Container root limiting cultivation method for cocktail grapefruit

Abstract

The invention belongs to the technical field of fruit tree cultivation, and particularly relates to a container root limiting cultivation method for cocktail grapefruit. The cultivation method comprises the following steps: (1) planting grapefruit seedlings in planting containers, and arranging the planting containers according to a wide-narrow row mode; (2) performing fertilizer and water management, treetop pruning, crown control and pest and disease damage management on the seedlings of the grapefruit. According to the cultivation method, the tree vigor is controlled and water is properly controlled through plastic container root limiting cultivation, and the problems that the vigor of the grapefruit trees is vigor, the soluble solid content is generally low, and the difference of the soluble solid content every year is large due to the influence of rainfall in the current year can be solved; and the purposes of facilitating operation, reducing the cost, improving fruits and stabilizing the yield can be achieved through root-limited cultivation in the plastic container.

Description

Technical Field

[0001] This invention belongs to the field of fruit tree cultivation technology, specifically relating to a container-based root-limited cultivation method for grapefruit. Background Technology

[0002] Cocktail grapefruit, a hybrid of Siamese sweet pummelo and Fruamandarin, has high nutritional and economic value due to its tender, juicy flesh, low acidity, sweet taste, and rich content of vitamin C, flavonoids, and other active ingredients. It has been widely cultivated in Zhejiang, Yunnan, Fujian, and other regions. However, its intrinsic quality is significantly affected by cultivation management methods and environmental factors, especially its generally low soluble solids content, which is greatly influenced by fluctuations in annual rainfall. This results in unstable fruit quality, hindering the large-scale development of the industry.

[0003] Existing technical solutions for improving citrus quality have significant limitations: While greenhouse rain-sheltered cultivation can control moisture, the construction cost is as high as 30,000 to 100,000 yuan per mu, and year-round artificial watering is required, which greatly increases production costs; Traditional root-limiting cultivation (such as building high ridges, laying film at the bottom, and using cement boards as barriers) has problems such as excessively deep taproots, outward expansion of the root system, or complex operation, resulting in poor root-limiting effects; Mulching for water control relies on permeable materials, and its water control effect is unstable in rainy areas or during concentrated rainfall; Soil moisture regulation methods require precise monitoring of growth stage needs, which is difficult to implement in practice.

[0004] None of the aforementioned methods can simultaneously achieve cost-effectiveness, ease of operation, and quality stability. Especially considering the unique biological characteristics of the grapefruit, existing technologies struggle to achieve synergistic optimization of tree vigor control and water management. Therefore, developing a low-cost, easy-to-operate cultivation technique that can consistently increase the soluble solids content of the fruit is crucial for promoting the high-quality development of the grapefruit industry. Summary of the Invention

[0005] Based on this, the present invention provides a method for container-based root-limited cultivation of grapefruit. By controlling tree vigor and appropriate water control through plastic container-based root-limited cultivation, the problem of generally low soluble solids content in vigorous grapefruit trees and the large annual variation in soluble solids content due to the influence of annual rainfall can be solved. Furthermore, plastic container-based root-limited cultivation can achieve the goals of easy operation, reduced costs, improved fruit quality, and stable yield.

[0006] To achieve the above objectives, the present invention can adopt the following technical solutions: This invention provides a container-grown, root-limited cultivation method for grapefruit, the method comprising: (1) Plant the grapefruit seedlings in planting containers and arrange the planting containers in a wide-narrow row pattern; (2) Fertilizer and water management, pruning of tree tops and control of tree crowns, and management of diseases and pests for grapefruit seedlings.

[0007] Preferably, in the above cultivation method, the planting container is barrel-shaped, with holes on the sides and / or bottom.

