Root-limited cultivation method for facility sweet cherries in coastal saline-alkali land

Abstract

The invention relates to the technical field of fruit tree planting, in particular to a semi-root-limited cultivation method and system for sweet cherries in coastal saline-alkali soil facilities. A salt discharging system of non-woven fabric, a gravel guiding and discharging layer, a perforated PVC drainage pipe, an underground water storage pond and a floating ball pump is built in the greenhouse in the row direction; a root control container with the height of 0.5-0.6 m and the diameter phi of 1.0-1.2 m is semi-buried on the gravel layer, surface soil, a culture medium, fresh water sand and organic fertilizer are filled according to the ratio of 4: 2: 3: 1, double-pipeline drip irrigation and four constant-pressure drippers are arranged, and a closed loop of'salt control input and salt discharge output 'is formed. By matching with AM bacteria and silicon-based foliar nutrition, salt reversion can be inhibited, cooling and ventilation can be realized, lateral capillary roots can be promoted, the fruit setting rate, the yield of a single plant and the fruit uniformity can be improved, and the method is suitable for being popularized in southern warm and wet coastal saline-alkali soil.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of fruit tree planting, and particularly relates to a semi-limiting root cultivation method for sweet cherry in coastal saline-alkali land. BACKGROUND

[0002] Soil salinization is a worldwide problem. The area of saline-alkali land in China is about 1 million hectares, mainly distributed in the northwest, north China, northeast and coastal areas. The soil in this area is seriously salinized, and the soil is sticky and poorly permeable, resulting in low soil utilization rate and output. As an economic upsurge, the large population gathering and rapid urban development in the coastal area have brought higher demand for high-quality fruits and vegetables and living quality, promoting the development of regional science and technology agriculture, green agriculture, quality agriculture and brand agriculture. How to efficiently utilize the saline-alkali soil resources in the coastal beach land and develop high-efficiency and modern agriculture in the coastal area is an urgent production and social problem to be solved.

[0003] The coastal saline-alkali land in China has the characteristics of shallow groundwater level, strong evaporation, high salt content and mainly sodium chloride type. The plough layer is heavy and poorly permeable, which leads to the easy occurrence of capillary rise, salt back migration (commonly known as "reverse salt") and high temperature-high salt compound stress in the root zone. Under the background of rapid development of facility horticulture, the facility planting of fruit trees (especially shallow-rooted tree species) in the coastal saline-alkali land not only needs to solve the problems of salt control, salt discharge and salt prevention, but also needs to consider the root zone cooling, ventilation and precise water and fertilizer supply, and meet the economic targets of early fruit, stable yield and quality. Under the multi-target constraint, engineering water conservancy and cultivation physiology must be coupled at the root zone scale, rather than relying on single "soil replacement", "foreign soil" or "underground pipe" means.

[0004] Engineering and agronomic improvement practices show that underground drainage pipe (gravel / sand filter layer, geotextile isolation, perforated drainage pipe, collection and drainage well / pump drainage) is a common technical path to control the salt content of the root zone, enhance the leaching and drainage efficiency. However, its effectiveness depends on the pipe diameter / pore size, burial depth, spacing, filter grading and anti-blocking measures, and if it is disconnected from the upper water supply-fertilization strategy, it is easy to appear the risk of "salt back migration" after irrigation.

[0005] Sweet cherry (Prunus avium) belongs to Rosaceae, Prunus, Cerasus, and is a temperate deciduous fruit tree. It is known as the "first fruit in early spring". Its fruit is bright in appearance, delicious in taste, and rich in nutrition, which is deeply loved by consumers. In recent years, the sweet cherry industry in the warm and humid regions of the south has been expanding year by year (such as the applicant's Chinese invention patents: CN107182683A, CN108834623A, CN113348954A, etc.), and sweet cherry has gradually become a "delicious food" for farmers to increase their income. However, fruit tree planting is faced with the embarrassing situation of not enough garden area, so it can only expand the planting range to the high mountains or saline-alkali land. However, the sweet cherry root system is relatively shallow and has a limited distribution range, and the absorption capacity is weak, and it is highly sensitive to changes in the root zone environment (including salinity, aeration, temperature, and water conditions). Under poor rhizosphere environment, growth and fruiting rate are easily inhibited. The latest research and review further emphasize that cherries are sensitive to waterlogging, and choosing waterlogging-tolerant or stress-tolerant rootstocks is a key direction to improve resistance. At the same time, Prunus is generally classified as a fruit tree group that is relatively sensitive to salt stress, and there are significant differences in salt tolerance among rootstocks. Saltwater irrigation can cause a series of adverse responses in gas exchange and root physiology.

