Grape continuous cropping resistant planting method

Abstract

The invention relates to the technical field of fruit tree cultivation, in particular to a grape continuous cropping resistant planting method, and aims to solve the problems of dead seedlings, dead seedlings, low survival rate, vigorous growth vigor and quality reduction in grape continuous cropping planting. The method comprises three core links of old tree trunk-cutting crown-controlling and toxin-expelling-inhibiting, root domain limiting microenvironment ecological improvement and limited domain precise staged water and fertilizer management, wherein before field planting, trunk-cutting crown-controlling is conducted on old trees, allelochemical release is inhibited, and removing is conducted after leaves fall in autumn; digging holes among the old trees along the original planting rows, placing PVC (polyvinyl chloride) pipes to form a confinement structure, and backfilling ecological nutrient soil; field planting is conducted after new seedlings are pretreated, and water and fertilizer are only dripped within the limited range. The scheme is tested for 3 years, and results show that the planting survival rate of the new seedlings reaches 95% or above, the dead seedling rate and the dead seedling rate are greatly reduced, the new seedlings grow robustly, and the later fruiting rate and the fruit quality are stable. The method is easy and convenient to operate, controllable in cost and suitable for large-scale production, continuous cropping obstacles can be eliminated from the source, and high quality and high efficiency of grape continuous cropping planting are achieved.

Description

Technical Field

[0001] This invention relates to the field of fruit tree cultivation technology, specifically to a method for grape cultivation that resists continuous cropping. Background Technology

[0002] Replanting, also known as continuous cropping, refers to the practice of planting the same family or species of crop on the same land consecutively. Replanting obstacles are comprehensive soil problems caused by continuous cropping, including stunted crop growth and development, frequent pests and diseases, and reduced yield and quality. The root causes mainly include soil microecological imbalance, with the proliferation of harmful pathogens and a sharp decline in the proportion of beneficial microorganisms; soil nutrient imbalance, with excessive consumption of micronutrients preferred by crops and the inability to replenish them in time; continuous accumulation of allelochemicals secreted by roots, which have a toxic effect on the roots of subsequent crops; and long-term continuous cropping can also lead to the deterioration of soil physical and chemical properties, such as compaction, acidification, and salinization. The combination of these multiple factors ultimately results in weak crop growth and reduced stress resistance.

[0003] Grapes, as a perennial vine, are an important economic forestry and fruit crop in my country. With the continuous upgrading of consumer demand for grape quality and varieties, the replacement cycle of new grape varieties has shortened significantly, and the industry's need for variety iteration is becoming increasingly urgent. However, grape cultivation is strictly constrained by land use, vineyard planning, and supporting facilities. Abandoning existing vineyards and relocating to new sites not only wastes land resources but also incurs huge costs for vineyard reconstruction, facility upgrades, and labor input, resulting in significant economic losses. Therefore, updating varieties on the basis of existing vineyards has become the most economical and feasible option for the grape industry. However, when updating varieties in existing vineyards, directly replanting new grape varieties after removing the original fruit trees can easily lead to severe replanting obstacles. Specifically, this manifests as frequent stunted and dead seedlings, a significant reduction in seedling survival rates, weak growth in mature plants, fewer shoots, and slow leaf development. Later, it can also lead to low fruit set, uneven fruit size, and decreased sugar content and flavor, severely restricting the cultivation benefits of new grape varieties and becoming a core pain point in the industry's variety replacement process.

[0004] To alleviate the replanting problem in grapevines, various coping mechanisms have been developed in existing technologies. Among them, microbial inoculants have become a widely used method due to their ease of operation and environmental friendliness, and related technologies are constantly emerging. For example, CN120843303A proposes the application of a composite microbial inoculant in resisting replanting stress. Its active ingredients are Trichoderma harzianum, Pseudomonas aeruginosa, and a base carrier containing bentonite, humic acid, and biochar, as well as synergistic components such as porous starch microspheres and chitosan oligosaccharides, and soil-adaptive components such as oyster shell powder or earthworm castings granules. CN118562654A provides a multifunctional anti-replanting microbial inoculant that can decompose soil residues. CN117778028A has also developed a microbial inoculant with both anti-replanting and soil improvement effects and disclosed its preparation process. However, such microbial agents can only alleviate the harm of continuous cropping by regulating the soil microecology and inhibiting some harmful pathogens. They cannot fundamentally solve problems such as soil nutrient imbalance, accumulation of allelopathic substances, and deterioration of physicochemical properties, and are difficult to completely eliminate the obstacles of continuous cropping. On the other hand, physical methods such as soil replacement and improvement can fundamentally improve the planting substrate, but they are difficult to operate, labor-intensive, and require a lot of manpower and resources. Furthermore, large-scale soil replacement can easily damage the original soil aggregate structure, aggravate soil compaction, and may also cause secondary imbalance of the soil microbial community. Therefore, they are not feasible for large-scale operation in actual grape production.

[0005] In summary, existing methods for resisting continuous cropping have obvious technical defects and cannot meet the needs of efficient, thorough, and easy-to-operate resistance to continuous cropping cultivation in the grape industry's variety renewal and upgrading. Developing a resistance to continuous cropping cultivation technology that can fundamentally solve the grape continuous cropping obstacle, is suitable for the renewal and transformation of existing vineyards, and is easy to operate, cost-controllable, and effective has become a key technical problem that the grape industry urgently needs to overcome. Summary of the Invention

[0006] (a) Technical problems to be solved In view of the above-mentioned shortcomings and deficiencies of the existing technology, the present invention provides a method for grape replanting resistance, which combines the two aspects of controlling the crown of the large tree to suppress detoxification and improving the micro-environment ecology of the root zone of the new seedlings for planting. It solves the technical problems of stunted seedlings, dead seedlings, low survival rate, weak growth and reduced quality in grape replanting.

