Special compound fertilizer for Rubus chingii Hu and its method for saving fertilizer and increasing efficiency

Abstract

A special compound fertilizer for *Raspberry palmatum* and its fertilizer-saving and efficiency-enhancing fertilization method belong to the field of agricultural planting and fertilizer technology. The core components of the special compound fertilizer are nitrogen (N), phosphorus pentoxide (P₂O₅), and potassium oxide (K₂O), with a mass percentage of 16:6:22, and may contain borax and zinc sulfate. The fertilization method includes: soil diagnosis, fertilization plan formulation, precision fertilization, dynamic monitoring, and optimization. This invention provides a special fertilizer formula that matches the nutritional needs of *Raspberry palmatum* during its flowering and fruit-setting stages, and combines it with variable fertilization technology based on soil testing. This achieves a synergistic effect of fertilizer saving, increased yield, and improved quality by reducing the amount of chemical fertilizer used while effectively increasing the fruit yield and the content of key medicinal components of *Raspberry palmatum*.

Description

Technical Field

[0001] This invention belongs to the field of agricultural planting and fertilizer technology, specifically relating to a special fertilizer for Raspberry palmatum and its application method. Background Technology

[0002] palmate raspberry ( Rubus chingii Rubus (Hu) is a perennial medicinal plant belonging to the genus Rubus in the family Rosaceae. Its dried fruit is included in the Chinese Pharmacopoeia and has effects such as tonifying the kidneys and strengthening essence. It is an important economic crop with both medicinal and edible uses, and market demand continues to grow. In large-scale cultivation, scientific fertilization is a key management aspect to ensure its yield and quality, and fertilization measures are now widely adopted in production.

[0003] However, current cultivation of palmate raspberry mainly relies on general-purpose balanced compound fertilizers with a nitrogen-phosphorus-potassium ratio of 15-15-15, and the amount and timing of fertilization are largely determined based on traditional experience. This model has significant drawbacks: First, the general formula fails to match the specific needs of palmate raspberry for potassium and phosphorus during the flowering to fruit-setting period, especially neglecting the crucial role of potassium in fruit setting and development, which can easily lead to nutrient imbalance and flower and fruit drop. Second, empirical fertilization does not take into account the soil physicochemical characteristics of different planting areas, and cannot specifically supplement the actual lack of nutrients, resulting in low fertilizer utilization efficiency. This not only increases production costs and environmental risks, but also makes it difficult to consistently guarantee fruit yield and the content of its medicinal active ingredients (such as ellagic acid).

[0004] While existing research has covered the impact of fertilizers on fruit tree growth, a systematic solution specifically for Raspberry palmatum, which integrates soil testing data, specialized fertilizer formulations, and precise fertilization management throughout its entire growth cycle, while also considering product availability and feasibility for widespread application, remains scarce. Therefore, there is an urgent need to develop a specialized fertilizer and its accompanying application methods that can both conserve fertilizer and increase yield and quality, in order to solve the current technical challenge of low fertilizer utilization rates in the industry. Summary of the Invention

[0005] To address the technical problems in existing Raspberry cultivation, such as the reliance on general-purpose fertilizers (e.g., NPK 15-15-15) and extensive, experience-based fertilization leading to mismatches between fertilizer ratios and specific nutrient requirements, low fertilizer utilization, nutrient waste and environmental pollution, and unstable fruit yield and medicinal quality, this invention provides a specialized compound fertilizer precisely matched to the nutrient needs of Raspberry (especially during its flowering and fruit-setting stages), and a fertilizer-saving and efficiency-enhancing fertilization method based on soil diagnosis and dynamic monitoring. The aim is to achieve both stable yield increases and quality improvement in Raspberry while significantly reducing fertilizer usage. To achieve the above objectives, the present invention adopts the following technical solution: A compound fertilizer specifically for Raspberry palmata, characterized in that the mass percentages of nitrogen (N), phosphorus pentoxide (P2O5), and potassium oxide (K2O) are 16:6:22.

[0006] The aforementioned compound fertilizer for Raspberry palmatum is characterized in that it further contains borax and zinc sulfate; based on the total mass of the compound fertilizer, the content of borax is 0.3% to 0.5%, and the content of zinc sulfate is 0.2% to 0.4%.

