed at a ratio of 2:1 and applied sideways deeply; if the melon field soil is of medium fertility, the stable compound fertilizer and compound fertilizer are mixed at a ratio of 1:1 and applied sideways deeply; if the melon field soil is of high fertility, the stable compound fertilizer can be applied as a base fertilizer once, and the calculation formula is: Actual fertilizer application amount (kg / mu) = (FN+FP+FK) / n, Among them, FN represents the pure nutrient content of nitrogen fertilizer, FP represents the pure nutrient content of phosphorus fertilizer, FK represents the pure nutrient content of potassium fertilizer, and n represents the total nutrient content of N-P2O5-K2O (%);

[0011] If organic fertilizer is used, 30%-40% of organic fertilizer nitrogen (sheep manure) can be applied deep into the side instead of chemical fertilizer nitrogen.

[0012] When applying the above-mentioned top dressing, apply elemental nitrogen fertilizer along with water 3-5 times.

[0013] The present invention has the following advantages and beneficial effects: 1. The method for recommending nitrogen fertilizer application for melon based on yield response and agronomic efficiency of the present invention takes into account the crop rotation system, straw return to the field, residual nutrient effect of previous crop, application of organic fertilizer, atmospheric deposition, irrigation water and other sources of nutrients other than the soil itself. The recommended fertilization for melon is obtained based on the correlation between crop agronomic efficiency and yield response, and is appropriately adjusted according to the specific information of the plot and the classification of the basic nutrient supply capacity of the soil; 2. The yield response and relative yield reflect the basic nutrient supply capacity of the soil, while the agronomic efficiency reflects the fertilizer effect. There is a significant quadratic curve relationship between the yield response and the agronomic efficiency. As the yield response continues to increase, the agronomic efficiency also increases. As the yield response continues to increase, the increase in agronomic efficiency gradually decreases. Since this relationship includes different environmental conditions and soil fertility levels, the melon-specific fertilizer formulation and recommended application method of the present invention have regional characteristics and are targeted, and have a guiding role in the rational use of fertilizers; 3. The method for recommending the application of melon nitrogen fertilizer based on yield response and agronomic efficiency overcomes the blindness of farmers' habitual fertilization and the complexity and difficulty of soil testing and fertilizer matching, saves time and labor, and has strong operability. At the same time, it is more conducive to maintaining the nutrient balance of soil and crops, thereby promoting the benign circulation and utilization of nutrients, and reducing the risks of soil salinization, compaction, and continuous cropping diseases caused by excessive or unbalanced fertilization; 4. The recommended application method of melon nitrogen fertilizer based on yield response and agronomic efficiency of the present invention is based on the nutrient demand law of melon obtained by simulating a large amount of historical data, which conforms to the 4R principle, that is, selecting the right type of fertilizer, using the right amount, applying it at the right time and in the right place to meet the nutrient demand of crops and achieve synchronization of supply and demand. It has general guiding significance and strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The specific technical solution of the present invention is given by the following drawings and embodiments: Figure 1 This is the relationship diagram between melon yield response and agronomic efficiency under flat-bed planting mode; Figure 2 This is a graph showing the relationship between melon yield response and agronomic efficiency under furrow irrigation planting mode. DETAILED DESCRIPTION

[0015] The present invention is not limited by the following embodiments, and specific implementation methods can be determined based on the technical solution of the present invention and actual conditions.

[0016] This is a simple and efficient recommended method for nitrogen fertilizer application for melons, which is carried out according to the following method:

[0017] Step (1) Determine the target yield of melon: target yield (t / ha) = yield obtained in previous years or the previous year × 1.1;