[0008] Preferably, in the above cultivation method, the planting container meets one or more of the following conditions: (a1) A hole is provided on each of the four sides of the planting container, namely the east, south, west and north sides; (b1) The bottom of the planting container has three or more holes; (c1) The diameter of the hole is 2.5cm-3.5cm; (d1) The height of the planting container is 45cm-55cm; (e1) The diameter of the bottom section of the planting container is 35cm-40cm, and the diameter of the top section is 60cm-65cm; (f1) The side hole is located 20cm-25cm from the bottom.

[0009] Preferably, in the above cultivation method, the narrow row spacing is 1m-1.2m and the wide row spacing is 2m-2.4m; and / or the plant spacing per row is 1m-1.2m.

[0010] Preferably, in the above cultivation method, the planting substrate includes red soil, organic fertilizer and coconut coir, with a mass ratio of (6-8):(1-3):1; and / or the amount of substrate added is 8cm-12cm from the top of the bucket.

[0011] Preferably, the above cultivation method satisfies one or more of the following conditions: (a2) Fertilizer and water management includes: watering the grapefruit seedlings every 3 to 5 days after transplanting; applying the first fertilizer when the seedlings begin to sprout new buds; then applying fertilizer every 30 days or so until 2 months before the first flowering, with each application being 30g-50g; keeping the soil moist at all times for 12 months after transplanting, maintaining the soil moisture content at 65%-75%; and maintaining the soil moisture content at 50%-60% until 40 days before fruit ripening. (b2) Pruning treetops includes: removing treetops 20cm and below, and shortening treetops above 20cm; (c2) Canopy control includes: controlling the crown width to 1.1m-1.3m and the plant height to 1.7m-1.9m; (d2) Pest and disease management includes: when each batch of new shoots grows to 0.8cm-1.2cm, pest and disease control should be carried out.

[0012] More preferably, in the above cultivation method, the type of fertilizer used is a high-nitrogen citrus-specific fertilizer or compound fertilizer.

[0013] Preferably, in the above cultivation method, irrigation is carried out using an irrigation system, which includes a main pipe, branch pipes and nozzles. The branch pipes are connected to the nozzles, and one nozzle corresponds to one planting container. The diameter of the main pipe is 50mm-75mm, and the diameter of the branch pipes is 31mm-33mm.

[0014] Preferably, in the above cultivation method, the planting container is covered with weed control fabric; and / or the planting site is covered with weed control fabric.

[0015] The beneficial effects of this invention include: (1) The cultivation method provided by the present invention achieves root restriction and water control through container cultivation, thereby controlling the vigorous growth of the tree and improving the quality of fresh fruit. In addition, container root restriction cultivation greatly reduces the amount of labor required for weeding, fertilization and pruning. Furthermore, container root restriction cultivation increases the planting density and the number of plants, thereby increasing the yield while achieving precise yield control.

[0016] (2) The cultivation method provided by the present invention uses container cultivation. The main cost is the cost of purchasing plastic planting buckets. It achieves root restriction, water control, and control of tree vigorous growth with a low cost, thereby improving the quality of fresh fruit. Plastic planting buckets can be purchased directly without being restricted by soil conditions. The site only needs to be relatively flat. The method is simple, easy to operate, and easy to promote. After container root restriction cultivation, the soil in which the plants grow is all inside the bucket. The external soil conditions have little impact on the growth of the plants. Therefore, the entire site can be covered with weed control cloth, and another weed control cloth can be covered inside the bucket. The labor required for weeding is extremely low.

[0017] (3) The cultivation method provided by the present invention adopts a small crown tree-shaped cultivation mode, which greatly reduces the amount of labor required for pruning; in addition, the present invention adopts a dense planting method, which increases the planting density and the number of plants, and while increasing the yield, it can accurately control the yield, achieve high and stable yield, high fruit quality, good consistency, and good marketability.