[0007] The method for applying the special compound fertilizer to Raspberry palmatum for fertilizer saving and efficiency enhancement is characterized by the following steps: Step 1: Soil diagnosis: Collect soil samples from the target planting plot and determine its basic physicochemical properties; Step 2: Fertilization plan development: Based on the soil diagnosis results in Step 1, determine the application rate and key fertilization period of the special compound fertilizer; Step 3: Precision fertilization: Apply fertilizer in multiple applications during one or more key phenological stages of the palmate raspberry, following the plan developed in Step 2. Step 4: Dynamic monitoring and optimization: Monitor crop growth or soil nutrient dynamics during the growing season, and optimize subsequent fertilization decisions based on the monitoring results.

[0008] The specific method is as follows: During the growing season, crop growth (e.g., by measuring the relative chlorophyll content of leaves using a step-by-step PAD instrument) and / or soil nutrient dynamics are monitored. Based on the monitoring data, and combined with fruit yield and quality indicators measured after harvest (especially the content of ellagic acid and kaempferol-3-O-rutin), the fertilization effect of the year is evaluated, and the evaluation results are used as feedback information to optimize and adjust the fertilization plan for the next production cycle (e.g., fine-tuning the total application rate or the allocation ratio at different times), thereby achieving closed-loop management and continuous improvement.

[0009] The fertilization method is characterized in that, in step 1, the basic physicochemical properties include at least pH value, organic matter, alkaline nitrogen, available phosphorus, and available potassium content.

[0010] The fertilization method is characterized in that, in step 2, the total annual application rate of the special compound fertilizer is determined to be 70 kg / mu.

[0011] The fertilization method is characterized in that the key phenological periods are after pruning, before winter, and before spring budding, and the number of fertilizations per year is 3.

[0012] The fertilization method is characterized in that, in step 4, monitoring crop growth includes using a chlorophyll meter to measure the relative chlorophyll content (step PAD value) of functional leaves.

[0013] The fertilization method is characterized in that, in step 4, the basis for optimizing subsequent fertilization decisions also includes the detection results of the content of ellagic acid and kaempferol-3-O-rutin in the fruit.

[0014] Compared with the prior art, the present invention has the following significant advantages and beneficial effects: (1) The formula is highly targeted, solving the problem of nutrient imbalance from the source: The ratio of the special compound fertilizer (16-6-22) directly targets the nutritional shortcomings of the reproductive growth stage of Raspberry palmatum (high potassium requirement and key phosphorus requirement), and is supplemented with the necessary boron and zinc elements, fundamentally solving the problem of nutrient supply and demand mismatch caused by the general formula (15-15-15), laying the material foundation for high yield and quality. (2) Achieving a significant synergistic effect of fertilizer saving and yield increase: Through the precise decision of "determining yield by measuring (soil)", this method can significantly increase the yield per mu of Raspberry palmatum (especially the thorny variety) while reducing the total amount of fertilizer used by about 30% (for example, from the conventional 100 kg / mu to 70 kg / mu). The yield increase is more than 10% in the example, achieving the goal of reducing fertilizer use without reducing yield or even increasing yield, with outstanding economic and environmental benefits. (3) Effectively ensures and improves the medicinal quality of the fruit: After applying the fertilizer and method of this invention, the content of the core medicinal active ingredients (ellagic acid, kaempferol-3-O-rutin) in the fruit of *Raspberry palmatum* is stable and generally higher than that of traditional fertilization methods, ensuring that the quality of the medicinal material meets or even exceeds the standards of the Chinese Pharmacopoeia and improving the product value. (4) Forms a systematic and optimizable intelligent management solution: This invention does not provide a single fertilizer or a fixed fertilization table, but a complete technical system covering "pre-diagnosis - mid-term execution - post-feedback optimization". This system has self-learning and self-adaptive capabilities and can be dynamically adjusted according to the specific conditions of different fields and different years. It is technologically advanced, highly operable, and easy to promote and apply in large-scale planting bases. It is of great significance to promote the development of the *Raspberry palmatum* industry towards precision, greening, and high quality. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and do not constitute a limitation thereof. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0016] Example 1: Preparation of Special Compound Fertilizer Soil sampling and analysis were conducted in the main planting areas of *Raspberry palmatum*. Soil samples were collected from a depth of 0-25 cm using a five-point method. After natural drying, soil pH, organic matter content, available nitrogen, available phosphorus, and available potassium content were measured. Based on expert recommendations (conclusions regarding the high potassium and phosphorus requirements during the flowering period of *Raspberry palmatum*) and literature research (potassium promotes pollen germination and fruit development, while phosphorus enhances root absorption), and considering fertilizer availability and practical application in demonstration and promotion, the core nutrients of the fertilizer were determined to be nitrogen (N), phosphorus (P2O5), and potassium (K2O), with a ratio of NPK (16-6-22). Auxiliary nutrients included trace elements: borax (available boron content ≥11%), added at 0.3%~0.5% of the total fertilizer mass; and zinc sulfate (available zinc content ≥22%), added at 0.2%~0.4% of the total fertilizer mass.

