Soybean cultivation device for low-nitrogen resistance identification

Abstract

The invention relates to the technical field of soybean cultivation, and discloses a soybean cultivation device for low nitrogen resistance identification, comprising: a nutrition supply center provided with a main adjusting liquid cavity and a plurality of nutrient solution cavities arranged independently in a surrounding manner; the cultivation units are annularly distributed outside the nutrition supply center, and each cultivation unit at least comprises an independent cultivation cavity; the liquid-gas conveying system comprises a liquid conveying assembly and a subsurface vortex forming unit, and rising vortex is generated at the bottom of a culture cavity through a rotating ejector. Through the accurate nutrient solution gradient configuration system, accurate control over a multi-concentration nitrogen environment needed by soybean low-nitrogen resistance identification is achieved; the main adjusting liquid cavity stores high-concentration nitrogen mother liquid, the mother liquid is quantitatively injected into each independent nutrient liquid cavity through a spiral array nozzle of the multi-channel dynamic uniform mixer, stable gradient working liquid is formed, it is ensured that experimental conditions are repeatable, the concentration is accurate and controllable, and a reliable basis is provided for low-nitrogen-resistant germplasm screening.

Description

Technical Field

[0001] This invention relates to the field of soybean cultivation technology, specifically to a soybean cultivation device for identifying low-nitrogen tolerance. Background Technology

[0002] Traditional soybean cultivation devices typically employ static or simple circulating nutrient solution systems to provide plants with basic water and nutrients. These devices generally lack the ability to actively regulate the root microenvironment, and the simple nutrient solution flow pattern makes it difficult to effectively promote sufficient contact between roots and the nutrient solution. Gas supply often uses uniformly distributed aeration methods, failing to provide targeted oxygen supply to densely rooted areas, resulting in low root absorption efficiency. In terms of canopy environment control, traditional devices often only adjust humidity and CO2 concentration through simple spraying or air circulation, lacking the ability to precisely regulate the canopy microenvironment and failing to meet the requirements for accurate simulation of the microenvironment under low nitrogen stress conditions.

[0003] In low-nitrogen tolerance identification experiments, the limitations of traditional devices are particularly prominent. First, their gas-liquid exchange efficiency is low, and the nutrient solution flow pattern is simple, making it impossible to effectively simulate the root system's absorption of nitrogen sources under low-nitrogen conditions. This results in experimental results that cannot accurately reflect the true physiological response of soybeans under low-nitrogen conditions. Second, the precision of environmental control is insufficient, making it difficult to achieve independent and precise control of the root and canopy microenvironments. This makes it difficult to accurately control experimental conditions when simulating low-nitrogen stress of different intensities, resulting in poor data reliability.

[0004] Traditional apparatus also struggles to support multi-gradient parallel experiments. Lacking an independent system for preparing multiple nutrient solutions, experiments are typically limited to a single nitrogen concentration, preventing simultaneous testing of multiple gradients of low-nitrogen stress. Even with multi-tank designs, maintaining independent and stable nutrient solution concentrations between tanks is difficult, leading to cross-interference and affecting the statistical reliability of experimental results. Furthermore, traditional environmental monitoring systems are relatively simple, usually only monitoring basic parameters such as pH and EC, lacking real-time, comprehensive monitoring capabilities of the rhizosphere and canopy microenvironments, hindering timely detection and adjustment of experimental conditions.

[0005] Furthermore, the lack of coordination in environmental control between the root zone and the canopy zone, with root zone aeration often affecting the canopy microenvironment, leads to mutual interference of experimental conditions and further reduces the reliability of experimental data. These limitations make it difficult for traditional soybean cultivation devices to provide accurate and reproducible experimental conditions in the identification of low-nitrogen tolerant germplasm resources, severely restricting the progress of soybean low-nitrogen tolerance research and the development of efficient breeding technologies. Summary of the Invention

[0006] The purpose of this invention is to provide a soybean cultivation device for low-nitrogen tolerance assessment, so as to solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a soybean cultivation device for low-nitrogen tolerance assessment, comprising: The nutrient supply center is equipped with a main regulating fluid chamber and several independently arranged nutrient fluid chambers around it. Several cultivation units are arranged around the nutrient supply center, and each cultivation unit includes at least one independent culture chamber. A zoned synchronous control liquid-gas delivery system includes: Liquid delivery components: The submersible vortex forming unit generates an upward vortex at the bottom of the culture chamber through a vortex ejector; The liquid microenvironment control unit forms an aerosol in the canopy space through an ultrasonic atomizing disk; Both units share the same nutrient source but have independently regulated flow rates; Gas delivery components: A central air supply rod that runs through the entire cultivation unit; The root zone directional aeration unit and the canopy directional aeration unit, which are connected to the central air delivery rod, are located at the bottom and top of the culture chamber, respectively. Embedded sensor networks, including: A liquid storage monitoring module that is linked to the submerged vortex forming unit; An environmental monitoring module embedded in the culture chamber; When the submerged vortex forming unit is activated, it simultaneously enhances root zone aeration and inhibits canopy aeration.

[0008] According to the above technical solution, the nutrient supply center includes a coaxially mounted cylindrical body; The central chamber of the cylindrical body constitutes the main regulating liquid chamber, and five independent nutrient liquid chambers are evenly distributed around it. Each nutrient liquid chamber is physically isolated from the main regulating liquid chamber by radial partitions. The main regulating liquid chamber is connected to a detachable centralized filter cartridge via a top flange. The gas output end of the detachable centralized filter cartridge is divided into: The main gas pipeline is connected to the air inlet end of the central gas delivery rod; The auxiliary gas delivery pipeline is connected to the top of the main regulating liquid chamber; A multi-channel dynamic mixer is embedded in the main regulating liquid chamber. The spiral array nozzles of the multi-channel dynamic mixer penetrate the cylindrical body, and the inlet of the spiral array nozzles extends into the bottom liquid area of ​​the main regulating liquid chamber.