[0007] (II) Technical Solution In a first aspect, the present invention provides a method for resisting the harm of continuous cropping in grape cultivation, which includes: before planting new grape seedlings, performing trunk cutting and crown control treatment on the old trees to be replaced in the vineyard to inhibit and detoxify; constructing root zone restricted planting holes between the old trees in the original planting row and backfilling them with ecological nutrient soil; planting the pretreated new grape seedlings in the root zone restricted planting holes; and only within the root zone restricted area, performing staged drip irrigation and fertilizer management on the planted new grape seedlings. The trunk-cutting and crown-controlling detoxification treatment includes: severely cutting off old trees to retain the main trunk, selecting a single lower new shoot after budding to cultivate and pinching the new shoot and lateral shoots to control their growth, and only watering to maintain the tree's survival without fertilizing after cutting off until the autumn leaves fall (ensuring its survival but not its vigorous growth), and removing old trees after the autumn leaves fall. The construction of the root zone restricted planting pit includes: excavating planting pits of suitable size between old trees, placing thin-walled round plastic tubes matching the planting pits to form a restricted structure, backfilling the restricted structure with ecological nutrient soil and compacting it; the ecological nutrient soil is made by mixing fermentation products with the topsoil between the rows of vineyards in a certain proportion, the fermentation products are made by mixing edible mushroom residue, livestock and poultry manure and decomposed seeds in a mass ratio of (5-6):(3-4):(1-2) to form a fermentation substrate, which is obtained by aerobic fermentation with compound bacterial liquid, drying and pulverizing; the compound bacterial liquid is made by compounding Bacillus, Trichoderma, EM bacteria and yeast, adding sugar source and water, and fermenting under mesophilic conditions.

[0008] According to a preferred embodiment of the present invention, the pretreatment of the grape seedlings includes: soaking in clean water, root pruning, and main stem bud pruning; the staged drip irrigation and fertilization management adjusts the type and frequency of water and fertilizer according to the growth cycle of the grape seedlings.

[0009] According to a preferred embodiment of the present invention, the pretreatment of the new grape seedlings is specifically as follows: soaking in clean water for 12-24 hours, pruning the roots to retain a length of 10-12cm, and pruning the main stem to retain 2-3 plump buds; immediately after planting, thoroughly watering the root-restricted planting hole.

[0010] According to a preferred embodiment of the present invention, the old tree pruning operation is carried out 1-2 days before the planting of new grape seedlings, and the height of the main trunk retained after pruning is 30-60cm, preferably 40-50cm.

[0011] According to a preferred embodiment of the present invention, the new shoots are first pinched when they have 5-8 leaves, and the lateral shoots are pinched every 2-4 leaves. Preferably, the new shoots are first pinched when they have 6-7 leaves, and the lateral shoots are pinched every 2-3 leaves.

[0012] According to a preferred embodiment of the present invention, the diameter and depth of the planting hole are both 30-50 cm, and the thin-walled plastic tube is a PE pipe, PV pipe, PVC pipe, or corrugated pipe, the diameter and height of which are adapted to the planting hole; preferably, the diameter and depth of the planting hole are both 40 cm, and the thin-walled plastic tube is a PVC pipe. The thin-walled plastic tube needs to be removed in autumn to avoid restricting the further growth of the grape seedlings.

[0013] According to a preferred embodiment of the present invention, in the fermentation substrate, the edible fungus residue is mushroom residue, the livestock and poultry manure is sheep manure, and the decomposed seed raw material is cooked soybeans.

[0014] According to a preferred embodiment of the present invention, the raw materials of the compound bacterial solution are as follows: 35 parts Bacillus, 4-6 parts Trichoderma, 3-5 parts EM bacteria, 2-3 parts yeast, 20-30 parts sugar source, and 40-60 parts water; the medium temperature condition is 25-38℃, and the culture and fermentation time is 7-10 days.

[0015] According to a preferred embodiment of the present invention, the Bacillus is Bacillus subtilis, the Trichoderma is Trichoderma harzianum, the sugar source is brown sugar, and the culture and fermentation temperature is 28-35℃.

[0016] According to a preferred embodiment of the present invention, in the ecological nutrient soil, the mixing mass ratio of the fermentation product to the 0-20cm topsoil between the rows of the vineyard is (4-5):(5-6).

[0017] According to a preferred embodiment of the present invention, the staged drip irrigation and fertilization management specifically includes: drip irrigation with biostimulants 7-10 days after planting; drip irrigation with clean water without fertilization until the seedlings have 7-8 leaves; and alternating drip irrigation with nitrogen fertilizer and balanced fertilizer after the seedlings have grown their second tendrils, with each drip irrigation interval of 7-10 days.

[0018] According to a preferred embodiment of the present invention, the biostimulant is potassium humate derived from minerals or seaweed extract, with an application rate of 1-2 kg of potassium humate or 0.8-1 kg of seaweed extract per mu; the nitrogen fertilizer is urea, with an application rate of 10-15 kg per mu; and the balanced fertilizer is a compound fertilizer with equal proportions of nitrogen, phosphorus, and potassium, with an application rate of 10-15 kg per mu.

[0019] According to a preferred embodiment of the present invention, the nitrogen, phosphorus and potassium compound fertilizer is a compound fertilizer with a nitrogen, phosphorus and potassium mass ratio of 1:1:1.

[0020] (III) Beneficial Effects This invention addresses the replanting problems associated with continuous grape cultivation. It employs a synergistic approach, combining trunk cutting to control canopy growth and suppress toxin release, root zone microenvironmental improvement, and precise, phased water and fertilizer management within a defined area. This multi-dimensional system, encompassing source control, localized improvement, and plant cultivation, effectively solves the industry's pain points in continuous grape cultivation, such as stunted seedlings, seedling death, low survival rates, weak growth, and declining quality. Compared to existing replanting resistance methods, it offers the following significant technical advantages: 1. Significantly reduces the impact of continuous cropping toxicity and significantly improves the survival rate of new seedlings: By cutting off the trunk and controlling the crown of old vines, the synthesis and release of allelochemicals (secondary metabolites produced by the metabolism and secretion / decomposition of the roots, plant debris, and above-ground parts of old grapevines, which can have a toxic effect on subsequent grape seedlings of the same species / family; the continuous accumulation of these substances in the soil is one of the core causes of continuous cropping obstacles in grapes, mainly some phenols, phenolic acids, and flavonoids) are reduced from the source. This also prevents sudden pollution from harmful substances caused by the rotting of old vine roots. Combined with the physical isolation effect of root zone restriction, the roots of new seedlings are kept away from the toxicity of the surrounding soil deteriorated by continuous cropping, significantly reducing the probability of stunted and dead seedlings, and significantly improving the survival rate of new seedlings. At the same time, controlling fertilizer and water ensures survival but not excessive growth, which can effectively avoid the rotting of old vine roots and the generation of a large number of broken roots during the uprooting of large vines.