[0017] Example 2: Fertilizer-saving and efficiency-enhancing fertilization method The following details the fertilization method and steps for using the aforementioned special compound fertilizer. It should be noted that, unless otherwise specified, in the following examples, the "percentage reduction" or "70% dosage," etc., are calculated based on the total fertilizer application of the control treatment (CK) of 100 kg / mu (see Table 1): Step 1: Soil Diagnosis: Before the start of the fertilization year, collect topsoil samples from the target field at a depth of 0-25cm using the "five-point method," mix them thoroughly, and determine their basic physicochemical properties. Required parameters include: pH value, organic matter content, available nitrogen content, available phosphorus content, and available potassium content. This step aims to quantify the soil's baseline fertility and identify nutrient limiting factors. Step 2: Fertilization plan development: Based on the soil diagnosis results in Step 1, and taking into account the variety of the planted palm-leaf raspberry (such as "thorny" or "thornless"), tree age, growth status, and other information, a precise fertilization plan is developed. Determine the total application rate: For fields with moderate soil fertility (e.g., 15-20 g / kg organic matter, 80-120 mg / kg available nitrogen), the recommended annual total application rate of the aforementioned special compound fertilizer is 70 kg / mu. This application rate is equivalent to reducing the conventional control application rate (100 kg / mu) by 30%, and is the core recommended value for achieving fertilizer saving and efficiency improvement. Determine the timing and frequency of fertilization: It is recommended to fertilize three times a year during three key phenological periods. These three periods are: after summer pruning (around June), before autumn and winter (around October), and before spring budding (around March of the following year). This arrangement aims to meet the key needs of tree recovery, nutrient storage, and spring growth. Step 3: Precision Fertilization: Following the plan established in Step 2, apply the calculated fertilizer at the designated time using conventional methods such as trenching, hole application, or broadcasting followed by shallow covering, to the main root distribution area of ​​the plant. Ensure even fertilization and combine it with irrigation according to soil moisture conditions; Step 4: Dynamic monitoring and optimization: Establish a feedback mechanism to continuously optimize fertilization effects.

[0018] Growing season monitoring: During key growth periods (such as the new shoot growth period and flowering period), the relative chlorophyll content (SPAD value) of functional leaves is randomly measured using a chlorophyll meter (SPAD meter) to qualitatively assess the nitrogen nutrition status of the plants.

[0019] Post-harvest evaluation: After the fruit is harvested, the yield is measured and samples are taken to test the content of the core medicinal components ellagic acid and kaempferol-3-O-rutin.

[0020] Solution Iteration: The dynamic SPAD values, final yield, and quality data of the current season are analyzed in conjunction with the initial soil diagnosis results and fertilization plan to evaluate the effectiveness of this fertilization. The analysis results are used as important feedback to fine-tune the total amount of fertilizer or the allocation ratio of each period in the following year, achieving closed-loop management and continuous improvement in precision. Based on the characteristics of the main nutrient components of Raspberry palmatum during the fruiting period, and combined with the dynamic changes of major nutrient elements, an application trial of the new fertilizer formulation NPK (16-6-22) in fertilizer reduction and precision fertilization is conducted.