[0006] Root-Zone Restriction (RZR) / containerized cultivation application and limitations. Root-Zone Restriction is a control strategy widely explored in fruit trees and facility horticulture in recent years: by limiting the root system expansion space through containers / root control devices, etc., to control the growth of plants, promote early fruiting, and improve unit area output and fruit quality. Multidisciplinary research shows that root zone restriction is a "controllable stress" that can inhibit vegetative growth, promote flower bud differentiation and reproductive growth, and can coordinate water and fertilizer supply and tree nutrition through management means. For example, the applicant's Chinese invention patent application CN113348954A "A sweet cherry root zone restriction cultivation method in the warm and humid regions of the south" is a representative, which core idea is: under the condition of facilities, limit root devices and mixed substrates are selected, combined with staged water and fertilizer, temperature and humidity, tree shape and flower and fruit management, through the "controllable stress" of small soil volume root zone and precise irrigation and fertilization, to promote lateral roots and capillary roots to occur, to coordinate vegetative growth and reproductive growth, and to achieve early production, high yield and quality improvement. However, existing literature also suggests that if containerization / root zone restriction and external salt environment are decoupled, the risk of salt accumulation in the container is higher in the saline-alkali land or salt source continuous input scenario, and the problems of "controlling salt input and salt output" need to be solved.

[0007] At present, if sweet cherry is planted in coastal saline-alkali land, the following technical problems need to be solved: 1. Replacement of soil / massive soil: Although the replacement of soil for improvement in coastal saline-alkali soil has quick effects, it has high cost, short renewal cycle, and is easy to cause secondary salt return under the conditions of shallow groundwater and storm surge in coastal areas. Meanwhile, the replacement of soil is difficult to form a sustainable and maintainable salt discharge path; 2. Simple container / root limiting: Containerization can control, promote and accelerate growth, but under the conditions of continuous input of external salt source or strong evaporation in the shed, salt is easy to accumulate in the container. If there is no downlink path formed by the gravel drainage layer-perforated pipe-catchment well / pump discharge, it is difficult to maintain a low-salt root zone for a long time. This point has been repeatedly suggested in the review of root domain restriction and facility cultivation practice; 3. "Scale mismatch" of traditional buried pipe salt discharge: Most buried pipe schemes are arranged according to rows / land blocks, lacking direct connection and in-place docking with the bottom of single-container. In the modern management system of drip irrigation-fertilization with limited supply, if a closed loop of "controlling salt input and discharging salt output" cannot be built simultaneously, salt may still migrate periodically near the effective root zone of crops; 4. Filter discharge anti-blocking and maintenance: If the cloth / filter sleeve is not properly configured or the gravel gradation is not reasonable, the buried pipe system is easy to be blocked under the conditions of salt, suspended sand, algae / manganese deposition, etc., resulting in the attenuation of salt discharge capacity. Therefore, the engineering field proposes construction details such as filter sleeve, uniform gravel and easy dredging to prolong the service life, but the maintenance coupling with the bottom of fruit container has not yet formed a common practice. SUMMARY

[0008] In order to solve the above technical problems, the technical purpose of the present application is to provide a coastal saline-alkali soil facility sweet cherry semi-root-limiting cultivation method, which builds a root zone environment regulation and control closed loop of "upper control-lower discharge" for sweet cherry with shallow root system and poor salt tolerance under the complex conditions of coastal saline-alkali soil: through greenhouse facilities, semi-root-limiting control root containers, specific ratio of substrate, and precise supply of drip irrigation water and fertilizer, the upper end inhibits salt input; through the engineering salt discharge channel of gravel drainage layer-perforated PVC drainage pipe-water collection tank and floating ball pump discharge, the lower end accelerates salt-containing seepage discharge and cooling ventilation, thereby inhibiting salt stress and waterlogging stress, promoting lateral root / fine root occurrence, and improving early yield, high yield, and stability and replicability of quality.

[0009] In order to achieve the above purpose, the following technical solution is adopted in the present application: A coastal saline-alkali soil facility sweet cherry semi-root-limiting cultivation method, comprising the following steps: S1, building a greenhouse: selecting a greenhouse with a span of 8-10 m, a ridge height of 4.5-5 m, and a length of 35-40 m, and configuring an evaporative cooling water curtain and a fan; S2, construct a salt discharge system: along the length of the greenhouse to open a depth of 35-45 cm, 1.0-1.5 m wide planting ditch, in each planting ditch bottom middle part of another dig width 25-35 cm, 15-25 cm deep small ditch; in the planting ditch laid about 1.5-2.5 m wide non-woven fabric, the bottom of the middle part of the laying diameter 15-25 cm PVC drain pipe, the drain pipe outer wall is provided with a diameter of about 1.5-2.5 cm drain hole in the form of a quincunx, the drain pipe above 8-12 cm thick, 2-5 cm particle size of the gravel layer; one end of the drain pipe is connected with the elbow water inlet pipe which is 15-25 cm higher than the ground to flush and dredge, the other end is connected with the underground water storage tank, the storage tank is provided with an automatic floating ball pump to discharge the salt water; S3, semi-limit root planting: select a height of 0.5-0.6 m, diameter of 1.0-1.2 m PVC root control container placed on the gravel layer, backfill 25-30 cm of original soil outside the root control container, so that the container is half above the ground and half buried in the soil layer; fill the container with a substrate mixed by fertile topsoil: cultivation medium: fresh water sand: composted organic fertilizer at a mass ratio of 3.5-4.5:1.5-2.5:2.5-3.5:0.5-1.5; two drip irrigation pipes are laid along the row above the container, and a constant pressure emitter is uniformly arranged in each container; S4, variety and seedling: select a sweet cherry variety with low cold requirement, early maturity, high fruit setting rate and strong stress resistance as the main planting, and select a non-toxic and healthy 1.5-3.0 year old seedling; S5, planting and density: planting in late November to early December, row spacing 2.5-3.0 m, plant spacing 0.8-1.2 m; S6, water, fertilizer and salt regulation: precise fertilizer supply is adopted, and after germination, the diluted mother liquor is applied to each container and watered to the appropriate soil moisture content; after flowering and during fruit enlargement, silicon-based foliar fertilizer is sprayed once; AM fungus preparation is applied to the row and / or container every month to adjust pH and salt content; S7, summer root and leaf protection: shading and cooling and leaf nutrient management are implemented during June to September to inhibit temperature and protect roots; Among them, the S2-S3 makes the root control container bottom directly communicate with the gravel drainage layer, and realizes the input of salt control and the output of salt discharge through drip irrigation and pump discharge, so as to inhibit the salt, reduce the root zone salt temperature accumulation and promote the lateral root and capillary root.