[0018] Step (2) determines the nitrogen yield response: it refers to the difference in yield between the nitrogen fertilizer treatment and the nitrogen deficiency treatment: (a) If the nitrogen yield response of melon is known, then proceed directly to the solution of the following step (3); (b) If the yield response of melon nitrogen is unknown, the soil nutrient grade is determined based on the following soil test data. The soil nutrient grade classification principle is: low-fertility melon field soils have an organic matter content of ≤1.5%, available nitrogen content of ≤60 mg / kg, available phosphorus content of ≤10 mg / kg, and available potassium content of ≤100 mg / kg; medium-fertility melon field soils have an organic matter content of 1.5% to 2.5%, available nitrogen content of 60 mg / kg to 90 mg / kg, available phosphorus content of 10 mg / kg to 20 mg / kg, and available potassium content of 100 mg / kg to 180 mg / kg; high-fertility melon field soils have an organic matter content of ≥2.5%, available nitrogen content of ≥90 mg / kg, available phosphorus content of ≥20 mg / kg, and available potassium content of ≥180 mg / kg; (c) If the nitrogen yield response of melon is unknown and there is no soil test data, the soil nutrient level is determined according to the following conditions: low fertility melon field soil meets the following conditions: sandy soil or slightly yellow clay or loam; medium fertility melon field soil meets the following conditions: clay or loam with medium organic matter content and gray or brown; high fertility melon field soil meets the following conditions: clay or loam with high organic matter content and black; After determining the soil nutrient level according to the above steps, the nitrogen yield response coefficient corresponding to different soil nutrient levels is determined: the nitrogen yield response coefficient corresponding to the low-fertility melon field soil under flat-bed planting is 0.163, the nitrogen yield response coefficient corresponding to the medium-fertility melon field soil is 0.151, and the nitrogen yield response coefficient corresponding to the high-fertility melon field soil is 0.139; the nitrogen yield response coefficient corresponding to the low-fertility melon field soil under furrow irrigation planting is 0.199, the nitrogen yield response coefficient corresponding to the medium-fertility melon field soil is 0.168, and the nitrogen yield response coefficient corresponding to the high-fertility melon field soil is 0.109. Then, according to the formula in step (1), Nitrogen yield response = target yield × nitrogen yield response coefficient to determine the nitrogen yield response.

[0019] Step (3) determining the agronomic efficiency of nitrogen fertilizer: after obtaining the nitrogen yield reaction in step (2), the corresponding agronomic efficiency of nitrogen fertilizer is calculated according to the following formula: Agronomic efficiency of nitrogen fertilizer for melon in flat-bed planting: y = -0.0959X 2 +4.9754X-0.8821; Agronomic efficiency of nitrogen fertilizer for melon under furrow irrigation: y = -0.1554X 2 +5.02X-0.7829. Where y is the agronomic efficiency of nitrogen fertilizer, the unit of agronomic efficiency is kg / kg, X is the nitrogen yield response, the unit of nitrogen yield response is t / ha;

[0020] Step (4) Determine the nitrogen fertilizer application rate: The yield response and agronomic efficiency are obtained through the above steps. According to the formula: nitrogen application rate (FN, kg N / ha) = yield response (t / ha)*1000 / agronomic efficiency (kg / kg), the nitrogen fertilizer application rate for the melon field can be obtained.

[0021] After determining the recommended application rate of nitrogen fertilizer as mentioned above, determine the base-top dressing ratio according to the growth law of melon, and apply fertilizer according to the base-top dressing ratio and the number of fertilizations.

[0022] The above-mentioned fertilizer type is single nitrogen fertilizer. When the soil in the melon field is of low fertility, 40% of the nitrogen fertilizer is applied deeply on the side as base fertilizer, and 60% of the nitrogen fertilizer is applied with water 5 times in the vine extension period, flowering period, flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 5:5:15:20:15; when the soil in the melon field is of medium fertility, 30% of the nitrogen fertilizer is applied deeply on the side as base fertilizer, and 70% of the nitrogen fertilizer is applied with water 4 times in the flowering period, flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 10:15:25:20; when the soil in the melon field is of high fertility, all of it is topdressed, applied with water 3 times in the flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 20:35:25.

[0023] If compound fertilizer is used and the melon field soil is of low fertility, the stable compound fertilizer and compound fertilizer are mixed at a ratio of 2:1 and applied sideways deeply; if the melon field soil is of medium fertility, the stable compound fertilizer and compound fertilizer are mixed at a ratio of 1:1 and applied sideways deeply; if the melon field soil is of high fertility, the stable compound fertilizer can be applied as a base fertilizer once, and the calculation formula is: Actual fertilizer application amount (kg / mu) = (FN+FP+FK) / n, Among them, FN represents the pure nutrient content of nitrogen fertilizer, FP represents the pure nutrient content of phosphorus fertilizer, FK represents the pure nutrient content of potassium fertilizer, and n represents the total nutrient content of N-P2O5-K2O (%);

[0024] If organic fertilizer is used, 30%-40% of organic fertilizer nitrogen (sheep manure) can be applied deep into the side instead of chemical fertilizer nitrogen.