[0021] This invention provides a fertilizer-saving and efficiency-enhancing fertilization method for Raspberry palmatum, the specific process of which can be referred to as follows: (1) Collect basic physical and chemical data of the soil in the planting field and the current status of daily fertilization management, and evaluate its health status; (2) During the fruiting period, whole plant samples were randomly collected to analyze and evaluate the biomass throughout the entire growth cycle and to study the total annual consumption of elements such as N, P, and K. (3) Based on the above experience in fertilizer application, soil physicochemical characteristics and data analysis, combined with monitoring throughout the entire growth period, adjust the fertilizer application to form an initial fertilization plan; (4) Based on the initial fertilization plan, optimize the fertilization method according to changes in fertility requirements and weather data; (5) Fertilization was carried out in the field planting area, and data such as SPAD of palm-leaved raspberry were collected in a timely manner; including the comparison area of ​​different fertilization experiments and the empirical fertilization area (CK). (6) During the fruiting period in mid-to-late May, the green fruits of Raspberry palmatum were harvested in multiple rows and locations in various districts. After being dried in a three-stage variable temperature electric heating oven, the fruits were weighed and the yield per mu in each district was calculated. (7) Determine the contents of ellagic acid and kaempferol-3-O-rutin in the dried products from each region; (8) Fine-tune the amount of fertilizer based on the trend of soil fertility change, the dynamic monitoring dataset and the weather data of the next year.

[0022] Example 4: Application Test and Results 1. Experimental Design:

[0023] 1.1 Experimental site: A Raspberry palmatum planting base in a town in Liandu District, Lishui City, Zhejiang Province was selected (the soil type was loam, and the soil pH was 6.8, organic matter content was 18g / kg, available nitrogen was 95mg / kg, available phosphorus was 16mg / kg, and available potassium was 98mg / kg, according to the five-point sampling method). 1.2 Experimental Materials: The tested Raspberry palmatum varieties were "Variety A" (thorny) and "Variety B" (thornless), with a tree age of 5 years. 300 healthy, disease-free, and uniformly growing plants were selected and divided into 5 groups of 60 plants each. The experimental group (freshly formulated fertilizer NPK (16-6-22)) consisted of 4 experimental blocks: 100%, 70%, 50%, and 0%; the control group (general fertilizer NPK (15-15-15), CK). 1.3 Fertilization plan: CK is the base's empirical fertilization, that is, applying a total of about 200 kg / mu of general compound fertilizer 5 times a year; the 3 experimental blocks apply new compound fertilizer in reduced amounts, changing to 3 times a year, with the fertilizer amount being 100%, 70% and 30% of CK, and another experimental block does not apply compound fertilizer; the specific fertilization time and amount are shown in Table 1. 1.4 Experimental period: The amount of compound fertilizer applied was from the harvest of palm-leaf raspberry to the fruiting period of the following year, which is the entire growth cycle; from the end of the fruiting period of the current year to the late pruning period (early June) to the fruiting period of the following year (late May), other field management (irrigation, weeding, and pest and disease control) remained consistent.

[0024] Table 1. Specific Fertilization Experiment Design for Raspberries

[0025] 2. Detection Indicators and Methods 2.1 Growth indicators: Leaf chlorophyll content (measured using a SPAD instrument, with the average value taken from 10 functional leaves selected from each plant). 2.2 Fruit yield During the fruit harvesting period (late May), 10 plants were randomly selected, and the green and yellow fruits of each plant were collected. After drying in a three-stage variable temperature electric heating oven, the fruits were weighed and the yield per mu (unit of land area) was calculated. The yield per mu was then converted (yield per mu = yield per plant × 250 plants).

[0026] 2.3 Fruit quality The dried green and yellow fruits were sent to a local third-party drug testing institution to determine the content of ellagic acid and kaempferol-3-O-rutin according to the technical methods of the Chinese Pharmacopoeia (2020 edition).

[0027] 3. Test Results 3.1 Comparison of growth indicators: For "Variety A", 70% new fertilizer was the optimal concentration. The fertilization gradient effect was ranked as follows: 70% new fertilizer (57.92) > 50% new fertilizer (57.84) > 0% new fertilizer (55.18) > 100% new fertilizer (53.79). Key differences (LSD test): 70% new fertilizer was significantly higher than 100% new fertilizer (difference = 4.13, P = 0.026), indicating that full fertilization had an "inhibitory effect" on Variety A. Compared with the control (55.14), 70% new fertilizer was higher, while 100% and 50% new fertilizer were lower, suggesting that a 70% reduction in the amount of new fertilizer was more suitable for Variety A.