[0010] As preferred, the non-woven fabric has a width of 1.8-2.2 m, which is laid on the inner wall and bottom of the planting ditch, and is used to block the fine soil and substrate particles from entering the gravel layer and prevent the drain hole from being blocked.

[0011] As preferred, the gravel layer has a thickness of 8-12 cm and a particle size of 2-5 cm; the backfilling of the original soil makes the height of the contact between the outer wall of the root control container and the original soil be 40-60% of the height of the container.

[0012] As preferred, the PVC drain pipe is provided with plum blossom-shaped holes with a diameter of 1.5-2.5 cm and a hole spacing of 4-8 cm, and the drain pipe is arranged along the row direction and is provided with a maintenance opening and a filter screen at the end.

[0013] As preferred, the underground water storage tank has a volume of 800-1500 L, is matched with a floating ball controlled submersible pump, has a start-stop water level difference of 10-20 cm, and is provided with a salt guide discharge opening leading to an outside collection and drainage ditch.

[0014] As preferred, the freshwater sand in the substrate is river sand or lake sand, and has a mass fraction of 25-35%, and the remaining components and proportions are kept as 4:2:3:1.

[0015] As preferred, two drip irrigation pipes above each root control container are respectively located at 1 / 3 and 2 / 3 of the container circumference, and four constant pressure emitters are arranged equidistantly, and the single irrigation amount is controlled to make the substrate water content reach 80-90% of the field water holding capacity.

[0016] As preferred, the silicon-based foliar fertilizer is applied at a volume concentration of 600 times dilution after flowering and at an expansion period, and the AM fungus preparation is applied once a month at 1000 times dilution, for maintaining the root zone pH at 6.0-7.0 and reducing the soluble salt content.

[0017] Further, the application also provides a coastal saline-alkali land facility sweet cherry semi-limiting root cultivation system for implementing the method, which comprises: a greenhouse with a water curtain and a fan; a planting ditch arranged along the row direction, non-woven fabric and gravel layer in the planting ditch, and a perforated PVC drain pipe, one end of the drain pipe having a bend inlet pipe higher than the ground, and one end of the drain pipe being communicated with an underground water storage tank and a floating ball pump discharge system; a semi-buried root control container and a mixed substrate in the root control container; a drip irrigation pipe and a constant pressure emitter arranged above the container; and a plant for planting sweet cherry and a conventional matching management unit.

[0018] As preferred, three planting ditches are arranged along the length direction in each greenhouse; the root control container has a height of 0.5-0.6 m and a diameter of 1.0-1.2 m; the drain pipe has a diameter of 20 cm and plum blossom-shaped holes; the water storage tank has a buried depth of about 1.5 m and a volume of about 1000 L.

[0019] The application adopts the above technical scheme, and the coordination principle of the salt removal system and the root control container can be summarized as a synergistic mechanism of "space limitation, precise salt removal, and environment coordination", and specifically as follows: 1. Space limitation and salt concentration control: The root control container is arranged in a semi-buried manner (half above ground and half buried in the soil layer), so that the root system of sweet cherry is limited in the mixed substrate in the container to form a relatively independent root zone environment. The mixed substrate (fertile topsoil, cultivation substrate, fresh water sand, and organic fertilizer configured in proportion) itself has the functions of improving salt and optimizing ventilation, so that the direct influence of the external high-salt soil on the root system is reduced; at the same time, the physical boundary of the container limits the expansion of the root system to the deep high-salt soil, so that the root system avoids contacting excessive salt. 2. Efficient drainage and salt removal of the salt removal system: The salt removal system forms a good water-permeable layer through the gravel layer (2-5 cm particles) at the bottom of the planting ditch, and the root control container is directly loaded on the gravel layer to ensure that the excess salt water in the container can be permeated through the substrate to the gravel layer. The PVC drainage pipe (with a honeycomb-shaped drainage hole) below the gravel layer can quickly collect the salt water, which is then transported to the deep buried water storage tank by the pipe, and then the salt water is discharged outside the shed by the automatic floating water pump in time, forming a complete salt removal path of "substrate permeation, gravel layer water conduction, pipe collection, and external removal", which effectively avoids the accumulation of salt in the root zone. 3. Functional synergy and salt inhibition: The semi-buried design of the root control container ensures that the salt in the root zone can be efficiently entered into the salt removal channel through water permeation; at the same time, the elbow inlet pipe of the drainage pipe can flush the pipe sediment, and the non-woven fabric pad prevents the substrate from blocking the drainage hole, so as to ensure the long-term unobstructedness of the salt removal system. In addition, the drip irrigation system above the container realizes precise water supply, which avoids the salt upward migration caused by flood irrigation, and the salt removal system simultaneously processes the excess salt that may be generated after water supply, so that the two systems cooperate to inhibit the salt phenomenon from both "salt input control" and "salt output removal", and create a low-salt and suitable soil environment for the shallow root system of sweet cherry.