[0018] (4) The cultivation method provided by the present invention requires very little labor for daily management, mainly fertilization and irrigation during the dry season. A normal laborer can manage 40-50 mu, which will greatly alleviate the current problem of labor shortage in agricultural production. Attached Figure Description

[0019] Figure 1 This is a floor plan of the potted plant. In the diagram, 1: main pipe; 2: branch pipe; 3: nozzle; d1: wide row spacing; d2: narrow row spacing; d3: row spacing. Detailed Implementation

[0020] The embodiments described are provided to better illustrate the present invention, but are not intended to limit the scope of the invention to the embodiments described. Therefore, non-essential improvements and adjustments made to the embodiments by those skilled in the art based on the above description are still within the scope of protection of the present invention.

[0021] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. Singular expressions include plural expressions unless they have a distinct meaning in the context. As used herein, it should be understood that terms such as “comprising,” “having,” “including,” are intended to indicate the presence of features, numbers, operations, components, parts, elements, materials, or combinations thereof. The terminology of the invention is disclosed in the specification and is not intended to exclude the possibility that one or more other features, numbers, operations, components, parts, elements, materials, or combinations thereof may be present or added. As used herein, “ / ” may be interpreted as “and” or “or,” depending on the context.

[0022] This invention provides a container-grown, root-limited cultivation method for grapefruit, the cultivation method comprising: (1) Plant the grapefruit seedlings in planting containers and arrange the planting containers in a wide-narrow row pattern; (2) Fertilizer and water management, pruning of tree tops and control of tree crowns, and management of diseases and pests for grapefruit seedlings.

[0023] It should be noted that this invention, through root-restricted cultivation in plastic containers to control tree vigor and appropriate water control, can solve the problems of generally low soluble solids content in vigorous grapefruit trees and the significant annual variations in soluble solids content due to the influence of annual rainfall. Furthermore, root-restricted cultivation in plastic containers facilitates operation, reduces costs, improves fruit quality, and stabilizes yield. Specifically, the cultivation method provided by this invention uses root-restricted cultivation in plastic containers, allowing for the planting of 300-370 trees per acre. The planting cost per tree is approximately 60 yuan, and the annual production and management cost is approximately 8-10 yuan. The first batch of fruit can be harvested after 18 months, with each tree bearing approximately 20 fruits, weighing about 10 kg. The selling price of the grapefruit produced by this invention is approximately 8 yuan / kg, thus the initial investment can be basically recovered within 18 months. Subsequent annual investment per acre is approximately 3,000-4,000 yuan, with a yield of 4-4.5 tons per acre and a profit of 28,000-32,000 yuan per acre.

[0024] In some specific examples, the above cultivation method uses a barrel-shaped planting container with holes on the sides and / or bottom.

[0025] It should be noted that the planting container of the present invention is known in the art. It is generally barrel-shaped and has holes on the sides and / or bottom to provide ventilation and drainage.

[0026] In some specific examples, in the above cultivation methods, the planting containers meet one or more of the following conditions: (a1) A hole is provided on each of the east, west, south and north sides of the planting container; specifically, the holes on the side of the planting container can be provided on each of the east, west, south and north sides. (b1) The bottom of the planting container is provided with three or more holes; specifically, the bottom of the planting container can be provided with three or more holes, preferably three holes, as three holes can meet the drainage requirements and also retain a sufficient amount of water; (c1) The diameter of the hole is 2.5cm-3.5cm; specifically, the diameter of the hole can preferably be 2.5cm-3.5cm, such as 2.7cm, 3cm or 3.3cm, etc., and the hole with this diameter can better facilitate ventilation, drainage and water retention; (d1) The height of the planting container is 45cm-55cm; specifically, the height of the planting container can be 45cm-55cm, such as 47cm, 50cm or 53cm, etc. (e1) The diameter of the bottom section of the planting container is 35cm-40cm, and the diameter of the top section is 60cm-65cm; specifically, the diameter of the bottom section of the planting container is 35cm-40cm, such as 36cm, 37cm, 38cm or 39cm, etc.; the diameter of the top section is 60cm-65cm, such as 61cm, 62cm, 63cm or 64cm, etc.; in addition, the diameter of the bottom section, the diameter of the top section and the height of the container determine the volume of the planting container, the volume of the planting container determines the amount of substrate used, and the amount of substrate used determines the size of the grapefruit plant, so as to obtain grapefruit plants that are easy to manage and meet the yield requirements. (f1) The side holes are located 20cm-25cm from the bottom; specifically, the side holes are preferably located 20cm-25cm from the bottom, such as 21cm, 22cm, 23cm or 24cm, which is about the middle of the planting container, which is more conducive to ventilation and drainage.