[0028] For "Variety B", 100% fresh fertilizer was the best. The fertilization gradient effect was ranked as follows: 100% fresh fertilizer (57.42) > 70% fresh fertilizer (56.04) > 0% fresh fertilizer (54.48) > 50% fresh fertilizer (54.01). Key differences (LSD test): Although 100% fresh fertilizer did not show significant differences compared to other gradients, it had the highest average value and the best stability (smallest standard deviation = 3.94); 50% fresh fertilizer had the lowest average value, 3.41 lower than 100%, close to a significant level (P = 0.065), indicating that Variety B is sensitive to fertilizer reduction; compared to the control (55.14), 100% and 70% fresh fertilizer were higher (no significant difference), while 50% and 0% fresh fertilizer were lower, indicating that Variety B requires more sufficient fertilization.

[0029] Table 2. Effects of different fertilization methods on SPAD values ​​of Raspberry leaves. deal with Variety A Variety B 100% (Patented Formula) 53.79±1.754b 57.07±0.504a 70% (patented formula) 57.92±1.593ab 56.04±1.072a 50% (patented formula) 55.18±0.975ab 54.01±1.449a 0% (Patented Formula) 58.64±0.989a 54.48±1.611a CK100% Traditional Formula 55.14±1.194a 55.14±1.194a 3.2 Comparison of Fruit Yield For the yield performance of variety A per plant The highest yield treatment: Under the 70% (patented formula) treatment, the yield per plant reached 315.328g, which was the highest value among all treatments and significantly higher than other groups.

[0030] Production volume ranking: 70% (patented formula) > 100% (patented formula) (276.096g) > CK100% Traditional formula (266.488g) > 50% (patented formula) (263.872g) > 0% (patented formula) (241.088g).

[0031] Variety A exhibited the strongest fruiting capacity per plant when the amount of fertilizer applied according to the patent formula was reduced by 30%; the yield per plant was the lowest when no fertilizer was applied (0%), which was 23.6% lower than the optimal treatment.

[0032] Table 3. Effects of different fertilization methods on the yield of Raspberry Palmarosa (Variety A) deal with Variety A single plant (g) Yield per mu (kg) for variety A 100% (Patented Formula) 276.096 69.024 70% (patented formula) 315.328 78.832 50% (patented formula) 263.872 65.968 0% (Patented Formula) 241.088 60.272 CK100% Traditional Formula 266.488 66.622

[0033] For the yield performance of variety B per plant The highest yield treatment: Under the 70% (patented formula) treatment, the yield per plant was 290.032g, which is also the highest value among all treatments for this variety.

[0034] Production volume ranking: 70% (patented formula) > 50% (patented formula) (281.2g) > 100% (patented formula) (275.664g) > CK100% Traditional Formula (260.25g) > 0% (patented formula) (254.736g).

[0035] Variety B achieved the optimal yield per plant when the amount of fertilizer applied according to the patent formula was reduced by 30%; the yield per plant in the 50% patent formula treatment was close to the optimal level and higher than that in the 100% patent formula treatment.

[0036] 70% (patented formula) is the optimal fertilization treatment for both varieties, with the highest yield per plant and yield per acre, and can be used as a basic recommended scheme.

[0037] Table 4. Effects of different fertilization methods on the yield of Raspberry Palmarosa (Variety B) deal with Variety B single plant (g) Yield per mu (kg) for Variety B 100% (Patented Formula) 275.664 68.916 70% (patented formula) 290.032 72.508 50% (patented formula) 281.2 70.300 0% (Patented Formula) 254.736 63.684 CK100% Traditional Formula 260.25 65.063 3.3 Comparison of Fruit Quality This experiment used two raspberry varieties, A and B, as materials, with one control group and four fertilization treatments (treatments 1-4) in each variety. The contents of two core active ingredients, ellagic acid (pharmacopoeia standard ≥0.2%) and kaempferol-3-O-rutin (pharmacopoeia standard ≥0.03%), were detected. All treatment data met the pharmacopoeia quality standards, and there were no unqualified samples.