[0009] According to the above technical solution, the detachable centralized filter cartridge comprises, in sequence along the airflow direction: Removable metal filter screen; A cylindrical activated carbon adsorption layer is coated around the metal filter screen; A ring-shaped ultraviolet lamp surrounds the inlet of the auxiliary gas pipeline; The main gas pipeline is connected to the central gas delivery rod using a quick-release connector.

[0010] According to the above technical solution, the shell of each cultivation unit is in the shape of an equilateral triangular prism, and the corners are rounded. The central reflux chamber is set along the axis of the triangular prism, with its top open and connected to the collecting cone. The bottom of the collecting cone is connected to the nutrient solution chamber through a reflux pipe. Three independent culture chambers are circumferentially divided around the central reflux chamber, with an angle of 120° between adjacent culture chambers; Overflow holes are provided on the bottom sidewalls of each culture chamber, and the overflow holes are connected to the liquid inlet end of the combined reflux tank; The outlet of the combined reflux trough is vertically connected to the flow collection cone.

[0011] According to the above technical solution, a detachable mounting plate is embedded in the side wall of each culture chamber; The inner surface of the detachable mounting plate is provided with a U-shaped overlapping boss, and the opening of the U-shaped overlapping boss faces the central axis of the culture chamber; A rectangular observation window is provided in the middle of the detachable mounting plate, and an array of air holes is arranged above it; The edge of the detachable mounting plate is fitted with a magnetic sealing strip, which is attracted and engaged with the magnetic sealing frame on the side wall of the culture chamber.

[0012] According to the above technical solution, the combined reflux tank is arranged sequentially from the inlet end to the outlet end: The upward-expanding conical sedimentation section is equipped with a net at the bottom and a magnetically connected cleaning cover at the top. The side wall of the combined reflux tank is fitted with an ultraviolet sterilization lamp, and the extension direction of the ultraviolet sterilization lamp is parallel to the liquid flow path; A photocatalytic coating is applied to the inner wall of the bottom of the combined reflux tank.

[0013] According to the above technical solution, the underwater vortex forming unit includes: A first electromagnetic proportional valve connected to the nutrient solution chamber via a first connecting pipe; The outlet of the first electromagnetic proportional valve is connected to the vortex injector through the second connecting pipe. The end of the vortex injector is fixed with a guide fin assembly, and the twisting direction of the guide fin assembly is consistent with the vortex rotation direction. The liquid-based microenvironment control unit includes: The second electromagnetic proportional valve is connected to the nutrient solution chamber via a third connecting pipe. An ultrasonic atomizing disc is suspended at the top of the culture chamber, with its atomizing surface facing downwards and aligned with the canopy space. The outlet of the second electromagnetic proportional valve is connected to the ultrasonic atomizing disc via a fourth connecting pipe. The annular air curtain nozzle surrounds the ultrasonic atomizing disc, and the annular air curtain nozzle is connected to the central air delivery rod through branch pipes.

[0014] According to the above technical solution, the root zone directional aeration unit includes: An annular manifold fixed at the bottom of the culture chamber is connected to the central gas delivery rod via a fifth connecting pipe; The downward-sloping micro-orifice nozzles are evenly distributed along the circumference of the annular manifold, and the central axes of the various downward-sloping micro-orifice nozzles converge on the vertical line at the center of the culture chamber. The canopy directional aeration unit includes: The annular distributor located at the top of the culture chamber is connected to the central gas delivery rod via the sixth connecting pipe; Directional nozzles are non-uniformly distributed on the annular distributor according to the leaf sequence angle; The airflow axis of the directional nozzle is inclined at an acute angle to the horizontal plane, and all axes extend and converge in the central axis region of the culture chamber. The central gas delivery rod is synchronously connected to the root zone annular manifold and the annular distributor.

[0015] According to the above technical solution, the liquid storage monitoring module includes: Nitrogen ion selective electrode inserted into the nutrient solution chamber; An ultrasonic flow meter installed in the outlet pipeline of the main regulating liquid chamber.

[0016] According to the above technical solution, the environmental monitoring module includes: A ring-shaped electrode array embedded in the inner surface of the culture chamber; Suspended in the coronal space of the culture chamber sensor; An optical turbidimeter installed on the inner wall of the overflow orifice.

[0017] Compared with the prior art, the beneficial effects achieved by the present invention are: (1) This device achieves precise control of the multi-concentration nitrogen environment required for the identification of soybean tolerance to low nitrogen through a precise nutrient solution gradient configuration system. The main regulating liquid chamber stores high-concentration nitrogen mother liquor, and the mother liquor is quantitatively injected into each independent nutrient solution chamber through the spiral array nozzle of the multi-channel dynamic homogenizer to form a stable gradient working solution (such as 0mM, 0.5mM, 1.0mM, etc.), ensuring that the experimental conditions are repeatable and the concentration is precisely controllable, providing a reliable basis for the screening of low nitrogen tolerant germplasm.