[0021] 2. Reconstructing a healthy root zone micro-ecology and improving the root growth environment: The ecological nutrient soil backfilled in the root zone is fermented and improved by beneficial compound microbial agents, which quickly builds a dominant root zone microbial community dominated by beneficial bacteria. This effectively inhibits the reproduction of harmful pathogens in the continuously cropped soil, while improving the root zone soil structure and supplementing balanced slow-release nutrients. This solves the problems of micro-ecological imbalance, nutrient depletion, compaction and acidification in continuously cropped soil, creating a loose, fertile and clean local micro-environment for the growth of new seedling roots, and promoting the healthy germination and extension of roots.

[0022] 3. Targeted cultivation of robust plants to enhance seedlings' resistance to continuous cropping stress: Based on the phased and limited precise water and fertilizer management of grape seedlings' growth cycle, water and fertilizer are delivered directly to the root absorption zone and are highly matched with the physiological needs of seedlings at different growth stages. This not only promotes rapid seedling establishment and root development, but also avoids water and fertilizer waste and root burn. It cultivates a robust root and crown system, significantly enhancing the grape seedlings' resistance to continuous cropping stress and solving the problems of weak seedling growth and slow shoot and leaf development in continuous cropping.

[0023] 4. Ensure the growth and development of grapevines and fruit quality, and improve planting benefits: The robust root and crown system lays a solid foundation for the later flower bud differentiation, fruit setting and fruit development of grapes. It effectively solves the quality problems such as low fruit setting rate, uneven fruit size and reduced sugar content and flavor in continuous cropping, ensuring the robust growth of grapevines and stable fruit quality throughout the entire process, and significantly improving the economic benefits of continuous cropping of grapes.

[0024] 5. The process is simple to operate and the cost is controllable, making it suitable for the actual needs of large-scale production: This invention is implemented based on the existing vineyard planting conditions, without abandoning the original land and facilities, thus avoiding the waste of manpower, material resources and financial resources in rebuilding the vineyard; the root zone is limited to local soil improvement, which is easier to operate and less labor-intensive than replacing and improving the soil and applying microbial agents throughout the entire area. Moreover, water and fertilizer are applied using a limited drip irrigation method, which greatly improves the utilization rate of water and fertilizer and reduces planting costs. At the same time, there are no special equipment requirements throughout the process, the process is simple and easy to promote, and it is fully suitable for the actual needs of large-scale and standardized production in the grape industry.

[0025] 6. Balancing soil protection and ecological planting to achieve sustainable development: This invention improves the root zone soil through biological agents and organic nutrient soil enrichment, avoiding the damage to the soil caused by strong acids and alkalis. At the same time, the limited water and fertilizer management reduces the loss and pollution of water and fertilizer to the surrounding soil. While breaking the obstacle of continuous cropping, it achieves the protection and enrichment of vineyard soil, which is in line with the concept of ecological planting and conducive to the sustainable development of the grape planting industry. Attached Figure Description

[0026] Figure 1 A schematic diagram illustrating the operation of planting seedlings to improve the ecological environment of the root zone. Detailed Implementation

[0027] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] This invention provides a method for resisting the damage caused by continuous cropping of grapes, comprising two measures: Measure 1: Cutting the trunk of large trees to control the crown and inhibit toxin release: One to two days before transplanting the seedlings, do not remove the mature trees of the variety to be replaced; instead, prune the main trunk back to 40-50cm. After new shoots sprout from the main trunk, select one shoot near the bottom to cultivate, and remove all other shoots. Pinch off the tips of the new shoots when they have 6-7 leaves. Subsequently, pinch off the tips of the lateral shoots every 2-3 leaves to control their growth. Do not fertilize the old trees, only water them sparingly, ensuring that the trees remain viable but do not grow excessively. Finally, after leaf fall in the autumn of the same year, completely uproot the mature trees.

[0029] Measure 2: Improving the microenvironment and ecology of seedling root zone during planting: a. Along the existing planting row, dig planting holes between the existing two trees. The planting holes should be 40cm in diameter and 40cm deep (see...). Figure 1 (As shown).

[0030] b. Place a thin-walled round pipe with a diameter of 40cm and a height of 40cm into the planting hole. The pipe material includes, but is not limited to, PE pipe, PV pipe, PVC pipe, corrugated pipe, etc. As a preferred choice, PVC pipe is selected to form a confined planting hole.

[0031] c. Backfill the planting hole with topsoil and ecological nutrient soil, water it to settle it, then level it and prepare for planting.

[0032] The method for preparing the ecological nutrient soil is as follows: ① Mix mushroom residue, sheep manure, and cooked soybeans in a mass ratio of (5-6):(3-4):(1-2) to obtain a fermentation substrate.

[0033] ② Add 3-5 parts of Bacillus subtilis, 4-6 parts of Trichoderma harzianum, 3-5 parts of EM bacteria, 2-3 parts of yeast, 20-30 parts of brown sugar, and 40-60 parts of water, and culture and ferment at 28-35℃ for 7-10 days to obtain bacterial solution.

[0034] ③ Add the bacterial solution obtained in step ② to the fermentation substrate obtained in step ①, and perform aerobic fermentation to obtain the initial fermentation product.

[0035] ④ The initial fermentation product obtained in step ③ is dried and crushed to obtain the fermentation product.

[0036] ⑤ Mix 4-5 parts by weight of the fermentation product obtained in step ④ with 5-6 parts by weight of the topsoil between rows (0-20cm) to obtain ecological nutrient soil.

[0037] d. Before planting, soak the seedlings in clean water for 12-24 hours, trim the roots to a length of 10-12cm, and cut the main stem to leave 2-3 plump buds.

[0038] e. Immediately after planting, thoroughly water the planting hole with clean water.

[0039] f. Water and fertilizer management: Drip irrigation is used for watering and fertilization, and watering and fertilization are only carried out within the restricted planting holes. After planting, 7-10 days later, drip 1-2 kg of mineral-derived potassium humate or 0.8-1 kg of seaweed extract per mu (667 square meters). Before the seedlings have 7-8 leaves, drip water only, do not drip fertilizer. After the second tendril appears, alternate between 10-15 kg of urea and 10-15 kg of balanced fertilizer, drip irrigating once every 7-10 days.