[0025] When applying the above-mentioned top dressing, apply elemental nitrogen fertilizer along with water 3-5 times.

[0026] The simple and efficient melon nitrogen fertilizer recommendation method disclosed in the present invention is simple to operate and can be used with or without soil testing. It can more reasonably recommend the application amount of nitrogen fertilizer to farmers, improve the utilization rate of nitrogen fertilizer, and reduce the impact of nitrogen fertilizer on the environment. Compared with the melon yield benefit obtained by melon farmers through conventional fertilization, the cotton yield benefit obtained by using the fertilization method described in the present application is significantly improved.

[0027] In step (1) of the method of the present invention, please refer to Table 1 for determining the soil nutrient level. Table 1 Soil nutrient level indicators Soil nutrient level Organic matter / % Available nitrogen / (mg / kg) Available phosphorus / (mg / kg) Available potassium / (mg / kg) Low ≤1.5 ≤60 ≤10 ≤100 middle 1.5～2.5 60～90 10～20 100～180 high ≥2.5 ≥90 ≥20 ≥180

[0028] In step (1) of the method of the present invention, the target yield (t / ha) = the yield obtained in the previous year or the previous year × 1.1, and the coefficient 1.1 is the result obtained through a large number of field tests in the early stage.

[0029] Example 1: Xizhoumi No. 25 in a flat-bed planting cultivation mode, with an average yield of 47.76t / ha last year, unknown yield response, but soil testing was done before, the test results are: organic matter 1.84%, available nitrogen 85.43mg / kg, available phosphorus 18mg / kg, available potassium 150mg / kg. According to the soil nutrient level index classification standard, the melon field soil nutrient level can be defined as medium, and the corresponding medium soil yield response coefficient is 0.151.

[0030] According to the formula: target yield = farmers' available yield * 1.1, we can get this year's target yield of 47.76t / ha * 1.1 = 52.536t / ha.

[0031] According to the formula: yield response = target yield * yield response coefficient, the yield response can be obtained as 52.536t / ha*0.151=7.933t / ha.

[0032] According to the relationship formula between yield response and agronomic efficiency: y = -0.0959X 2 +4.9754X-0.8821, the agronomic efficiency is 32.552kg / kg.

[0033] According to the formula: nitrogen application rate (FN, kg N / ha) = yield response (t / ha) / agronomic efficiency (kg / kg) × 1000, the recommended fertilizer application rate for the open potato field is 243.699 kg / ha, and the final yield is 50.25 t / ha.

[0034] Embodiment 2, a kind of Jiashi melon under furrow irrigation planting cultivation mode has an annual yield of 60.52t / ha, and the nitrogen yield response is unknown, and there is no soil test. By observing the surface properties of the soil, the melon field soil is clay, yellow. According to the estimation of soil nutrient grade, it can be determined that the soil nutrient grade of the melon field is low (low fertility melon field soil), and the nitrogen yield response coefficient corresponding to the low fertility melon field soil is 0.199.

[0035] According to the formula: target yield = yield obtained last year × 1.1, this year's target yield is 60.52 × 1.1 = 66.572 t / ha.

[0036] According to the formula: Nitrogen yield response = target yield × nitrogen yield response coefficient = 66.572 × 0.199 = 13.248 t / ha.

[0037] According to the relationship between nitrogen yield response and nitrogen fertilizer agronomic efficiency: y = -0.1554X 2 +5.02X-0.7829, the agronomic efficiency of nitrogen fertilizer is 38.448kg / kg.

[0038] According to the formula: nitrogen application rate (FN, kg N / ha) = nitrogen yield response (t / ha) × 1000 / agronomic efficiency of nitrogen fertilizer (kg / kg), the recommended nitrogen application rate for the melon field is 344.567 kg / ha, and the final yield is 62.05 t / ha.

[0039] Example 3: A type of Nasmith planted in a flat-bed cultivation mode has an average yield of 27.59 t / ha last year, and a nitrogen yield of 8 t / ha. Then the target yield this year = 27.59 × 1.1 = 30.349 t / ha.