[0018] (2) The cultivation unit adopts an equilateral triangular prism structure design. The three culture chambers are equally divided around the central reflux chamber, with an adjacent angle of 120°, forming an independent microenvironment that does not interfere with each other, achieving precise microenvironment regulation. Each culture chamber serves as a biological replication unit, which maximizes the use of limited space and ensures the statistical reliability of experimental data, significantly improving the efficiency of high-throughput experiments and avoiding the random errors of traditional single-plant experiments.

[0019] (3) The liquid vortex forming unit generates a directional upward vortex at the bottom of the culture chamber through the swirl jet and the guide fin group. Combined with the downward-sloping micro-hole nozzle of the root zone directional aeration unit (the airflow axis converges at the central vertical line), it forms a highly efficient rhizosphere dissolved oxygen environment, which significantly enhances the root system's absorption efficiency of nutrients under low nitrogen conditions, effectively simulating and strengthening the physiological response of soybeans under low nitrogen stress.

[0020] (4) The liquid microenvironment control unit generates 1-5μm nitrogen-containing aerosols to cover the canopy through an ultrasonic atomizing disc. This, combined with the canopy directional aeration unit's non-uniformly distributed directional nozzles (with airflow axes converging in the central area), achieves canopy coverage. Precise control of concentration and humidity optimizes photosynthetic efficiency while preventing high humidity from lingering on the leaf surface, inhibiting the growth of pathogens, and providing dynamic adaptability to the canopy microenvironment.

[0021] (5) Achieve independent control and intelligent linkage of liquid and gas through liquid-gas delivery system: When the liquid vortex forming unit is turned on, it simultaneously enhances root zone aeration and inhibits canopy aeration. The flow rate is independently adjusted by electromagnetic proportional valve, so that the root system and canopy environment form a collaborative response mechanism, effectively avoiding the liquid-gas interference problem in traditional devices and ensuring accurate simulation of the microenvironment under low nitrogen stress conditions.

[0022] (6) The detachable centralized filter cartridge adopts a three-stage purification structure (metal mesh primary filtration, activated carbon adsorption, and ultraviolet sterilization) to ensure the physical, chemical and biological cleanliness of the input air. The purified air is delivered to the root zone aeration system through the main air supply pipeline and the global airflow distribution is achieved through the central air supply rod, providing a sterile and pollution-free gas environment for the device and significantly reducing experimental interference factors.

[0023] (7) The combined reflux tank is equipped with a conical sedimentation section, ultraviolet sterilization lamps and photocatalytic coating to achieve multi-stage purification of overflow liquid: the sedimentation section intercepts solid particles, ultraviolet sterilization kills microorganisms, the photocatalytic coating deeply degrades organic matter, and the purified liquid returns to the central reflux chamber through the collection cone for recycling, effectively reducing nutrient solution consumption, maintaining long-term stable operation of the system, and improving the sustainability of the device.