[0040] This invention analyzes the scientific basis and technical effects of a grape replanting resistance method. It addresses four core causes of grape replanting obstacles: soil microecological imbalance, allelochemical accumulation, soil nutrient depletion, and deterioration of the root growth environment. Through the synergistic effect of three technical modules—trunk cutting and canopy control to suppress toxin release, root zone microenvironmental ecological improvement, and precise water and fertilizer management within a defined area—it forms a closed loop against replanting obstacles from three dimensions: reducing allelochemical release at the source, locally reconstructing a healthy root zone ecology, and targeted cultivation of robust new seedling roots. The mechanisms of action of each technical link are interconnected and progressively enhanced, conforming to both the formation patterns of grape replanting obstacles and the scientific principles of grape root growth and soil ecological regulation. Ultimately, it achieves the technical effect of moving from "alleviating the harm of replanting" to "eliminating the replanting obstacle." The following is an analysis of the invention's solution. First, the practice of cutting off the trunk and controlling the crown of old grapevines to suppress detoxification can block the continuous release of allelochemicals and harmful substances at the source, cutting off the source of substances causing continuous cropping obstacles. The roots of old grapevines continuously secrete allelochemicals such as phenols, phenolic acids, and terpenes. Furthermore, as the vine ages, root decay and decomposition of plant debris release even more toxic and harmful substances. The accumulation of these substances in the soil is one of the core causes of continuous cropping obstacles. At the same time, the vigorous growth of old vines competes with new seedlings for soil nutrients, exacerbating the weakness of new seedling growth. This invention uses a dual approach of morphological and physiological regulation to reduce the release of toxic and harmful substances at the source through trunk cutting and crown control of old vines. Specifically, it includes: First, trunk pruning and crown control inhibit the tree's physiological activity and reduce the synthesis and secretion of allelochemicals in the roots. Older trees are heavily pruned back to 30-60cm, significantly reducing the tree's photosynthetic area. After bud break, only one lower shoot is selected and its growth is gradually controlled by pinching. This ensures that the tree's photosynthetic products are only sufficient for its own survival and cannot transport excess nutrients to the roots. Root physiological activity is significantly inhibited, and the synthesis and secretion of allelochemicals are greatly reduced. This reduces the continuous accumulation of allelochemicals in the soil from the source, preventing allelochemical poisoning of new seedling roots. Meanwhile, by not immediately removing old trees, the sudden release of harmful substances caused by root rot is avoided: if old trees are directly dug up, their roots will quickly rot in the soil, releasing a large amount of toxic and harmful substances at once, exacerbating soil pollution. This invention keeps old trees in a state of "survival but not excessive growth," keeping the roots active and preventing rot (rot accelerates the release of allelochemicals that resist continuous cropping). They are then removed after leaf fall in autumn (when the roots are still active, it is easier to remove them completely). This avoids the sudden release of harmful substances from root rot and utilizes the weak absorption effect of the living roots of old trees to consume some of the accumulated free harmful ions in the soil, reducing soil toxicity. Removing old trees after leaf fall in autumn, when the low winter temperatures inhibit microbial activity, means that even if a small amount of roots remain in the soil, they are unlikely to decompose and release toxins, completely cutting off the pathway for toxic substance replenishment. Combined with the physical isolation effect of root zone restriction, this keeps the roots of new seedlings away from the toxicity of the surrounding soil deteriorated by continuous cropping, significantly reducing the probability of stunted or dead seedlings and significantly improving the survival rate after planting.

[0041] After pruning the old tree, no fertilizer is applied, only a small amount of water is given to further limit the competition for nutrients between the old tree and the new seedlings. After the trunk is cut off, no fertilizer is applied to the old tree, only a small amount of water is added to maintain its survival. This keeps the nutrient absorption capacity of the old tree's root system at a minimum level, so it will not compete with the newly planted seedlings for nutrients in the root zone soil. This ensures that the roots of the new seedlings can obtain nutrients first, solving the problem of "new seedlings' nutrients being competed for by old tree debris / living roots" in continuous cropping, and laying a nutrient foundation for the growth of new seedlings.

[0042] This measure cuts off the material source of replanting obstacles from three dimensions: allelochemical release, sudden pollution by harmful substances, and nutrient competition. It is in line with the scientific conclusion that "accumulation of allelochemicals is the core cause of replanting obstacles" and avoids the vicious cycle of "directly digging up trees → root rot → aggravated soil toxicity" in traditional replanting. It creates a clean soil prerequisite for the subsequent ecological improvement of the root zone of new seedlings.

[0043] Second, based on the above, we can further improve the microenvironment of the root zone by modifying the microenvironment, thereby partially reconstructing the soil ecology of the healthy root zone and solving the problems of soil microecological imbalance and nutrient depletion.

[0044] The essence of grape replanting disorder is the "systemic deterioration" of the soil throughout the entire vineyard. Traditional methods of comprehensive soil improvement are difficult to implement and easily damage the soil structure. This invention adopts a core strategy of root zone restriction, precisely improving the ecological environment of only the local area where the new seedling roots grow (planting hole). This not only conforms to the growth characteristics of grape roots, where nutrient absorption and growth activities are mainly concentrated in the local root zone, but also achieves "local health" of the root zone soil through physical restriction and nutrient soil reconstruction. The scientific mechanism is as follows: (I) Physical confinement: Constructing an independent root zone space to isolate the seedlings from the toxicity of the surrounding replanted and deteriorated soil. A thin-walled plastic tube is placed in the planting hole to form a confinement structure, strictly limiting the growth space of the seedling roots within the ecological nutrient soil. This physically isolates the seedling roots from allelochemicals, harmful pathogens, and toxic ions in the surrounding replanted soil, allowing the seedling roots to grow in an independent space free from external toxins. This prevents the roots from being harmed by the replanted soil from the germination stage, solving the problem of "direct contact between seedling roots and deteriorated soil, resulting in high rates of stunted growth and seedling death" in traditional replanting. This aligns with the scientific principle that "plant root growth requires a clean and stable microenvironment."