[0020] In summary, the application forms a closed loop of "salt input control-salt output removal" in the root zone, so that the salt-containing percolation water is quickly discharged and the capillary upward channel is stably blocked, which significantly inhibits the salt accumulation in the container and the seasonal accumulation of salt in the container; the non-woven fabric isolation and the elbow flushing port improve the long-term unobstructedness of the filtration and drainage system, the gravel layer and the semi-buried container configuration enhance the root zone ventilation and heat dissipation, and reduce the root zone heat-salt coupling stress in the high-temperature and high-humidity season; the AM fungus and the silicon-based foliar nutrient promote the differentiation of lateral roots and capillary roots in the low-salt and suitable soil environment, shorten the seedling period, improve the fruit setting rate and fruit uniformity, and realize stable yield and quality improvement under the same or lower irrigation amount, and have maintainability and replicability. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The application is a construction photo of the planting ditch.

[0022] Figure 2Construction photos of the root control container.

[0023] Figure 3 These are construction photos of the salt drainage system.

[0024] Figure 4 This is a photograph of the cultivation system of the present invention. Detailed Implementation

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0026] Example 1: Semi-limited root system and salt removal integrated cultivation method for sweet cherry in coastal saline-alkali land S1 Facility Construction and Site Preparation 1. Greenhouse parameters: Construct single-span or multi-span greenhouses on leveled coastal saline-alkali land, preferably with a span of 8-10 m, a ridge height of 4.5-5.0 m, and a length of 35-40 m; reserve ventilation openings along the main wind direction, and configure evaporative cooling water curtains and axial flow fans (fan air exchange rate ≥40 times / h), and install roll-up film or external shading to reduce the heat load inside the greenhouse in summer.

[0027] 2. Foundation slope: The floor of the greenhouse should be sloped slightly along the length of the greenhouse, preferably with a slope of 0.2%-0.5%, to facilitate the gravity flow and drainage of the underground injection and drainage system.

[0028] 3. Seepage prevention and drainage: A ring-shaped open ditch (30-40 cm wide and 30-40 cm deep) is set on the outside of the greenhouse and connected to the main drainage ditch outside the greenhouse to prevent backflow of surface water during heavy rain.

[0029] Construction of S2 underground salt injection and drainage system 1. Planting trenches: For each individual greenhouse, dig 3 planting trenches along the length of the greenhouse, with a trench width of 1.2 m and a trench depth of 40 cm; dig a small trench (30 cm wide and 20 cm deep) at the center line of the bottom of each planting trench.

[0030] 2. Geotextile laying: such as Figure 1 As shown, non-woven geotextile (100-150 g / m²) is continuously laid on the inner wall and bottom of the planting trench. 2 The width is approximately 2.0 m, and the overlap width is ≥10 cm to prevent the overlying soil and fine particles of the matrix from entering the gravel layer.

[0031] 3. Perforated drain pipe: PVC drain pipe (outer diameter 200 mm) is laid in the middle of the ditch, and drainage holes (diameter about 20 mm) are randomly arranged on the pipe wall in the shape of a quincunx (hole distance 40-80 mm). The axis of the drain pipe is arranged along the slope. An inspection port is provided at the end of each pipe, and the other end is connected to a bend inlet pipe (the bend is about 20 cm above the ground) through a tee joint, so as to periodically flush and dredge.

[0032] 4. Backfill of filter and drainage layer: A 10 cm thick gravel layer (particle size 2-5 cm) is backfilled above the drain pipe, and is leveled and compacted to be uniform. The upper surface of the gravel layer serves as the supporting surface of the subsequent root control container.

[0033] 5. Collection and drainage: As shown in Figure 3 , the end of the drain pipe is connected to an underground water storage tank, which is preferably buried about 1.5 m deep and has an effective volume of about 1000 L. A submersible pump (rated flow 2-5 m 3 / h, head ≥8 m) controlled by a float ball is provided in the tank, and the salt-containing wastewater is discharged to the total drainage ditch outside the shed or the saltwater collection system through a corrosion-resistant pipeline. An openable manhole is provided on the top of the tank for easy maintenance.

[0034] The above-mentioned "non-woven fabric, gravel layer, perforated pipe, water storage tank, and pump discharge" constitute the drainage, collection, and discharge channels below the root zone, which are the key to realizing "salt discharge".