[0024] (8) Embedded sensor network enables comprehensive environmental monitoring: nitrogen ion selective electrode monitors nutrient solution concentration in real time, and ring electrode array collects rhizosphere data. Sensors monitor canopy photosynthetic activity, optical turbidimeters analyze overflow liquid status, and monitoring data are fed back to the control system to dynamically optimize liquid and gas parameters, forming a closed-loop control mechanism to ensure that experimental conditions are always at the target state. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a first perspective view of the present invention; Figure 2 This is a second perspective view of the present invention; Figure 3 This is a first partial three-dimensional schematic diagram of the present invention; Figure 4 This is a second partial perspective view of the present invention; Figure 5 This is a third partial perspective view of the present invention; Figure 6 This is a fourth partial perspective view of the present invention; Figure 7 This is a fifth partial perspective view of the present invention; Figure 8 This is a sixth partial perspective view of the present invention; Figure 9 This is a third-dimensional schematic diagram of the seventh part of the present invention; Figure 10 This is the eighth partial perspective view of the present invention; Figure 11 This is a third-dimensional schematic diagram of the ninth part of the present invention; Figure 12 This is a three-dimensional schematic diagram of the tenth part of the present invention; In the diagram: 100 - Nutrition supply center, 101 - Cylindrical cylinder, 102 - Radial baffle, 110 - Main regulating liquid chamber, 120 - Nutrient liquid chamber, 130 - Detachable centralized filter cartridge, 131 - Main gas supply pipeline, 132 - Auxiliary gas supply pipeline, 133 - Metal filter screen, 134 - Cylindrical activated carbon adsorption layer, 135 - Annular ultraviolet lamp, 140 - Multi-channel dynamic mixer, 141 - Spiral array nozzle. 200-Cultivation Unit, 210-Cultivation Chamber, 220-Central Reflux Chamber, 221-Collection Cone, 230-Overflow Hole, 240-Combined Reflux Tank, 241-Conical Sand Settling Section, 242-Cleaning Cover, 243-UV Sterilization Lamp, 244-Photocatalytic Coating, 250-Removable Mounting Plate, 251-U-shaped Overlapping Boss, 252-Rectangular Observation Window, 253-Stomach Array, 254-Magnetic Adhesion 255 - Magnetic sealing frame; 300 - Liquid-gas delivery system; 310 - Liquid delivery assembly; 311 - Subsurface vortex forming unit; 312 - First electromagnetic proportional valve; 313 - Rotary injector; 314 - Guide fin assembly; 315 - Liquid microenvironment control unit; 316 - Ultrasonic atomizing disc; 317 - Annular air curtain nozzle; 318 - Second electromagnetic proportional valve; 320 - Gas delivery assembly; 321 - Central air delivery rod; 322 - Root zone directional aeration unit; 323 - Canopy directional aeration unit; 324 - Annular manifold; 325 - Downward-sloping microporous nozzle; 326 - Annular distributor; 327 - Directional nozzle; 400 - Embedded sensor network; 410 - Liquid storage monitoring module; 411 - Nitrogen ion selective electrode; 412 - Ultrasonic flow meter; 420 - Environmental monitoring module; 421 - Annular electrode array; 422 - Sensor, 423-Optical Turbidimeter. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see Figure 1-12 The present invention provides a technical solution: a soybean cultivation device for low-nitrogen tolerance assessment, comprising: The nutrient supply center 100 is equipped with a main regulating liquid chamber 110 and several independently arranged nutrient liquid chambers 120 around it. Several cultivation units 200 are arranged around the nutrient supply center 100, and each cultivation unit 200 includes at least one independent culture chamber 210. A zoned synchronous control liquid-gas delivery system 300 includes: Liquid delivery assembly 310: The liquid-based vortex forming unit 311 generates an upward vortex at the bottom of the culture chamber 210 through the swirling jet 313; The liquid microenvironment control unit 315 forms an aerosol in the canopy space through the ultrasonic atomizing disk 316; Both units share the same nutrient source but have independently regulated flow rates; Gas delivery assembly 320: Central air supply rod 321 that runs through the cultivation unit 200; The root zone directional aeration unit 322 and the canopy directional aeration unit 323, which are connected to the central air supply rod 321, are located at the bottom and top of the culture chamber 210, respectively. Embedded sensor network 400, including: Liquid storage monitoring module 410 linked to the submerged eddy current forming unit 311; Environmental monitoring module 420 embedded in culture chamber 210; When the liquid-submerged vortex forming unit 311 is turned on, it simultaneously enhances root zone aeration and inhibits canopy aeration. Specifically, the nutrient supply center 100 includes a cylindrical body 101 coaxially mounted; The central chamber of the cylindrical body 101 constitutes the main regulating liquid chamber 110, and five independent nutrient liquid chambers 120 are evenly distributed around it. Each nutrient liquid chamber 120 is physically isolated from the main regulating liquid chamber 110 by a radial partition 102. The top flange of the main regulating liquid chamber 110 is connected to a detachable centralized filter cartridge 130, and the gas output end of the detachable centralized filter cartridge 130 is divided into: The main gas pipeline 131 is connected to the air inlet end of the central gas delivery rod 321; The auxiliary gas supply line 132 is connected to the top of the main regulating liquid chamber 110; The main regulating liquid chamber 110 is fitted with a multi-channel dynamic homogenizer 140, and the spiral array nozzles 141 of the multi-channel dynamic homogenizer 140 penetrate the cylindrical body 101, and the inlet of the spiral array nozzles 141 extends into the bottom liquid area of ​​the main regulating liquid chamber 110. The nutrient supply center 100 is the core control hub of this device. It provides a unified and clean air source for all functional areas of the device and offers nitrogen gradient nutrient solutions of varying concentrations for multiple parallel cultivation experiments. The core structure of the nutrient supply center 100 consists of a coaxially mounted cylindrical body 101, whose internal space is rationally divided into different functional areas. The main regulating liquid chamber 110, located at the very center of the cylindrical body 101, is dedicated to storing high-concentration nitrogen regulating mother liquor. The concentrated mother liquor stored therein is the sole source of concentration for preparing low-nitrogen nutrient solutions of different gradients. The independent nutrient solution chambers 120 consist of multiple independent chambers, evenly distributed around the circumference of the main regulating liquid chamber. The number of independent nutrient solution chambers is not limited, but in this example, five are used. Each independent nutrient solution chamber 120 is responsible for storing, maintaining, and supplying a specific nitrogen concentration of basic working nutrient solution to a corresponding cultivation unit 200. They are completely isolated from each other and from the main regulating chamber 110 by radial partitions 102, ensuring that the solution concentration in each chamber is independent and stable and does not interfere with each other. The multi-channel dynamic mixer 140 accurately extracts high-concentration nitrogen regulating mother liquor from the bottom liquid area of ​​the main regulating chamber 110. According to the preset gradient concentration requirements, the control system dynamically adjusts its multiple output channels to deliver a fixed amount of mother liquor to each chamber independently. In each of the independent nutrient solution chambers 120 on the periphery, the spiral array nozzles 141 of the multi-channel dynamic mixer 140 extend into the interior of the corresponding independent nutrient solution chamber 120. During operation, the spiral array nozzles 141 forcefully inject the extracted concentrated mother liquor into the base nutrient solution of the corresponding nutrient solution chamber. Utilizing the jet kinetic energy and a specific spiral flow pattern, high-speed, efficient, and uniform mixing of the mother liquor and base solution is achieved within the nutrient solution chamber 120. This generates and maintains the required target concentration gradient working solution within each independent nutrient solution chamber 120. The detachable centralized filter cartridge 130 is responsible for primary filtration (intercepting large dust particles) and deep filtration of the external air entering the entire device. The system includes odor removal and volatile organic compound removal, as well as high-efficiency sterilization (microorganism elimination), generating clean air. The purified clean air is centrally output from the top outlet of the detachable centralized filter cartridge 130 and intelligently distributed through its two branch pipelines: Main air supply pipeline: mainly responsible for vertically transporting most of the purified air downwards, connecting to the central air supply rod that runs through all cultivation units, becoming the main channel for the device's gas supply, ultimately supplying the root zone and canopy aeration; Auxiliary air supply pipeline: introduces a portion of the purified air into the gas phase space at the top of the main regulating liquid chamber to maintain a suitable internal gas pressure balance within the chamber (such as preventing negative pressure), and has auxiliary functions for supplementing gas or positive pressure protection; Specifically, the detachable centralized filter cartridge 130 includes, in sequence along the airflow direction: Removable metal filter 133; A cylindrical activated carbon adsorption layer 134 is wrapped around the metal filter screen 133; A ring-shaped ultraviolet lamp 135 surrounds the inlet of the auxiliary gas supply pipeline 132; The main gas pipeline 131 and the central gas delivery rod 321 are connected by a quick-release connector. The ambient air first flows into the detachable centralized filter cartridge 130 for treatment. Inside the cartridge, the airflow passes through a three-stage, interconnected purification system along a predetermined path. The detachable metal filter 133 serves as the first barrier in the air purification process. As the airflow passes through, the precisely woven metal filter, relying on its mesh physical barrier effect, efficiently intercepts and captures larger suspended particles in the air, such as dust, fibers, pollen, and some insects or plant debris, significantly reducing the content of coarse impurities. After this initial filtration, the air continues to flow outwards. Surrounding the metal filter 133 is a cylindrical activated carbon adsorption layer 134. When the airflow passes through the activated carbon layer, it is filtered through the intermolecular... Adsorption capacity effectively adsorbs various gaseous pollutants remaining in the air, significantly improving the chemical cleanliness of the air. Before the airflow enters the core distribution pipeline, there is a ring-shaped array of ultraviolet lamps 135. These lamps emit short-wave ultraviolet rays (such as UVC) of a specific wavelength. When the purified airflow passes through and is continuously exposed to this surrounding ultraviolet radiation field, the ultraviolet light can effectively destroy the DNA or RNA structure of microorganisms (such as bacteria, fungi, and viruses), causing them to become inactive or die. This achieves broad-spectrum killing of microorganisms in the air, ensuring the biological safety of the gas. The three-stage purification linkage ensures that the output air after this process has high physical cleanliness, low levels of chemical pollutants, and extremely low microbial load. Specifically, the shell of each cultivation unit 200 is in the shape of an equilateral triangular prism, and the corners are rounded. The central reflux chamber 220 is arranged along the axis of the triangular prism, and its top is open to connect to the collecting cone 221; Three independent culture chambers 210 are circumferentially divided around the central reflux chamber 220, and the angle between adjacent culture chambers 210 is 120°. Each culture chamber 210 has an overflow hole 230 on its bottom side wall, and the overflow hole 230 is connected to the liquid inlet end of the combined reflux tank 240; The outlet of the combined reflux trough 240 is vertically connected to the collecting cone 221, and the bottom of the collecting cone 221 is connected to the nutrient solution chamber 120 through a reflux pipeline. The outer shell of the cultivation unit 200 adopts an equilateral triangular prism structure with rounded