[0045] Digging planting holes (40cm in diameter and 40cm deep) between two existing vines in the original planting row is a scientifically designed approach that considers the vineyard's existing planting layout, the distribution of toxic soil from continuous cropping, and the growth characteristics of grape roots. Its core function is to avoid severe toxicity in the main root zone of the old vines, utilize the relatively clean soil between rows to reduce stress from continuous cropping, and meet the specifications of root zone restriction techniques, creating independent, confined spaces. The first 1-2 years after planting are a period of rapid root development for grape seedlings. During this stage, the roots primarily grow as shallow, fibrous roots. The 40cm diameter and 40cm depth of the planting holes fully meet the needs of root extension, respiration, and absorption in the early stages. This avoids restricting root growth due to insufficient space, while also preventing excessive use of organic nutrient soil and increased planting costs due to excessive space. It represents the optimal specification that balances root growth needs with economic costs. The new row spacing created after planting also facilitates later cultivation and management in the orchard. Meanwhile, the planting holes of this specification are excavated in a localized, small area. Compared with full-area soil replacement and large-scale hole digging, the amount of soil excavation is small, the operation is simple, and it can be completed manually or with small agricultural machinery. The labor intensity is low and the construction efficiency is high. At the same time, the holes are only dug in a localized area between the rows, which will not damage the root distribution of the old trees (avoiding damage to the roots before removing the old trees, which may lead to premature rot). This ensures that the old trees are in a state of "survival without excessive growth" after the trunk is cut and the crown is controlled. It works in synergy with the previous old tree treatment process and is suitable for large-scale, large-scale variety replacement in vineyards.

[0046] (II) Reconstruction of Ecological Nutrient Soil: Targeted cultivation of beneficial microbial communities in the root zone achieves a triple effect of "nutrient supply + microecological regulation + soil structure improvement." Ecological nutrient soil is the core of root zone microecological improvement. Its formula and preparation process are strictly designed around the growth needs of grape roots and the goal of improving continuous cropping soil. The synergistic effect of each raw material reconstructs a healthy root zone soil ecology. The scientific mechanism is as follows: 1. Fermentation substrate provides basic carbon source and nutrients for soil microecology, taking into account both organic matter replenishment and slow nutrient release: Edible mushroom residue, livestock and poultry manure, and decomposed seed materials are mixed in a ratio of (5-6):(3-4):(1-2), which not only provides sufficient carbon and nitrogen sources for beneficial microorganisms, but also provides slow-release organic nutrients for the roots of new seedlings, solving the problem of organic matter depletion and nutrient imbalance in soils with continuous cropping; and decomposed seed materials (such as cooked soybeans) can supplement the micronutrients preferred by grapes, make up for the excessive consumption of micronutrients in soils with continuous cropping, and conform to the nutrient absorption pattern of grapes.

[0047] 2. Targeted inoculation of beneficial microorganisms with compound bacterial solutions rapidly establishes a dominant community of beneficial bacteria in the rhizosphere, inhibiting harmful pathogens: The combination of Bacillus (such as Bacillus subtilis), Trichoderma (such as Trichoderma harzianum), EM bacteria, and yeast is a scientifically selected approach based on the synergistic effects of microorganisms. Bacillus can secrete antibacterial substances, inhibiting common harmful pathogens in grape replanting, such as Fusarium and Rhizoctonia; Trichoderma harzianum destroys the mycelium of harmful fungi through hyperparasitism while promoting grape root growth; EM bacteria and yeast decompose organic matter in the soil, releasing readily available nutrients, and synergistically form a dominant microbial community with other beneficial bacteria, rapidly occupying the rhizosphere ecological niche, fundamentally solving the core problem of "microecological imbalance and rampant harmful bacteria" in replanted soils.

[0048] 3. Beneficial microorganisms achieve "harmlessness + functionality" through aerobic fermentation, improving the structure of the root zone soil: The fermentation substrate, through aerobic fermentation with compound bacterial liquid, can not only completely kill pathogens and insect eggs in the raw materials and avoid secondary pollution, but also decompose large organic molecules into small humic substances through the metabolism of microorganisms, improving the soil's water and fertilizer retention capacity; at the same time, the reproduction and metabolism of microorganisms can promote the formation of soil aggregate structure, solve the problem of "compactment and poor aeration" in continuously cropped soil, and create a good physical environment for the respiration, extension and nutrient absorption of grape seedling roots.

[0049] 4. Combine with the topsoil between the rows of vineyards to improve the compatibility of the nutrient soil with the local soil: Mix the fermentation products with the topsoil between the rows of vineyards in a certain proportion so that the physical and chemical properties of the ecological nutrient soil are compatible with the local soil. This avoids the difficulty of the new seedling roots to recover due to the large difference between the nutrient soil and the surrounding soil. It conforms to the growth law of "plant roots adapting to the local soil microenvironment" and improves the survival rate of the new seedlings.

[0050] This measure focuses on root zone restriction and follows the soil regulation principle of "local improvement is better than overall improvement". It uses physical means to isolate the toxicity of continuous cropping and achieves triple improvement of root zone micro-ecology, nutrients and soil structure through ecological nutrient soil. It precisely targets the core causes of grape continuous cropping obstacles and solves the technical defects of traditional microbial agents that are "easily diluted by the deteriorated soil due to continuous cropping when applied to the whole area, resulting in poor effect" and soil replacement and improvement that are "difficult to operate and damage the soil structure".

[0051] Third, implement precise water and fertilizer management within designated areas. This involves targeted cultivation of robust seedling root systems to enhance seedlings' resistance to continuous cropping stress and consolidate the effects of this approach.

[0052] In continuous cropping of grapes, weak seedling growth and poor stress resistance are important internal causes of stunted and dead seedlings. This invention's restricted-area precision water and fertilizer management is based on two scientific principles: "root zone restriction + nutrient requirements of grape seedlings throughout their growth cycle." It applies drip irrigation and fertilizer management only to the soil within the restricted root zone, preventing water and fertilizer loss to the surrounding continuously cropped soils while precisely supplying nutrients according to the different growth stages of the seedlings. This targeted approach cultivates robust root systems and enhances the seedlings' resistance to continuous cropping stress. Its scientific mechanism is as follows: 1. Limited-area drip irrigation: Water and fertilizer reach the roots of new seedlings directly, improving water and fertilizer utilization and preventing the activation of harmful substances in the surrounding soil. By restricting water and fertilizer application to the root zone only within the planting hole, the water and fertilizer are applied directly to the root absorption area of ​​the new seedlings, significantly improving water and fertilizer utilization. At the same time, it avoids the activation of allelochemicals and harmful ions in the surrounding soil that has been continuously planted with water and fertilizer, which would otherwise be activated and migrate to the root zone of the new seedlings. This ensures the continuous cleanliness of the root zone microenvironment, which aligns with the scientific principle that "precise water and fertilizer application is the core means of cultivating a robust root system."