[0035] S3 Half-limit root control container placement 1. Container specifications and half-buried arrangement: As shown in Figure 2 , a PVC or PE root control container with a height of 0.5-0.6 m and a diameter of 1.0-1.2 m is selected, and a plurality of seepage and drainage holes (hole diameter 8-12 mm, uniformly distributed) are provided at the bottom of the container. The container is directly placed on the gravel layer, and the container is half above the ground and half buried in the soil (as shown in Figure 4 ), ensuring that the bottom surface of the container is in direct communication with the gravel drainage layer.

[0036] 2. Substrate preparation: Mix fertile topsoil, cultivation substrate (Hangzhou Jinhai Agricultural Technology Co., Ltd.), freshwater sand, and decomposed organic fertilizer (decomposed sheep manure) in a mass ratio of 4:2:3:1. Screen the topsoil to 10-20 mm, and the freshwater sand has a particle size of 0.5-2.0 mm. After measuring each component in a dry state, stir for ≥10 min until uniform, and fill the container to 5-8 cm from the top of the container.

[0037] 3. Drip irrigation above the container: Two drip irrigation pipes (outer diameter 16 mm) are laid above the container along the row, and 4 constant pressure emitters (single emitter nominal flow rate 1.6-2.0 L / h) are arranged equidistantly in each container, with the emitters at 1 / 3 and 2 / 3 of the circumference corresponding to the edge of the container. A filter with 120 or more meshes and a pressure stabilizing valve are provided in the main pipe, and a fertilizer tank or a Venturi fertilizer applicator is provided. The container is half-buried and connected to the gravel layer at the bottom, combined with the equidistant emitters above, to form a "upper control-lower drainage" isomorphic structure foundation.

[0038] S4 Variety and seedling Select early-maturing, low cold requirement, high fruit setting rate, and strong resistance sweet cherry varieties (such as Ziqiao, Hongmi, Brooks, etc.) as the main planting; select 2-year-old healthy grafted seedlings without quarantine diseases, with complete root system and up-to-standard ground diameter.

[0039] S5 Planting and spacing 1. Planting period: preferably in late November to early December after leaf fall in autumn.

[0040] 2. Density: row spacing 2.5-3.0 m, plant spacing 1.0 m.

[0041] 3. Operation points: hole planting, stretching roots, making root groups mainly distributed in the lower part of the container; after soil compaction, pour root setting water along the emitter ring in the container to near saturation of the substrate, observe whether the water outlet of the water storage tank and the pump external discharge are smooth; check the plant body inclination and substrate settlement 3-5 days after planting, and fill as necessary.

[0042] S6 Water and fertilizer integration and salt regulation 1. Basic fertilizer after germination: 7-10 days after germination, inject the basic water-soluble fertilizer mother liquor of the season into each container through the fertilizer applicator, prepare 60 times mother liquor (or equivalent combination of the same nutrient concentration) according to 20 kg / acre of pure content, and inject uniformly along the drip irrigation system.

[0043] 2. Fertilization and foliar nutrition during growth period: spray 600 times Deep-Sea Silicon Liquid Fertilizer (silicon fertilizer is Deep-Sea Silicon, provided by Yantai Shibaile Fertilizer Co., Ltd.) once on the leaves after flowering and during fruit enlargement; spray medium element water-soluble fertilizer (according to the instructions) once a month during June-September to alleviate high temperature stress and improve leaf canopy stability.

[0044] 3. Rhizosphere microbial conditioning: apply AM fungicide (provided by Shandong Chenhe Biological Technology Co., Ltd.) to the container or inter-row soil once a month, prepared at 1000 times working solution; equivalent to 5 L / acre·time, to improve rhizosphere pH and ion balance, and promote capillary root differentiation.

[0045] 4. Irrigation threshold: small water volume - high frequency drip irrigation based on substrate moisture content or tension, target to maintain container substrate moisture content at 80-90% of field water holding capacity; when container substrate electrical conductivity (EC) is higher than the preset threshold (e.g. > 3.0 mS / cm), adopt pulse drip irrigation (10-15 min each time, interval 20-30 min, cycle 2-3 times), combined with pump discharge to form salt leaching.

[0046] 5. Summer high temperature root maintenance and leaf retention: apply Guaguang Fumian, Guaguang Genhuan, Guaguang Banbao and Guaguang Yudubao (provided by Sichuan Run'er Technology Co., Ltd.) once in June and August respectively, spray Xindonggong Zhongliangyuansu medium element water-soluble fertilizer (provided by Yantai Shuhecun Technology Co., Ltd.) on leaves once a month, and automatically link water curtain and fan according to the temperature and humidity in the shed; if necessary, hang 30-50% shading net.

[0047] S7 Tree shape, flowers and fruits, and pest control 1. Tree shape: choose trunk shape, spindle shape or Y shape according to the characteristics of containerization, and follow the principle of "controlling crown and leaving fruit, promoting short branch fruiting"; light pruning is mainly used in winter pruning, and bud pruning and pinching are timely in summer.

[0048] 2. Flowers and fruits: thin flowers and fruits according to tree vigor, target uniform single fruit, and ventilated and lighted fruit table.