[0038] For Variety A: Fertilization treatments significantly increased the accumulation of active ingredients. 1) Ellagic acid content: The control was 0.21%, slightly higher than the pharmacopoeia standard, which is the basic content level for Variety A. Fertilization treatments: Treatment 1 (0.24%), Treatment 2 (0.26%), Treatment 3 (0.25%), Treatment 4 (0.22%), all of which were higher than the control. Among them, Treatment 2 had the highest ellagic acid content (0.26%), an increase of 23.8% compared to the control; Treatment 3 and Treatment 1 were next, and Treatment 4 had the smallest increase; 2) Kaempferol-3-O-rutin content: The control was 0.03%, which just met the pharmacopoeia standard, which is the basic content for Variety A. Fertilization treatments: Treatment 1 (0.04%), Treatment 2 (0.04%), Treatment 3 (0.04%), Treatment 4 (0.05%), all of which were higher than the control. Among them, treatment 4 had the highest content (0.05%), which was 66.7% higher than the control; treatments 1-3 were all stable at 0.04%.

[0039] For variety B: The content of active ingredients is stable, and the fertilization effect is weaker than that of variety A. 1) Ellagic acid content: The control is 0.20%, which just meets the pharmacopoeia standard. Fertilization treatments: Treatment 1 (0.21%), Treatment 2 (0.20%), Treatment 3 (0.20%), Treatment 4 (0.21%). Only Treatments 1 and 4 are slightly higher than the control, while Treatments 2 and 3 are the same as the control. Fertilization has no significant effect on increasing ellagic acid content in variety B, and the overall content remains stable at 0.20%-0.21%; 2) Kaempferol-3-O-rutin content: Control: 0.04%, exceeding the pharmacopoeia standard. Fertilization treatments: Treatment 1 (0.06%), Treatment 2 (0.04%), Treatment 3 (0.04%), Treatment 4 (0.04%). Only Treatment 1 shows a slight increase, while the other treatments remain stable at 0.04%, but still meet the standard.

[0040] Table 5. Effects of fertilization experiments on the content of effective ingredients in two palmate raspberry varieties. Experimental treatment (Variety A) Ellagic acid (%) Kaempferol-3-O-rutin (%) Experimental treatment (Variety B) Ellagic acid (%) Kaempferol-3-O-rutin (%) Comparison with CK 0.21 0.03 Comparison with CK 0.20 0.05 Process 1 0.24 0.04 Process 1 0.21 0.06 Process 2 0.26 0.04 Process 2 0.20 0.04 Process 3 0.25 0.04 Process 3 0.20 0.04 Process 4 0.22 0.05 Process 4 0.21 0.04 Example 5: Application effects at different bases

[0041] Base 1: At a *Raspberry palmatum* planting base in Wanshan Township, Qingtian County, Lishui City, 70% newly formulated fertilizer was selected as the main compound fertilizer, and the above-mentioned fertilization method was applied. The planted raspberry is a thorny variety. The base area is more than 120 mu (approximately 8 hectares), at an altitude of 420m-450m. The above-mentioned fertilization method was applied to 10 mu (approximately 1.65 hectares). 15 raspberry plants were randomly selected from the experimental plot and the nearby control planting area. The average yield of green and yellow dried fruit per plant was 0.25 kg and 0.23 kg, respectively. Based on 250 plants / mu (approximately 16.7 hectares), the yield per mu (approximately 0.067 hectares) was 52.5 kg and 47.5 kg, respectively. After testing, the contents of ellagic acid and kaempferol-3-O-rutin were 0.24% and 0.22%, and 0.05% and 0.04%, respectively, all of which met the national pharmacopoeia standards.