[0040] According to the relationship between nitrogen yield response and nitrogen fertilizer agronomic efficiency: y = -0.0959X 2 +4.9754X-0.8821, the agronomic efficiency is 32.784kg / kg.

[0041] According to the formula: nitrogen application rate (FN, kg N / ha) = nitrogen yield response (t / ha) × 1000 / agronomic efficiency of nitrogen fertilizer (kg / kg), the recommended nitrogen application rate for the melon field is 244.025 kg / ha. The final yield is 30.83 t / ha.

[0042] The present invention has the following advantages and beneficial effects: 1. The method for recommending nitrogen fertilizer application for melon based on yield response and agronomic efficiency of the present invention takes into account the crop rotation system, straw return to the field, residual nutrient effect of previous crop, application of organic fertilizer, atmospheric deposition, irrigation water and other sources of nutrients other than the soil itself. The recommended fertilization for melon is obtained based on the correlation between crop agronomic efficiency and yield response, and is appropriately adjusted according to the specific information of the plot and the classification of the basic nutrient supply capacity of the soil; 2. The yield response and relative yield reflect the basic nutrient supply capacity of the soil, while the agronomic efficiency reflects the fertilizer effect. There is a significant quadratic curve relationship between the yield response and the agronomic efficiency. As the yield response continues to increase, the agronomic efficiency also increases. As the yield response continues to increase, the increase in agronomic efficiency gradually decreases. Since this relationship includes different environmental conditions and soil fertility levels, the melon-specific fertilizer formulation and recommended application method of the present invention have regional characteristics and are targeted, and have a guiding role in the rational use of fertilizers; 3. The method for recommending the application of melon nitrogen fertilizer based on yield response and agronomic efficiency overcomes the blindness of farmers' habitual fertilization and the complexity and difficulty of soil testing and fertilizer matching, saves time and labor, and has strong operability. At the same time, it is more conducive to maintaining the nutrient balance of soil and crops, thereby promoting the benign circulation and utilization of nutrients, and reducing the risks of soil salinization, compaction, and continuous cropping diseases caused by excessive or unbalanced fertilization; 4. The recommended application method of melon nitrogen fertilizer based on yield response and agronomic efficiency of the present invention is based on the nutrient demand law of melon obtained by simulating a large amount of historical data, which conforms to the 4R principle, that is, selecting the right type of fertilizer, using the right amount, applying it at the right time and in the right place to meet the nutrient demand of crops and achieve synchronization of supply and demand. It has general guiding significance and strong applicability.

[0043] The above description is only an example for clearly explaining the present invention, and is not intended to limit the implementation of the present invention. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A simple and efficient recommended method for nitrogen fertilizer application for melon, characterized in that Follow the steps below, Step (1) Determine the target yield of melon: target yield (t / ha) = yield obtained in previous years or the previous year × 1.1; Step (2) Determine the nitrogen yield response: This refers to the difference in yield between the nitrogen fertilization treatment and the nitrogen deficiency treatment: (a) If the nitrogen yield response of melon is known, then proceed directly to the solution of the following step (3); (b) If the yield response of melon nitrogen is unknown, the soil nutrient grade shall be determined based on the following soil test data. The soil nutrient grade classification principle is as follows: organic matter content ≤1.5%, available nitrogen content ≤60mg / kg, available phosphorus content ≤10mg / kg, and available potassium content ≤100mg / kg are low-fertility melon field soils; organic matter content 1.5% to 2.5%, available nitrogen content 60mg / kg to 90mg / kg, available phosphorus content 10mg / kg to 20mg / kg, and available potassium content 100mg / kg to 180mg / kg are medium-fertility melon field soils; organic matter content ≥2.5%, available nitrogen content ≥90mg / kg, available phosphorus content ≥20mg / kg, and available potassium content ≥180mg / kg are high-fertility melon field soils; (c) If the nitrogen yield response of melon is unknown and there is no soil test data, the soil nutrient level is determined according to the following conditions: low fertility melon field soil meets the following conditions: sandy soil or slightly yellow clay or loam; medium fertility melon field soil meets the following conditions: clay or loam with medium organic matter content and gray or brown; high fertility melon field soil meets the following conditions: clay or loam with high organic matter content and black; After determining the soil nutrient level according to the above steps, the nitrogen yield response coefficient corresponding to different soil nutrient levels is determined: the nitrogen yield response coefficient corresponding to low-fertility melon field soil under flat-bed planting is 0.163, the nitrogen yield response coefficient corresponding to medium-fertility melon field soil is 0.151, and the nitrogen yield response coefficient corresponding to high-fertility melon field soil is 0.139; the nitrogen yield response coefficient corresponding to low-fertility melon field soil under furrow irrigation planting is 0.199, the nitrogen yield response coefficient corresponding to medium-fertility melon field soil is 0.168, and the nitrogen yield response coefficient corresponding to high-fertility melon field soil is 0.