[0049] 3. Disease and pest control: follow green prevention and control, prefer to use physical control and low-residue preparations, and pay attention to pesticide avoidance during safe period of bee pollination.

[0050] S8 Operation maintenance and monitoring 1. Drain pipe flushing: inject clean water or low pressure water flow into the water inlet pipe for 2-5 min every month or after strong rainfall / strong evaporation season to remove sediment in the pipe; observe the turbidity of water storage tank and pump discharge flow.

[0051] 2. Filtration and emitter maintenance: clean the screen / stack filter every 2-4 weeks, and check the uniformity (CU) of emitter outflow; replace the emitter in time if it is found to be blocked.

[0052] 3. Non-woven fabric and gravel layer: check 1-2 places every quarter to confirm that the non-woven fabric is not damaged and the gravel layer is not silted by fine particles.

[0053] 4. Environmental monitoring: bury temperature and EC probes at 10-20 cm and 30-40 cm of the container substrate, and record the curve; target to maintain root zone pH 6.0-7.0 and EC within the tolerance range of crops to fluctuate smoothly.

[0054] 5. Salt water disposal: the discharge outlet of the water storage tank and the total discharge ditch outside the shed should be equipped with simple facilities such as sedimentation and neutralization according to local environmental protection standards to avoid secondary pollution.

[0055] Comparative Example 1 (only root control container, drip irrigation, no underground salt drainage system) Treatment Settings: The same size root control container (0.55 m high, φ 1.1 m) as in the example, the same substrate ratio (topsoil: cultivation substrate: fresh water sand: mature organic fertilizer = 4:2:3:1), double pipe line drip irrigation on the top, 4 constant pressure emitters per container; The non-woven fabric-stone drainage layer-perforated drain pipe-water storage pool, floating ball pump drainage system in the planting trench was cancelled, and the container was directly placed in the original soil (without a stone layer), and only a ring-shaped open ditch was reserved outside the shed.

[0056] The rest of the tree shape, flowers and fruits, and pest management were the same as in the example.

[0057] Technical points missing: no "under-drain" access and maintainable drainage link, only "upper control" irrigation and small amount of soil root zone.

[0058] Summary of results: During the high temperature stage of summer (June-August), the container substrate EC was significantly elevated, and the pulse drip irrigation appeared to migrate back 24-48 h; the fruit setting rate and yield per plant in the stable yield period of the second year were significantly lower than in the example (p<0.05), and the salt injury index was significantly increased.

[0059] Comparative Example 2 (block underground pipe salt drainage, original soil planting, unlimited root container) Treatment Settings: Salt drainage ditches were excavated along the rows (55 cm deep, 40 cm wide, about 0.1% slope), and perforated corrugated pipes (PE, φ 60 mm) wrapped with non-woven fabric were laid on them, which were covered with 10-15 cm of straw and then backfilled with original soil, with ditch spacing matching row spacing; The fruit trees were directly planted in the original soil without using root control containers and formula substrates; The drip irrigation pipes were arranged in rows (16 mm, emitter spacing 40 cm, single drip 2 L / h), and the total amount of irrigation / fertilization was equal to the nutrient caliber of the example.

[0060] Technical points missing: no "semi-unlimited root" small amount of root zone and container bottom-drainage layer co-located, salt drainage is block-scale, not point-based closed loop.

[0061] Summary of results: The EC of the plough layer is lower than that of Comparative Example 1, and the salt injury index is reduced, but due to the deeper and more scattered distribution of the root system, the soil texture is heavy and the summer high temperature, the rhizosphere aeration and heat dissipation are inferior to the example; the yield and quality indicators in the stable yield year are generally between Comparative Example 1 and the example (p<0.05).

[0062] Comparative Example 3 (semi-unlimited root, drainage, perforated pipe, but no non-woven fabric isolation and elbow flushing) Treatment Settings: The rest is the same as the example, only cancel the non-woven fabric isolation layer and the elbow water inlet pipe (dredging port); the gravel (2-5 cm, 10 cm thick) directly covers the perforated PVC (φ200 mm, 2 cm plum blossom holes), and the drainage end enters the buried water storage tank and is pumped out.

[0063] Technical points missing: lack of long-term anti-blocking and maintainable dredging structure, insufficient fine particle migration resistance of the filter and drainage layer.

[0064] Summary of results: similar to the example for 2 months before operation; since the 3rd month, the outflow of the drainage pipe gradually decreases under the dual action of high evaporation and fine particle migration, and the outflow decreases by more than 20% in the 6th-7th week, and the local outflow decreases by more than 40% in the 10th-12th week, resulting in an increase in EC of the container, a slight increase in root zone temperature, and a slight decrease in yield and quality (p<0.05) in the middle and late summer.