[0027] In some specific examples, in the above cultivation method, the narrow row spacing is 1m-1.2m and the wide row spacing is 2m-2.4m.

[0028] It should be noted that the wide and narrow row distribution pattern can be a narrow row spacing of 1m-1.2m (e.g., 1.05m, 1.1m or 1.15m, etc.) and a wide row spacing of 2m-2.4m (e.g., 2.1m, 2.2m or 2.3m, etc.), which can allow 300-370 plants per acre, making management easier while achieving optimal yield.

[0029] In some specific examples, the plant spacing in each row in the above cultivation method is 1m-1.2m.

[0030] It should be noted that the plant spacing in each row is 1m-1.2m, such as 1.05m, 1.1m or 1.15m.

[0031] In some specific examples, the cultivation method described above uses a substrate consisting of red soil, organic fertilizer, and coconut coir in a mass ratio of (6-8):(1-3):1.

[0032] It should be noted that the substrate used for planting in this invention is known in the art. Preferably, it includes red soil, organic fertilizer and coconut coir, with a mass ratio of (6-8):(1-3):1, such as 6.5:1.5:1, 7:1.5:1 or 7:2:1, etc. This substrate is more conducive to the growth of Cocktail grapefruit.

[0033] In some specific examples, in the above cultivation method, the amount of substrate added is 8cm-12cm from the top of the bucket.

[0034] It should be noted that in this invention, the substrate is added at a distance of 8cm-12cm from the top of the container, for example, 9cm, 10cm, or 11cm. This amount allows for better growth of the grapefruit with a relatively small amount of substrate.

[0035] In some specific examples, the above cultivation methods satisfy one or more of the following conditions: (a2) Fertilizer and water management includes: watering the grapefruit seedlings every 3 to 5 days after transplanting; applying the first fertilizer when the seedlings begin to sprout new buds; then applying fertilizer every 30 days or so until 2 months before the first flowering, with each application being 30g-50g; keeping the soil moist at all times for 12 months after transplanting, maintaining the soil moisture content at 65%-75%; and maintaining the soil moisture content at 50%-60% until 40 days before fruit ripening. (b2) Pruning treetops includes: removing treetops 20cm and below, and shortening treetops above 20cm; (c2) Canopy control includes: controlling the crown width to 1.1m-1.3m and the plant height to 1.7m-1.9m; (d2) Pest and disease management includes: when each batch of new shoots grows to 0.8cm-1.2cm, pest and disease control should be carried out.

[0036] It should be noted that the fertilizer and water management, pruning of tree branches, canopy control and pest and weed management in the cultivation method of the present invention can adopt methods known in the art, preferably the methods exemplified above, which are more conducive to increasing the yield of Cocktail Grapefruit.

[0037] In some specific examples, the above cultivation methods involve applying high-nitrogen citrus-specific fertilizers or compound fertilizers.

[0038] It should be noted that the types of fertilizers used in this invention are well-known in the art, such as high-nitrogen citrus-specific fertilizers or compound fertilizers.

[0039] In some specific examples, in the above cultivation method, irrigation is carried out using an irrigation system, which includes a main pipe, branch pipes and nozzles. The branch pipes are connected to the nozzles, and one nozzle corresponds to one planting container. The diameter of the main pipe is 50mm-75mm, and the diameter of the branch pipes is 31mm-33mm.

[0040] It should be noted that, referring to Figure 1 During cultivation, an irrigation system can be configured. The irrigation system can be set up in the manner described above, which can make it easier to irrigate the plants and reduce labor costs.