[0053] 2. Phased water and fertilizer management: Matching the physiological needs of grape seedlings at different growth stages to achieve orderly growth from seedling establishment to root promotion to robust vine development. 7-10 days after transplanting, drip irrigation with biostimulants (mineral-derived potassium humate / seaweed extract): Mineral-derived potassium humate and seaweed extract can stimulate the division of grape root cells, promote the germination of adventitious roots, and at the same time enhance the root system's resistance to stress, helping seedlings to recover quickly and solving the problems of "slow seedling recovery and poor root germination" in continuous cropping.

[0054] Before the seedlings have 7-8 leaves, only apply water and do not fertilize: In the early stage after the seedlings are planted, the root system has a weak absorption capacity. At this time, not fertilizing can avoid the root burn caused by excessive nutrient concentration in the soil, and ensure the normal extension of the root system, which is in line with the growth rule of "light fertilization and heavy water retention in the seedling stage".

[0055] After the appearance of the second tendril, alternate drip irrigation with nitrogen fertilizer and balanced fertilizer: The appearance of the second tendril in grapes indicates that the root system has entered a rapid growth stage. At this time, alternating application of urea (fast-acting nitrogen fertilizer) and balanced fertilizer can not only promote the growth of branches and leaves and provide sufficient photosynthetic products for the roots, but also ensure the phosphorus, potassium and micronutrients required for root growth, so as to achieve "simultaneous promotion of branch and leaf growth and root growth", cultivate a robust root and crown system, and greatly enhance the new seedlings' resistance to continuous cropping stress.

[0056] This step deeply integrates water and fertilizer management with root zone limitations and the seedling growth cycle, following the plant physiological principle that "root nourishment precedes plant nourishment, and stress resistance stems from a robust root system." By precisely targeting water and fertilizer to cultivate a robust root system, it overcomes the obstacle of continuous cropping by enhancing the seedling's own stress resistance. This creates a synergistic effect with the previous two steps, namely "reducing external toxicity + building internal health + cultivating robust plants," upgrading the resistance to continuous cropping from "passive defense" to "active resistance."

[0057] Finally, through the synergistic effect of the above three technical modules, the solution perfectly aligns with the principles of overcoming grape replanting obstacles. In other words, the core innovation of this invention lies not in the application of a single technical means, but in the spatiotemporal synergy and mechanistic complementarity of three technical modules: old tree trunk cutting and canopy control, root zone restriction and ecological improvement, and restricted-area precision water and fertilizer management. Its overall scientific nature is reflected in: 1. Orderly connection in time and space: From the time dimension, the old tree trunk cutting and crown control creates a clean soil prerequisite for the planting of new seedlings, the root zone restriction and ecological improvement builds an independent and healthy root zone for the growth of new seedlings, and the limited-area precise water and fertilizer management cultivates a robust root and crown system for the development of new seedlings. The three links are promoted in a time sequence of "before planting - during planting - after planting". From the spatial dimension, the old tree crown control reduces the release of toxicity in the soil throughout the entire area, the root zone restriction builds a healthy ecology in the local root zone, and the water and fertilizer management provides precise supply to the root absorption area, realizing the spatial synergy of "overall pest control + local improvement + fixed-point cultivation".

[0058] 2. Mechanistic Complementarity and Reinforcement: Reducing the release of allelochemicals from the source by cutting the trunk and controlling the crown of old trees addresses the problem of "continuous input of external toxins"; Root zone restriction and ecological improvement partially reconstruct the soil ecology, addressing the problems of "root zone microecological imbalance and nutrient depletion"; and restricted-area precise water and fertilizer management cultivates plant resistance, addressing the problems of "weak seedling growth and poor resistance." These three aspects respectively target the three core levels of grape replanting obstacles: the source of substances, the growth environment, and the internal factors of the plant. Their mechanisms complement and reinforce each other, forming a comprehensive closed loop for resisting replanting problems.

[0059] 3. Conforms to the actual production conditions of the grape industry: The entire process of this invention is based on the existing planting conditions of the vineyard, without abandoning the original land and facilities, thus avoiding the waste of manpower and resources in rebuilding the vineyard; at the same time, the root zone is limited to local improvement, which is simple to operate and cost controllable. Compared with the traditional method of replacing soil and applying fungicides throughout the entire area, it is more suitable for the actual needs of large-scale grape production, and achieves the unity of technical science and industrial practicality.

[0060] The following description, in conjunction with preferred embodiments and comparative examples, further illustrates the present invention. The experiment was conducted at the Changli grape planting base in Qinhuangdao, Hebei Province, and was tracked for three years (March 20-31, 2019 to July 2022). Each experimental plot was 5m × 20m in size. The existing old grapevines in the experimental garden had a row spacing of 2m and a plant spacing of 1.5m. After the new seedlings were planted, the planting density remained unchanged at a row spacing of 2m and a plant spacing of 1.5m. The grape seedlings used in the experiment were of the Kyoho variety. The fermentation substrate was mushroom residue: sheep manure: cooked soybeans = 5.5:3.5:1. The compound bacterial solution consisted of 4 parts Bacillus subtilis + 5 parts Trichoderma harzianum + 4 parts EM bacteria + 2.5 parts yeast + 25 parts brown sugar + 50 parts water. Fermentation was carried out at 28-35℃ for 8 days. The ecological nutrient soil consisted of fermentation products: 0-20cm topsoil between rows = 4.5:5.5.

[0061] Example 1 This embodiment provides a method for grape cultivation resistant to continuous cropping, which includes: Cutting the trunk of old trees to control the crown and suppress detoxification: One day before planting new grape seedlings, cut the main trunk of the old tree to be replaced back to 45cm and do not dig it up; after the main trunk sprouts, select one new shoot from the lower part to cultivate and remove the rest of the new shoots; pinch the new shoot when it grows to 6-7 leaves, and pinch the secondary shoots once every 2-3 leaves; after cutting until the leaves fall in autumn, water only a small amount and do not fertilize. After the leaves fall in autumn of the same year (before the soil freezes), dig up the old tree with its roots.