[0065] Test example The present application comparative example and the example are completed in the same greenhouse, the same cultivation season (two consecutive seasons), the same basic conditions of the greenhouse (span 9 m, ridge height 4.8 m, length 38 m, equipped with water curtain and axial flow fan; the ground is slightly sloped in the direction of the greenhouse at 0.3%); the water source is the same freshwater well, and the irrigation and fertilization use a unified formula (unless otherwise specified). The test uses a random block design (RCBD), with 2 replicate blocks per treatment, 10 plants per block (a total of 20 plants per treatment); the planting seedlings are the same batch of 2-year-old healthy grafted seedlings. The statistical method uses one-way ANOVA, and the post-hoc comparison uses Tukey HSD with a significance level of α=0.05. Except as specifically noted, the values are based on the second year of results (stable yield year) as the statistical yardstick, and the mean ± standard deviation is used.

[0066] The indicators and determination methods are as follows: 1. Root zone EC (dS / m): measure at 10-20 cm and 30-40 cm of the container / soil; 2. Root zone temperature (°C): buried temperature probe (15 cm); statistics of daily average from June to August; 3. Fine root length density (FRLD, km·m -3 ): ring sampling, washing, WinRHIZO image analysis; 4. Root hair density (strips·mm -1 ): fine root segment stereoscopic mirror counting; 5. Fruit setting rate (%): investigation according to fixed inflorescence marking after flowering; 6. Yield per plant (kg), average fruit weight (g), soluble solids SSC (°Brix), fruit cracking rate (%), salt injury index (0-5); 7. Salt discharge system operation: storage tank discharge volume (m 3), EC (dS / m), days required for effluent decay to 20% (d).

[0067] 8. Result data as in Tables 1-3 (stable yield year, n = 20 / treatment).

[0068] Table 1. Root zone environment and root biology indicators (mean ± SD) Statistical conclusion: the embodiment is significantly better than the three comparative examples in EC, temperature, FRLD, root hair density and salt injury index (p < 0.05); Comparative Examples 2 and 3 are better than Comparative Example 1 (p < 0.05).

[0069] Table 2. Yield and quality indicators (mean ± SD) Statistical conclusion: the embodiment is significantly higher than the comparative examples in fruit setting rate, yield per plant, fruit weight and SSC (p < 0.05), and significantly lower in fruit cracking rate (p < 0.05).

[0070] Table 3. Operation and maintenance of salt discharge system (second season June-August) Note: Comparative Example 3 lacks non-woven fabric and dredging port, and fine particle migration and algae / salt scale deposition cause rapid decay of effluent; the embodiment relies on non-woven fabric isolation and elbow flushing to maintain long-term unobstructed flow.

[0071] Discussion of results and attribution of technical effects 1. "Upper control - lower discharge" closed loop suppresses reverse salt and reduces rhizosphere temperature and salt load: The embodiment uses double-pipe drip irrigation, constant-pressure drip head limited supply, combined with container bottom - gravel drainage layer - perforated pipe - water storage tank, pump discharge, and the same position is connected, which can quickly carry salt and discharge in the leaching stage. Comparative Example 1 lacks a lower discharge link, and salt is easily migrated and accumulated in the small volume of the container after irrigation, resulting in a significant increase in EC and increased salt damage. Comparative Example 2 has a field pipe, but lacks point-by-point discharge of "single plant / single container", and the effect is between the two.

[0072] 2. Semi-buried containers and gravel layers cooperatively improve ventilation and heat dissipation: The embodiment has a significantly lower root zone temperature (28.5 °C vs 30.6-31.8 °C), which is related to the passive ventilation / heat dissipation channel formed by the semi-buried space and the gravel void; Comparative Example 1 is directly placed in the original soil, and Comparative Example 2 has deep roots distributed in heavy original soil, which are not conducive to heat dissipation and oxygen supply in summer.

[0073] 3. Long-term maintainability supports stable discharge capacity: The embodiment sets a non-woven fabric isolation, a bend dredging port, so that the second season is still not more than 20% outflow attenuation; the comparative example 3 cancels the above elements, the outflow attenuation is significantly advanced, and then causes the container EC and temperature rise, yield and quality decline in the middle and late summer.

[0074] 4, the comprehensive promotion of root system morphology and fruiting characteristics: The embodiment is significantly better than the comparative example in FRLD, root hair density, fruit setting rate, yield per plant, SSC and fruit cracking rate, which reflects the positive role of low salt, suitable soil, good ventilation / heat dissipation environment on short branch fruiting-flower bud differentiation-fruit filling.