[0041] In some specific examples, the above cultivation method involves covering the planting container with a weed-proof cloth.

[0042] In some specific examples, the planting area is covered with weed control fabric.

[0043] It should be noted that covering the planting container with weed control fabric or covering the planting site with weed control fabric can effectively control weeds.

[0044] To better understand the present invention, specific examples are provided below to further illustrate the content of the present invention, but the content of the present invention is not limited to the examples below.

[0045] Example 1 (1) Select a plastic planting bucket with an upper diameter of 60cm, a bottom diameter of 36cm and a height of 50cm. Drill three 3cm diameter water outlet holes at the bottom of the bucket and drill one 3cm diameter water outlet hole in each of the four directions (east, west, south, and north) at a height of 20cm.

[0046] (2) The plants are arranged in a wide and narrow row pattern. The plant spacing is set at 1m and the row spacing is 1.2m (narrow row) / 2.4m (wide row). 370 plants can be planted per mu.

[0047] (3) The substrate for planting is a mixture of red soil, organic fertilizer and coconut coir in a mass ratio of 7:2:1. After the substrate is prepared, it is placed in a plastic planting bucket. It should not be filled too full. Fill it to 10cm from the top of the bucket. Then plant the grapefruit seedlings in the bucket and water them thoroughly. Water each seedling with 15-18L of water.

[0048] (4) Based on the area size, the main pipe uses 75 PU agricultural pipe and the branch pipe uses 32 PU agricultural pipe. The plug-in type near-ground micro-spraying is adopted, and each bucket is connected to 1 nozzle.

[0049] (5) After planting the grapefruit seedlings, water them every 3 days, each time with 6-8L of water. When the seedlings start to sprout new buds, apply the first fertilizer, 30g of high-nitrogen lemon-specific fertilizer produced by Yuxi Fertilizer Plant. Then apply fertilizer every 30 days until 2 months before the first flowering, 30g each time. Later, the amount can be increased to 40-50g depending on the tree vigor. Just sprinkle it in the bucket. Keep the soil moist for 12 months after planting, and keep the soil moisture content at about 70%. Keep the soil moisture content at 50-60% for 40 days before the fruit ripens, which is conducive to the accumulation of soluble solids.

[0050] (6) No major pruning is done during the young tree stage. The main task is to remove shoots less than 20cm and shorten excessively long shoots to promote rapid growth of young trees. After fruiting, the trees should be cultivated according to the small crown shape to control vigorous growth. The crown width should be controlled at about 1.2m and the plant height at about 1.8m.

[0051] (7) When each batch of new shoots grows to about 1cm, pest and disease control should be carried out. For autumn shoots, conventional garden cleaning pesticides are sufficient. For spring shoots, the main focus is on preventing thrips and aphids. For summer shoots, the focus is on preventing leaf miners to ensure that each batch of new shoots can grow normally.

[0052] (8) Cover the planting bucket with a piece of water-permeable weed control cloth, and cover the entire planting area with weed control cloth.

[0053] Following the above technical plan, 96 plants were planted in March 2021 at the Ruili Station experimental base of the Yunnan Academy of Agricultural Sciences' Tropical Crops Research Institute in Ruili City, Yunnan Province. The control group consisted of 45 plants planted in March 2020 at the same experimental base, with a plant spacing of 2 meters. The trees were 4m tall and managed according to the "Technical Regulations for Citrus Cultivation" (NY_T975-2006). Both planting models flowered for the first time in March 2022, with the first batch of fruit ripening at the end of September. A second flowering occurred in March 2023, with the second batch of fruit ripening in September of the same year. According to experimental surveys, in 2022, the average yield per tree was 8.1 kg, the average weight of a single fruit was 421 g, and the average soluble solids content (measured using a PocketPAL-1 handheld sugar meter) was 12.4%. In 2023, the average yield per tree was 9.9 kg, the average weight of a single fruit was 508 g, and the average soluble solids content was 12.27%. Compared with conventional cultivation, the technology of this invention can enter the fruiting period one year earlier, and the yield in the first year is 64% higher than that of conventional cultivation, with an average increase of 3.07 percentage points in soluble solids content; the yield in the second year is 30% higher than that of conventional cultivation, with an average increase of 2.81 percentage points in soluble solids content. Both quality and yield are significantly improved, as shown in Table 1 below.