corners. This triangular prism structure maximizes the volume of the cultivation chamber within a limited space, improving space utilization efficiency. The rounded corners prevent scratches and enhance safety. The central reflux chamber 220 is located along the central axis of the triangular prism shell, with an open top interface firmly connected to the collecting cone 221. This serves as a collection and transfer hub for the purified liquid, receiving the purified overflow from each cultivation chamber 120 and guiding it to the circulation system. The three cultivation chambers 210 are evenly arranged circumferentially around the central reflux chamber 220, with adjacent chamber axes forming an angle of 120 degrees. Each chamber constitutes an independent plant cultivation microenvironment, capable of accommodating a single large plant. The bean and its root cap system physically isolate different plants to avoid cross-interference. The three independent culture chambers are biological replicas of each other, and the plants are cultured synchronously under the same nitrogen concentration to ensure the reliability of experimental data. The overflow hole 230 is opened at a specific height on the bottom side wall of each culture chamber 210. When the nutrient solution level in the culture chamber 210 exceeds the set height, the excess liquid is automatically discharged through the overflow hole 230. The combined return channel 240 is located on the outer side wall of the culture chamber 210. Each combined return channel 240 corresponds to one culture chamber 210, forming an independent overflow space to avoid cross-interference. Its inlet end is directly connected to the overflow hole 230, and the outlet extends vertically downward and is precisely connected to the top of the collecting cone 221. Specifically, each culture chamber 210 has a detachable mounting plate 250 embedded in its sidewall; The inner surface of the detachable mounting plate 250 is provided with a U-shaped overlapping boss 251, and the opening of the U-shaped overlapping boss 251 faces the central axis of the culture chamber 210; A rectangular observation window 252 is provided in the middle of the detachable mounting plate 250, and an array of air holes 253 is arranged above it. A magnetic sealing strip 254 is embedded in the edge of the detachable mounting plate 250, and the magnetic sealing strip 254 is attracted and engaged with the magnetic sealing frame 255 on the side wall of the culture chamber 210. The U-shaped overlapping protrusion 251 has its opening strictly facing the central axis of the culture chamber 210. Its U-shaped structure forms an adaptive clamping groove. During sowing, the hypocotyl part of the soybean seed is embedded in the U-shaped groove to ensure that the seedling grows vertically. The rectangular observation window 252 supports daily visual inspection of root development, nutrient solution turbidity, and other conditions. The stomatal array 253 is densely distributed in the area above the rectangular observation window 252 to construct a gas exchange channel for the canopy aerosol microenvironment, balance the air pressure inside and outside the chamber, and allow gas permeation while blocking droplet escape to prevent aerosol diffusion and contamination of adjacent units. The mounting plate has a pre-embedded magnetic sealing strip 254, which, together with the magnetic sealing frame 255 on the side wall of the culture chamber 210, forms an adsorption sealing surface. The magnetic force uniformly compresses the sealing strip to block the leakage of nutrient solution and the intrusion of external pollutants. Specifically, the combined reflux tank 240 is arranged sequentially from the inlet end to the outlet end: The upwardly flared conical sedimentation section 241 has an interception net at the bottom and a magnetically connected cleaning cover 242 at the top. The side wall of the combined reflux tank 240 is fitted with an ultraviolet sterilization lamp tube 243, and the ultraviolet sterilization lamp tube 243 extends in a direction parallel to the liquid flow path; A photocatalytic coating 244 is provided on the inner bottom wall of the combined reflux tank 240; The combined reflux tank is a directional purification and collection channel for overflow liquid. The liquid flow direction strictly follows: overflow liquid inlet, conical sand settling section 241 contraction channel, bottom interception net interception, ultraviolet sterilization lamp tube 243 rapid sterilization, photocatalytic deep degradation, collection cone outlet 221 discharge. The cross-section of the conical sand settling section 241 gradually contracts towards the outlet direction to form an accelerating flow channel. The overflow inlet is located on the middle side wall of the conical sand settling section 241. The liquid is injected tangentially into the sand settling section, accelerating the water flow to drive impurities (mud, root debris, condensate) to the bottom of the sand settling section. The magnetic cleaning cover plate 242 covers the top of the conical sand settling section 241 for easy disassembly and removal of silt. Specifically, the underwater vortex forming unit 311 includes: The first electromagnetic proportional valve 312 is connected to the nutrient solution chamber 120 via the first connecting pipe; The outlet of the first electromagnetic proportional valve 312 is connected to the vortex injector 313 through the second connecting pipe. The end of the vortex injector 313 is fixed with the guide fin assembly 314. The twisting direction of the guide fin assembly 314 is consistent with the vortex rotation direction. The liquid microenvironment control unit 315 includes: The second electromagnetic proportional valve 318 is connected to the nutrient solution chamber 120 via a third connecting pipe; The ultrasonic atomizing disc 316, suspended at the top of the culture chamber 210, has its atomizing surface facing downwards and aligned with the canopy space. The outlet of the second electromagnetic proportional valve 318 is connected to the ultrasonic atomizing disc 316 through the fourth connecting pipe. An annular air curtain nozzle 317 surrounds the ultrasonic atomizing disc 316, and the annular air curtain nozzle 317 is connected to the central air supply rod 321 through a branch pipeline. The subsurface vortex forming unit 311 generates a directional rotating liquid flow at the bottom of the culture chamber 210, realizing dynamic control of the root microenvironment. The first electromagnetic proportional valve 312 receives commands from the control system and dynamically adjusts the liquid flow rate from the nutrient solution chamber 120. A delivery pump is installed on the connecting pipe to provide basic delivery pressure. The delivery pump and the fixing seat for the fixed connecting pipe (not shown in the figure) are well-known technologies in the prior art and can be adjusted according to the actual application scenario. They will not be described in detail here. The liquid is accelerated by the spiral flow channel of the vortex ejector 313 and transformed into a high-speed rotating jet. The guide fin assembly 314 is fixed at the end of the flow channel with a preset torsion angle. The curved surface of the fins continuously guides the rotation direction of the liquid flow, expanding the vortex coverage to the entire root region. The subsurface microenvironment control unit 315 establishes a dual-mode of aerosol and gas at the top of the culture chamber 210. The control field precisely manages the canopy microenvironment. The second electromagnetic proportional valve 318 accurately controls the nutrient solution supply. The ultrasonic atomizing disc 316 is suspended at the top center of the culture chamber 210, occupying the upper layer of the canopy space. The atomization direction is vertically downward, converting the liquid into 1-5μm droplets. The annular air curtain nozzle 317 forms a vertically downward isolation air curtain around the edge of the atomizing disc 316 to block the lateral diffusion of aerosols and to help isolate gas exchange between different culture units. The dual barrier of the air curtain and the physical sealing structure ensures zero cross-contamination between the 15 culture units. It shares the air path with the canopy directional aeration unit 323, and the concentration is adjusted by switching valves. The two units share the nutrient solution supply chamber 120, reducing redundant pipelines and supporting independent or linked operation modes (e.g., aerosol supplementation above the liquid during the day and vortex oxygenation below the liquid at night). Specifically, the root zone directional aeration unit 322 includes: The annular manifold 324, fixed to the bottom of the culture chamber 210, is connected to the central gas delivery rod 321 via the fifth connecting pipe; The downward-sloping micro-orifice nozzles 325 are evenly distributed around the annular manifold 324, and the central axes of each downward-sloping micro-orifice nozzle 325 converge on the central vertical line of the culture chamber 210. The canopy directional aeration unit 323 includes: The annular distributor 326, located at the top of the culture chamber 210, is connected to the central gas delivery rod 321 via a sixth connecting pipe. The directional nozzles 327 are non-uniformly distributed on the annular distributor 326 according to the leaf sequence angle; The airflow axis of the directional nozzle 327 is inclined at an acute angle to the horizontal plane, and all axes extend and converge in the central axis region of the culture chamber 210; The central gas delivery rod 321 is synchronously connected to the root zone annular manifold 324 and the annular distributor 326. The root zone directional aeration unit 322 constructs a uniform dissolved oxygen field in the dense root zone. A ring manifold 324 is fixed to the bottom of the culture chamber 210 and connected to the central air delivery rod 321 via a fifth connecting pipe. Slanted downward micro-orifice nozzles 325 are evenly distributed around the ring manifold 324, forming a ring-shaped high-pressure air chamber surrounding the roots. The central axes of all nozzles precisely intersect the vertical line at the center of the culture chamber. The airflow is sprayed downwards at a 45° angle, pushing the bubble clusters spirally towards the center of the root system. The upward path of the bubbles is extended, increasing the gas-liquid contact time. The canopy directional aeration unit 323 regulates the canopy gas composition and micro-airflow field to match the plant's photosynthetic needs. A ring distributor 326 is suspended at the top of the chamber and connected to the central air delivery rod 321 via a sixth connecting pipe. Directional nozzles 327 are non-uniformly distributed according to the plant's leaf angle. Each nozzle independently adjusts the airflow angle. All airflow axes extend and converge in the central axis area of ​​the canopy. The airflow is sprayed at a 15° acute angle, forming a conical air curtain enveloping each plant for precise delivery. To the densely populated stomatal area, to prevent high humidity gas from lingering on the leaf surface and inhibit the growth of pathogens, a single air path simultaneously supplies air to the root zone annular manifold 324 and the canopy annular distributor 326. The ratio of airflow in the root zone and the canopy is adjusted as needed by the control valve. For example, in daytime mode, the canopy airflow is stronger than the root airflow to enhance photosynthetic gas exchange, while in nighttime mode, the canopy airflow is weaker than the root airflow to enhance root metabolic efficiency. Through multi-level coordinated control of the liquid delivery component 310 and the gas delivery component 320, precise regulation of the three-dimensional environment from the root system to the canopy is achieved. The specific coordinated mechanism is as follows: I. Dynamic Coupling Mechanism of Liquid-Gas in the Root Region When the submerged vortex forming unit 311 is started, the first electromagnetic proportional valve 312 controls the nutrient solution to be sprayed into the bottom of the culture chamber through the vortex injector. The guide fin group 314 guides the nutrient solution to form an upward spiral vortex. At this time, the root zone directional aeration unit 322 of the gas delivery component is activated simultaneously. The central gas delivery rod 321 delivers gas to the annular manifold 324. The downward-sloping micro-orifice nozzle 325 injects microbubbles along the vortex rotation direction. The bubble group is broken and refined by the vortex shearing action, forming a gas-liquid two-phase spiral flow rotating in the same direction with the upward liquid flow, which improves the dissolved oxygen mass transfer efficiency. The axial convergence design of the downward-sloping micro-orifice nozzle 325 ensures that the bubbles are enriched in the root core area.