[0075] The above is the description of the embodiments of the present application, through the above description of the disclosed embodiments, the person skilled in the art can realize or use the present application. Various modifications of these embodiments will be apparent to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A semi-limiting root cultivation method for sweet cherry in coastal saline-alkali land facilities, comprising the following steps: S1, building a greenhouse: selecting a greenhouse with a span of 8-10 m, a ridge height of 4.5-5 m, and a length of 35-40 m, and configuring an evaporative cooling water curtain and a fan; S2, constructing a salt draining system: a planting ditch with a depth of 35-45 cm and a width of 1.0-1.5 m is opened along the length direction of the greenhouse, and a small ditch with a width of 25-35 cm and a depth of 15-25 cm is additionally dug in the middle of the bottom of each planting ditch; a non-woven fabric with a width of about 1.5-2.5 m is laid in the planting ditch, a PVC drainage pipe with a diameter of 15-25 cm is laid in the middle of the bottom of the ditch, the outer wall of the drainage pipe is provided with drainage holes with a diameter of about 1.5-2.5 cm distributed in a plum blossom shape, a gravel layer with a thickness of 8-12 cm and a particle size of 2-5 cm is laid above the drainage pipe; one end of the drainage pipe is connected to a elbow water inlet pipe which is 15-25 cm higher than the ground to facilitate flushing and dredging, and the other end is connected to an underground water storage tank, an automatic floating ball pump is arranged in the water storage tank to drain the salt-containing water; S3, semi-limited root planting: a PVC root control container with a height of 0.5-0.6 m and a diameter of 1.0-1.2 m is placed above the gravel layer, and 25-30 cm of original soil is backfilled outside the root control container so that half of the container is above the ground and half is buried in the soil layer; the container is filled with a substrate mixed by fertile topsoil: cultivation medium: fresh water sand: decomposed organic fertilizer at a mass ratio of 3.5-4.5: 1.5-2.5: 2.5-3.5: 0.5-1.5; two drip irrigation pipes are laid along the row above the container, and constant pressure emitters are uniformly arranged in each container; S4, variety and seedling: a sweet cherry variety with low cold requirement, early maturity, high fruit setting rate and strong stress resistance is selected as the main cultivar, and a 1.5-3.0 year old seedling which is non-toxic and strong is selected; S5, planting and density: planting is carried out from late November to early December, the row spacing is 2.5-3.0 m, and the plant spacing is 0.8-1.2 m; S6, water, fertilizer and salt regulation: water and fertilizer integrated precision fertilizer supply is adopted, diluted mother liquor is applied to each container once after germination, and water is irrigated to the appropriate soil moisture content; silicon-based foliar fertilizer is sprayed once after flowering and during fruit enlargement; AM fungus preparation is applied to the row and / or the container every month to adjust pH and salt; S7, summer root maintenance and leaf protection: shading and cooling and leaf nutrient management are implemented during June-September to suppress temperature and protect roots; wherein, S2-S3, the bottom of the controlled root container is directly connected with the gravel drainage layer, and the controlled salt input and the drained salt output are realized by drip irrigation limited supply and water pool pump drainage to inhibit reverse salt, reduce root zone salt temperature accumulation, and promote lateral roots and capillary roots.

2. The method according to claim 1, characterized in that, The non-woven fabric has a width of 1.8-2.2 m and is laid on the inner wall and bottom of the planting trench to prevent fine soil and matrix particles from entering the gravel layer and to prevent the drainage holes from being blocked.

3. The method according to claim 1, characterized in that, The gravel layer has a thickness of 8-12 cm and a particle size of 2-5 cm; the backfilling of the original soil makes the contact height between the outer wall of the controlled root container and the original soil 40-60% of the container height.

4. The method according to claim 1, characterized by, The PVC drainage pipe is provided with a plum blossom-shaped drainage hole with a hole diameter of 1.5-2.5 cm and a hole spacing of 4-8 cm, and the drainage pipe is arranged along the row direction and provided with a maintenance opening and a filter screen at the end.

5. The method of claim 1, characterized in that, The underground water storage tank has a volume of 800-1500 L and is equipped with a float-controlled submersible pump with a water level difference of 10-20 cm between start and stop, and a salt drainage outlet is provided to lead to the outside collection and drainage ditch of the greenhouse.

6. The method of claim 1, characterized in that, The freshwater sand in the matrix is river sand or lake sand with a mass fraction of 25-35%, and the remaining components and proportions are maintained at 4:2:3:

1.

7. The method of claim 1, characterized in that, Two drip irrigation pipes above each controlled root container are located at 1 / 3 and 2 / 3 of the container circumference, respectively, and four constant-pressure emitters are arranged equidistantly, with a single irrigation amount controlled to make the matrix water content reach 80-90% of the field water holding capacity.

8. The method of claim 1, characterized in that, The volume concentration of the silicon-based foliar fertilizer is 600 times dilution after flowering and at the swelling stage, and the AM fungus preparation is applied once a month at 1000 times dilution to maintain the root zone pH at 6.0-7.0 and reduce soluble salt.

9. A coastal saline facility sweet cherry semi-limit root cultivation system for implementing the method of claim 1, characterized by, The system comprises: a greenhouse with a water curtain and a fan; planting trenches arranged along the row direction, non-woven fabrics, gravel layers, and perforated PVC drainage pipes in the trenches, the drainage pipes having a bend inlet pipe protruding above the ground at one end and being connected to an underground water storage tank and a float ball pump drainage system at the other end; semi-buried controlled root containers placed on the gravel layer and mixed matrixes in the containers; drip irrigation pipes and constant-pressure emitters arranged above the containers; and a plant unit for planting sweet cherry and conventional supporting management units.

10. The system according to claim 9, characterized in that Three planting trenches are arranged along the length direction in each greenhouse; the controlled root container has a height of 0.5-0.6 m and a diameter of 1.0-1.2 m; the drainage pipe has a diameter of 20 cm and plum blossom-shaped drainage holes; the water storage tank has a buried depth of about 1.5 m and a volume of about 1000 L.

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