109. Then, according to the formula in step (1), Nitrogen yield response = target yield × nitrogen yield response coefficient to determine the nitrogen yield response; Step (3) determining the agronomic efficiency of nitrogen fertilizer: after obtaining the nitrogen yield response in step (2), the corresponding agronomic efficiency of nitrogen fertilizer is calculated according to the following formula: Agronomic efficiency of nitrogen fertilizer for melon in flat-bed planting: y=-0.0959X 2 +4.9754X-0.8821; Agronomic efficiency of nitrogen fertilizer for melon under furrow irrigation: y=-0.1554X 2 +5.02X-0.7829; Where y is the agronomic efficiency of nitrogen fertilizer, the unit of agronomic efficiency is kg / kg, X is the nitrogen yield response, the unit of nitrogen yield response is t / ha; Step (4) Determine the nitrogen fertilizer application rate: The yield response and agronomic efficiency are obtained through the above steps. According to the formula: nitrogen application rate (FN, kg N / ha) = yield response (t / ha)*1000 / agronomic efficiency (kg / kg), the nitrogen fertilizer application rate for the melon field can be obtained.

2. A simple and efficient recommended nitrogen fertilizer application method for melon according to claim 1, characterized in that: After determining the recommended application rate of nitrogen fertilizer, determine the base-top dressing ratio according to the growth pattern of melon, and apply fertilizer according to the base-top dressing ratio and the number of fertilizations.

3. A simple and efficient recommended nitrogen fertilizer application method for melon according to claim 2, characterized in that: The type of fertilizer is single nitrogen fertilizer. When the soil in the melon field is of low fertility, 40% of the nitrogen fertilizer is applied deeply on the side as base fertilizer, and 60% of the nitrogen fertilizer is applied with water 5 times in the vine extension period, flowering period, flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 5:5:15:20:15; when the soil in the melon field is of medium fertility, 30% of the nitrogen fertilizer is applied deeply on the side as base fertilizer, and 70% of the nitrogen fertilizer is applied with water 4 times in the flowering period, flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 10:15:25:20; when the soil in the melon field is of high fertility, all of it is topdressed, applied with water 3 times in the flowering and fruiting period, fruit setting period and fruit expansion period, and the application ratio is 20:35:

25.

4. A simple and efficient recommended nitrogen fertilizer application method for melon according to claim 2, characterized in that: If compound fertilizer is used and the melon field soil is of low fertility, stable compound fertilizer and compound fertilizer should be mixed at a ratio of 2:1 and applied sideways; When the soil is of medium fertility, stable compound fertilizer and compound fertilizer are mixed at a ratio of 1:1 and applied sideways and deeply; when the soil in the melon field is of high fertility, stable compound fertilizer can be applied as a base fertilizer once, and the calculation formula is: Actual fertilizer application amount (kg / mu) = (FN+FP+FK) / n, Among them, FN represents the pure nutrient content of nitrogen fertilizer, FP represents the pure nutrient content of phosphorus fertilizer, FK represents the pure nutrient content of potassium fertilizer, and n represents the total nutrient content of N-P2O5-K2O (%); If organic fertilizer is used, 30%-40% of organic fertilizer nitrogen (sheep manure) can be applied deep into the side instead of chemical fertilizer nitrogen.

5. A simple and efficient recommended nitrogen fertilizer application method for melon according to claim 2, characterized in that: When applying top dressing, apply elemental nitrogen fertilizer along with water 3-5 times.

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