[0062] Construction of root zone-restricted planting holes: Along the existing planting row, dig planting holes between two existing old trees, with a diameter of 40cm and a depth of 40cm; place a PVC thin-walled round pipe of the same specification into the hole to form a restricted structure, backfill the restricted hole with the above-mentioned ecological nutrient soil, water it to settle it, and then level it for later use. Planting and management of new seedlings: Soak new seedlings in clean water for 20 hours before planting, prune the roots to 11cm, and prune the main stem to leave 2-3 plump buds; plant the seedlings in the restricted planting holes, and water them thoroughly immediately after planting; use drip irrigation to manage water and fertilizer only in the restricted planting holes. Eight days after planting, drip irrigate 1.5kg of mineral-derived potassium humate per mu. Before the seedlings have 7-8 leaves, drip only clean water. After the second tendril appears, use 12kg of urea and 12kg of NPK 1:1:1 balanced fertilizer per mu alternately for drip irrigation, once every 8 days.

[0063] Subsequent management: Pruning and pest and disease control were carried out according to local grape conventional cultivation practices. No additional measures to resist continuous cropping were applied during the trial period.

[0064] Example 2 This embodiment provides a method for grape cultivation resistant to continuous cropping, which includes: Cutting the trunk of old trees to control the crown and suppress detoxification: Two days before planting new grape seedlings, cut the main trunk of the old tree to be replaced back to 40cm and do not dig it up; after the main trunk sprouts, select one new shoot from the lower part to cultivate and remove the rest of the new shoots; pinch the new shoot when it grows to 6 leaves, and pinch the secondary shoots once every 2 leaves; after cutting until the leaves fall in autumn, water only a small amount and do not fertilize. After the leaves fall in autumn of the same year, dig up the old tree with its roots.

[0065] Construction of root zone restricted planting pits: Along the existing planting row, dig planting pits between two existing old trees. The planting pits should be 40cm in diameter and 40cm deep. Place a PVC thin-walled round pipe of the same specification into the pit to form a restricted structure. Backfill the restricted pit with the above-mentioned ecological nutrient soil, water it to settle it, and then fill it with soil for later use.

[0066] New seedling planting and management: Soak new seedlings in clean water for 24 hours before planting, prune the roots to 10cm, and cut the main stem to leave 2 plump buds; plant the seedlings in the designated planting holes, and water them thoroughly immediately after planting; use drip irrigation to manage water and fertilizer only in the designated planting holes. 7 days after planting, drip 0.9kg of seaweed extract per mu. Before the seedlings have 7-8 leaves, drip only clean water. After the second tendril appears, use 10kg of urea and 10kg of NPK 1:1:1 balanced fertilizer per mu alternately for drip irrigation, once every 7 days.

[0067] Subsequent management: Keep in sync with Example 1.

[0068] Comparative Example 1 In this comparative example, the large trees of the variety to be replaced were directly uprooted. After digging, the old tree roots were cleaned, the pits were prepared, and the soil in the planting row was manually tilled to a depth of 20cm without any trunk cutting or crown control treatment. Next, along the original planting row, planting holes of the same specifications as in Example 1 (40cm in diameter and 40cm in depth) were dug at the original planting points of the old trees. The holes were backfilled with a mixture of fermented substrate and compound bacterial solution, the same as in Example 1, without placing any restrictive pipes or root zone restrictive structures. The pretreatment and planting operation of the new seedlings were the same as in Example 1.

[0069] Water and fertilizer management: Watering was carried out using the whole-area flood irrigation method, and fertilizer was applied by broadcasting throughout the garden. The type, amount, and application time of fertilizer were the same as in Example 1. Subsequent management was kept in sync with Example 1.

[0070] Comparative Example 2 This comparative example is an adjustment based on Example 1. The treatment of cutting the trunk and controlling the crown of old trees to inhibit detoxification is the same as in Example 1. However, the backfill soil in the root zone restricted planting holes formed by the same specification of PVC thin-walled round pipe is different. That is, the compound bacterial solution is centrifuged and concentrated to obtain a high concentration of wet bacteria (70% water content). The wet bacteria, sheep manure and the topsoil between rows (0-20cm) are mixed in a ratio of 2.5:2.5:6 to obtain the backfill soil.

[0071] The pretreatment, transplanting procedures, and types, amounts, and frequencies of drip irrigation and fertilization for seedlings were completely consistent with those in Example 1. Subsequent management was kept in sync with Example 1.

[0072] This experiment was conducted at the Changli grape planting base in Qinhuangdao, Hebei Province. Existing old grapevines (Kyoho variety) were planted with a row spacing of 2m and a plant spacing of 1.5m. New seedlings (Kyoho variety) were planted at the same density. All experimental groups (Examples 1 and 2) and control groups (Comparative Examples 1 and 2) had the same soil type, fertility, and number of consecutive cropping years. The grape varieties (all Kyoho), seedling age, and growth vigor of the new seedlings were also consistent. Unless otherwise specified, field management practices followed local conventional Kyoho grape cultivation standards, ensuring a single variable. The survival rate, stunted growth rate, and mortality rate of new seedlings in the year of planting were recorded. Plant height, diameter at root, and number of shoots in the second year after planting were recorded. Fruit setting rate, single fruit weight, and soluble solids content in the third year after planting were recorded. Specific results are shown in the table below. .

[0073] The results above show that the survival rates of the new Kyoho grape seedlings in Examples 1 and 2 reached 96.7% and 95.3% respectively in the year of planting, with stunted seedling rates of only 2.1% and 2.7% and seedling mortality rates as low as 1.2% and 2.0%. In contrast, the survival rate of Comparative Example 1 (direct digging of old trees without restrictions) was only 62.5%, with stunted and seedling mortality rates as high as 28.3% and 9.2% respectively. The survival rate of Comparative Example 2 (with PVC pipes but different backfill soil) was 78.9%, with stunted and seedling mortality rates reaching 15.6% and 5.5% respectively. The differences are extremely significant.