[0028] II. Co-control Mechanism of Canopy Aerosol When the liquid microenvironment control unit 315 is running, the second electromagnetic proportional valve 318 delivers nutrient solution to the ultrasonic atomizing disk 316, generating aerosols in the canopy space. At the same time, the gas delivery component 320 initiates two-stage coordination: the annular air curtain nozzle 317 draws air from the central air delivery rod 321 through branch pipes, forming a vertically downward annular air curtain barrier around the ultrasonic atomizing disk 316. This air curtain restricts the aerosol diffusion range and prolongs the droplet settling time. The annular distributor 326 of the canopy directional aeration unit 323 receives the gas diverted from the central air delivery rod 321, and its non-uniformly arranged directional nozzles 327 deliver inclined airflow to the blade area, pushing the aerosols to be directionally enriched in the dense stomata area of ​​the blades, improving the effective utilization rate.

[0029] III. Root-crown synergistic control logic Using root zone priority control logic, when the submerged vortex forming unit 311 is turned on, the controller automatically increases the air supply pressure of the root zone directional aeration unit 322 to the peak value, and at the same time switches the canopy directional aeration unit 323 to the minimum maintenance flow rate. When the liquid surface microenvironment control unit 315 is working, the root zone directional aeration maintains the basic aeration volume, and the canopy directional nozzle 327 is adjusted to pulse jet mode to avoid strong airflow disturbance to the atomization field, ensuring that the root dissolved oxygen concentration fluctuation is within the threshold range and improving the stability of canopy aerosol concentration.