[0054] Table 1. Comparison of yield and quality between root-restricted cultivation and conventional cultivation over two years.

[0055] 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 it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A container-grown, root-limited cultivation method for grapefruit, characterized in that, Cultivation methods include: (1) Plant the grapefruit seedlings in planting containers and arrange the planting containers in a wide-narrow row pattern; (2) Fertilizer and water management, pruning of tree tops and control of tree crowns, and management of diseases and pests for grapefruit seedlings.

2. The cultivation method according to claim 1, characterized in that, The planting container is barrel-shaped with holes on the sides and / or bottom.

3. The cultivation method according to claim 2, characterized in that, The planting container meets one or more of the following conditions: (a1) A hole is provided on each of the four sides of the planting container, namely the east, south, west and north sides; (b1) The bottom of the planting container has three or more holes; (c1) The diameter of the hole is 2.5cm-3.5cm; (d1) The height of the planting container is 45cm-55cm; (e1) The diameter of the bottom section of the planting container is 35cm-40cm, and the diameter of the top section is 60cm-65cm; (f1) The side hole is located 20cm-25cm from the bottom.

4. The cultivation method according to any one of claims 1 to 3, characterized in that, The narrow row spacing is 1m-1.2m, and the wide row spacing is 2m-2.4m; and / or The spacing between plants in each row is 1m-1.2m.

5. The cultivation method according to any one of claims 1 to 3, characterized in that, The planting substrate consists of red soil, organic fertilizer, and coconut coir in a mass ratio of (6-8):(1-3):1; and / or The substrate should be added at a distance of 8cm-12cm from the top of the bucket.

6. The cultivation method according to claim 4, characterized in that, The planting substrate consists of red soil, organic fertilizer, and coconut coir in a mass ratio of (6-8):(1-3):1; and / or The substrate should be added at a distance of 8cm-12cm from the top of the bucket.

7. The cultivation method according to claim 1, 2, 3 or 6, characterized in that, The cultivation method meets one or more of the following conditions: (a2) Fertilizer and water management includes: watering the grapefruit seedlings every 3 to 5 days after transplanting; applying the first fertilizer when the seedlings begin to sprout new buds; then applying fertilizer every 30 days or so until 2 months before the first flowering, with each application being 30g-50g; keeping the soil moist at all times for 12 months after transplanting, maintaining the soil moisture content at 65%-75%; and maintaining the soil moisture content at 50%-60% until 40 days before fruit ripening. (b2) Pruning treetops includes: removing treetops 20cm and below, and shortening treetops above 20cm; (c2) Canopy control includes: controlling the crown width to 1.1m-1.3m and the plant height to 1.7m-1.9m; (d2) Pest and disease management includes: when each batch of new shoots grows to 0.8cm-1.2cm, pest and disease control should be carried out.

8. The cultivation method according to claim 7, characterized in that, The fertilizer used is a high-nitrogen citrus-specific fertilizer or compound fertilizer.

9. The cultivation method according to claim 1, 2, 3, 6 or 8, characterized in that, During cultivation, an irrigation system is used for irrigation. The irrigation system includes a main pipe, branch pipes, and sprinklers. The branch pipes are connected to the sprinklers, and one sprinkler corresponds to one planting container. The diameter of the main pipe is 50mm-75mm, and the diameter of the branch pipes is 31mm-33mm.

10. The cultivation method according to claim 1, 2, 3, 6 or 8, characterized in that, Cover the planting containers with weed control fabric; and / or The planting area is covered with weed-proof cloth.

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