[0074] In summary, through the synergistic effect of the above-mentioned mechanisms, this invention ultimately achieves the technical effects of significantly reducing the rate of stunted and dead seedlings in grape replanting, significantly improving the survival rate of new seedlings, promoting vigorous growth, and ensuring stable fruit quality in the later stages. 1. Improved survival rate: Physical confinement of the root zone to isolate toxins + biostimulants to promote root growth and seedling establishment. This addresses the problems of root damage and slow seedling establishment in new seedlings from both environmental and plant perspectives, significantly reducing stunted and dead seedlings. This aligns with the plant growth principle of "non-toxic roots + robust roots = high survival rate". 2. Robust growth: The slow release of nutrients in the root zone ecological nutrient soil, combined with the precise supply of water and fertilizer in stages, provides continuous and balanced nutrients for the growth of new seedlings. At the same time, beneficial microorganisms promote root absorption, solving the problem of "nutrient imbalance and poor absorption" in continuous cropping, and achieving simultaneous robust growth of new seedling roots and crowns. 3. Stable quality: A robust root and crown system lays the foundation for flower bud differentiation and fruit development in the later stages of grape growth. At the same time, the continuous health of the root micro-ecology ensures nutrient absorption and stress resistance throughout the entire growth period of grapes, avoiding low fruit set and reduced fruit quality caused by continuous cropping stress. This conforms to the grape cultivation principle of "robust vines = stable yield + excellent quality".

[0075] Each technical aspect of this invention is designed based on the formation mechanism of grape replanting obstacles, the growth pattern of grape roots, and the principle of soil ecological regulation. The three major technical modules work together to form a closed loop against replanting obstacles, which not only eliminates the conditions for the formation of replanting obstacles from the source, but also reconstructs a healthy root zone ecology locally, and enhances the plant's resistance to replanting stress from the internal factors, thus having great industrial applicability.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. These modifications or substitutions, or combinations of technical features in the above embodiments that do not conflict with each other, can be made in accordance with the manner described in the embodiments. These modifications, substitutions or combinations do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for grape cultivation resistant to continuous cropping, characterized in that, include: Before planting new grape seedlings, the old vines to be replaced in the vineyard are subjected to trunk cutting, crown control and detoxification treatment. Root zone restricted planting holes are constructed between the old vines in the original planting row and backfilled with ecological nutrient soil. The pre-treated new grape seedlings are planted in the root zone restricted planting holes, and the new grape seedlings are managed with drip irrigation and fertilizer in stages only within the root zone restricted area. The trunk-cutting, crown-controlling, and detoxification treatment includes: severely cutting off old trees to retain the main trunk; after budding, selecting a single lower new shoot for cultivation and gradually pinching the tips of the new shoots and lateral shoots to control their growth; after cutting off until the autumn leaves fall in the same year, only watering is provided to maintain the tree's survival without fertilization; and after the autumn leaves fall, the old trees are removed. The construction of the root zone restricted planting pit includes: excavating planting pits of suitable size between old trees, placing thin-walled round plastic tubes matching the planting pits to form a restricted structure, backfilling the restricted structure with ecological nutrient soil and compacting it; the ecological nutrient soil is made by mixing fermentation products with the topsoil between the rows of vineyards in a certain proportion, the fermentation products are made by mixing edible mushroom residue, livestock and poultry manure and decomposed seeds in a mass ratio of (5-6):(3-4):(1-2) to form a fermentation substrate, which is obtained by aerobic fermentation with compound bacterial liquid, drying and pulverizing; the compound bacterial liquid is made by compounding Bacillus, Trichoderma, EM bacteria and yeast, adding sugar source and water, and fermenting under mesophilic conditions.

2. The method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, The pretreatment of the new grape seedlings includes: soaking in clean water, root pruning, and main stem bud pruning; the phased drip irrigation and fertilization management adjusts the type and frequency of water and fertilizer according to the growth cycle of the new grape seedlings.

3. A method for grape cultivation resistant to continuous cropping according to claim 2, characterized in that, The pretreatment of the new grape seedlings is as follows: soak in clean water for 12-24 hours, prune the roots to retain a length of 10-12cm, and prune the main stem to retain 2-3 plump buds; immediately after planting, thoroughly water the root-restricted planting hole.

4. A method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, The heavy pruning of old trees is carried out 1-2 days before the planting of new grape seedlings. The height of the main trunk after heavy pruning is 30-60cm, preferably 40-50cm.

5. A method for grape cultivation resistant to continuous cropping according to claim 4, characterized in that, The new shoots are pinched back for the first time when they have 5-8 leaves, and the lateral shoots are pinched back every 2-4 leaves.

6. A method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, The diameter and depth of the planting hole are both 30-50cm, and the thin-walled round plastic tube is a PE tube, PV tube, PVC tube or corrugated tube, with its diameter and height adapted to the planting hole.

7. A method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, In the fermentation substrate, the edible fungus residue is mushroom residue, the livestock and poultry manure is sheep manure, and the decomposed seed raw material is cooked soybeans; the raw materials of the compound bacterial liquid are: 35 parts Bacillus, 4-6 parts Trichoderma, 3-5 parts EM bacteria, 2-3 parts yeast, 20-30 parts sugar source, and 40-60 parts water; the medium temperature conditions are 25-38℃, and the cultivation and fermentation time is 7-10 days.

8. A method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, In the aforementioned ecological nutrient soil, the mixing mass ratio of fermentation products to the topsoil of 0-20cm between vineyard rows is (4-5):(5-6).

9. A method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, The specific steps of the phased drip irrigation and fertilization management are as follows: drip irrigation with biostimulants 7-10 days after planting; drip irrigation with clean water without fertilization until the seedlings have 7-8 leaves; after the seedlings grow their second tendrils, alternate drip irrigation with nitrogen fertilizer and balanced fertilizer, with each drip irrigation interval of 7-10 days.

10. A method for grape cultivation resistant to continuous cropping according to claim 1, characterized in that, The biostimulant is potassium humate or seaweed extract, with an application rate of 1-2 kg of potassium humate or 0.8-1 kg of seaweed extract per mu; the nitrogen fertilizer is urea, with an application rate of 10-15 kg per mu; and the balanced fertilizer is a compound fertilizer with equal proportions of nitrogen, phosphorus, and potassium, with an application rate of 10-15 kg per mu.

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