[0030] When the environmental monitoring module 420 detects abnormal rhizosphere conductivity, the system automatically increases the submerged eddy current flow rate and simultaneously enhances root zone aeration to alleviate ion imbalance. The sensor showed a decrease in canopy carbon assimilation efficiency. The ultrasonic atomizing disc 316 switched to intermittent mode and started the strong circulation mode of the canopy directional nozzle to shorten the soybean's response time to low nitrogen stress and ensure the microenvironmental homeostasis throughout the growth period.

[0031] Specifically, the liquid storage monitoring module 410 includes: Nitrogen ion selective electrode 411 is inserted into nutrient solution chamber 120; Ultrasonic flow meter 412 is installed in the outlet pipeline of the main regulating liquid chamber 110; The electrode probe is directly immersed in the nutrient solution chamber 120. It senses the change in nitrogen ion concentration in real time through the ion-selective membrane and converts it into an electrical signal output. The ultrasonic flow meter 412 monitors the nutrient solution infusion rate and identifies pipeline blockage or leakage abnormalities. Specifically, the environmental monitoring module 420 includes: A ring electrode array 421 is embedded in the inner surface of the culture chamber 210; Suspended in the coronal space of culture chamber 210 Sensor 422; An optical turbidimeter 423 is installed on the inner wall of the overflow orifice 230; The annular electrode array 421 is embedded in the inner surface of the removable mounting plate 250, with the electrode contacts directly exposed inside the culture chamber 210. The circumferentially distributed contacts cover the entire root region boundary. Sensor 422 is positioned in the densest area of ​​the leaves to directly capture the photosynthetic active zone. Concentration gradient, real-time sampling analysis The concentration change rate is correlated with light intensity data to calculate net photosynthetic efficiency. The optical turbidimeter 423 is embedded in the inner wall of the overflow hole 230, directly contacting the discharged liquid and capturing abnormal substances into the circulation system in the first instance.