[0042] Base Two: At a *Raspberry palmatum* planting base in Yaxi Town, Liandu District, Lishui City, 70% newly formulated fertilizer was selected as the main compound fertilizer, and the above fertilization method was applied. The base area is over 200 mu, with an altitude of 250m-260m. The above fertilization method was applied to 10 mu. 15 raspberry plants were randomly selected from the experimental plot and the nearby control planting area. The average yield of green and yellow fruits and dried fruits per plant was 0.21kg and 0.19kg, respectively. Based on 250 plants / mu, the yield per mu was 62.5kg and 57.5kg, respectively. The contents of ellagic acid and kaempferol-3-O-rutin were tested to be 0.23% and 0.22%, and 0.04% and 0.04%, respectively, all of which met the national pharmacopoeia standards.

[0043] Base 3: At a *Raspberry palmatum* planting base in Chengzhao Township, Jingning She Autonomous County, Lishui City, 70% newly formulated fertilizer was selected as the main compound fertilizer, and the above fertilization method was applied. The base area is over 50 mu (approximately 3.3 hectares), with an altitude of 350m-400m. The above fertilization method was applied to 10 mu (approximately 0.67 hectares). Fifteen *Raspberry palmatum* plants were randomly selected from the experimental plot and a nearby control planting area. The average yield per plant was 0.17 kg of green and yellow fruit and 0.16 kg of dried fruit, respectively. Based on 250 plants / mu (approximately 16.7 hectares), the yield per mu (approximately 0.067 hectares) was 42.5 kg and 40.0 kg, respectively. Testing showed that the contents of ellagic acid and kaempferol-3-O-rutin were 0.24% and 0.23%, and 0.05% and 0.04%, respectively, all meeting the national pharmacopoeia standards.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a specific fertilization program tailored to the nutritional needs of *Raspberry palmatum* from flowering to fruit setting. It establishes a new, nutritionally balanced, and targeted fertilizer formulation with a core NPK ratio. Simultaneously, a full-cycle fertilizer reduction trial was conducted on two new *Raspberry palmatum* varieties to ensure a significant reduction in fertilizer application (30%) while effectively improving fertilizer utilization and ultimately increasing *Raspberry palmatum* yield. The readily available core fertilizer formulation, combined with its practical application in demonstration and promotion, demonstrates broad adaptability and high promotional value. This is of great significance for improving the quality and efficiency of the *Raspberry palmatum* cultivation industry.

Claims

1. A compound fertilizer specifically for Raspberry Palmata, characterized in that, The mass percentages of nitrogen (N), phosphorus pentoxide (P2O5), and potassium oxide (K2O) are 16:6:

22.

2. The raspberry-specific compound fertilizer according to claim 1, characterized by It also contains borax and zinc sulfate; based on the total mass of the compound fertilizer, the content of borax is 0.3% to 0.5%, and the content of zinc sulfate is 0.2% to 0.4%.

3. A method for increasing the effect of fertilization by using the special compound fertilizer according to claim 1 or 2, characterized in that, Includes the following steps: Step 1: Soil diagnosis: Collect soil samples from the target planting plot and determine its basic physicochemical properties; Step 2: Fertilization plan development: Based on the soil diagnosis results in Step 1, determine the application rate and key fertilization period of the special compound fertilizer; Step 3: Precision fertilization: Apply fertilizer in multiple applications during one or more key phenological stages of the palmate raspberry, following the plan developed in Step 2. Step 4: Dynamic monitoring and optimization: Monitor crop growth or soil nutrient dynamics during the growing season, and optimize subsequent fertilization decisions based on the monitoring results.

4. The method of applying a fertilizer according to claim 3, wherein, In step 1, the basic physicochemical properties include at least pH value, organic matter, alkaline nitrogen, available phosphorus, and available potassium content.

5. The method of applying a fertilizer according to claim 3, wherein, In step 2, the total annual application rate of the special compound fertilizer is determined to be 70 kg / mu.

6. The method of applying a fertilizer according to claim 3, wherein, The key phenological periods are after pruning, before winter, and before spring budding, and the number of fertilizations per year is 3.

7. The method of applying a fertilizer according to claim 3, wherein, In step 4, monitoring crop growth includes using a chlorophyll meter to measure the relative chlorophyll content (SPAD value) of functional leaves.

8. The method of applying a fertilizer according to claim 3, wherein, In step 4, the basis for optimizing subsequent fertilization decisions also includes the detection results of the content of ellagic acid and kaempferol-3-O-rutin in the fruit.

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