[0032] Working principle: This device provides a highly controllable, multi-gradient parallel, and precisely adjustable high-throughput culture platform for the identification of soybean germplasm resources tolerant to low nitrogen. Its core lies in the dynamic configuration of multiple nutrient concentrations through a central mother liquor, combined with root zone and canopy zone control and closed-loop monitoring, to accurately simulate low nitrogen stress conditions of varying intensities. The main workflow of this device is as follows: I. Nutrient solution gradient configuration Mother liquor storage: The main regulating liquid chamber 110 stores high-concentration nitrogen regulating mother liquor (such as potassium nitrate concentrate) as the core nitrogen source for gradient regulation.

[0033] Base solution pre-filling: Multiple independent nutrient solution chambers 120 surrounding the main regulating liquid chamber 110 are pre-filled with nitrogen-free or very low nitrogen base nutrient solution (containing all essential elements except nitrogen).

[0034] Dynamic gradient generation: The multi-channel dynamic homogenizer 140 draws mother liquor from the main regulating liquid chamber 110 and injects it quantitatively into each independent nutrient liquid chamber 120 through the spiral array nozzle 141. According to the target nitrogen concentration (such as 0mM, 0.5mM, 1.0mM, etc.), the control system adjusts the amount of mother liquor injected, and after mixing, a multi-gradient stable working solution is formed.

[0035] II. Irrigation and Root Zone Regulation in Cultivation Units Nutrient solution delivery in the root zone: Each independent nutrient solution chamber 120 is connected to the corresponding cultivation unit 200 through pipelines. The first electromagnetic proportional valve 312 regulates the flow rate. The nutrient solution forms an upward vortex at the bottom of the cultivation chamber 210 through the vortex injector 313 and the guide fins 314, which forcibly agitates the liquid flow, prevents sedimentation, and enhances dissolved oxygen.

[0036] Root zone directional aeration: The centralized detachable filter cartridge 130 purifies the external air and delivers it to the root zone directional aeration unit 322 through the central air delivery rod 321. The downward-sloping micro-hole nozzles 325 spray airflow directionally to the dense root area, supplying high concentrations of oxygen and optimizing the rhizosphere environment in conjunction with vortex.

[0037] III. Regulation of the Canopy Microenvironment Leaf nutrient atomization: The second electromagnetic proportional valve 318 regulates the flow rate, and the liquid in the same nutrient solution chamber is delivered to the ultrasonic atomizing plate 316 to generate nitrogen-containing aerosol to cover the canopy and simulate the leaf absorption scenario.

[0038] Canopy airflow control: Purified air is delivered to the canopy directional aeration unit 323 via the central air delivery bar 321. Directional nozzles 327 are distributed according to the leaf sequence angle, obliquely spraying airflow to the center of the canopy. Adjustment... Concentration, humidity, and aerosol diffusion are all factors that contribute to aerosol diffusion.

[0039] When the submerged vortex is activated, it enhances the aeration rate in the root zone while suppressing canopy airflow to reduce disturbance.

[0040] IV. Environmental Closed-Loop Monitoring and Feedback Storage liquid status monitoring: Nitrogen ion selective electrode 411 monitors the concentration of nutrient solution in nutrient solution chamber 120 in real time, ultrasonic flow meter 412 detects the outlet flow of each nutrient solution chamber, and feedback adjusts the opening of electromagnetic proportional valve.

[0041] Culture chamber environment monitoring: A ring electrode array 421 monitors rhizosphere pH, EC, and temperature, reflecting root activity. Sensor 422 collects canopy gas data, optical turbidimeter 423 detects the cleanliness of overflow liquid, and the data is fed back to the control system to optimize liquid and gas parameters.

[0042] V. Overflow Recovery and Purification Overflow collection: Excess nutrient solution in the culture chamber flows into the combined return tank 240 through the overflow hole 230, and undergoes multiple purification stages: Sand settling treatment: Conical sand settling section 241 intercepts solid particles, and magnetic cover plate 242 facilitates cleaning; Ultraviolet sterilization: Ultraviolet lamp tube 243 kills microorganisms; Photocatalytic degradation: Photocatalytic coating 244 decomposes organic matter under ultraviolet excitation.

[0043] Recycling: The purified liquid flows into the central return chamber 220 through the collecting cone 221 and returns to the original nutrient solution chamber 120 for recycling.

[0044] VI. Overall Air Purification Primary filtration: External air passes through metal filter 133 to intercept large particulate impurities.

[0045] Adsorption and purification: Activated carbon layer 134 removes odors and harmful gases.

[0046] UV sterilization: 135°C ring-shaped UV lamps inactivate microorganisms, and clean air is delivered to the root zone and canopy aeration system.

[0047] VII. High-throughput experiments and data applications Multi-gradient parallel processing: Multiple independent nutrient solution chambers 120 correspond one-to-one with cultivation units 200, supporting the simultaneous conduct of stress experiments with different nitrogen concentrations (5 gradients in the example), with each group containing 3 culture chambers as biological replicates.

[0048] Data-driven analysis: Real-time monitoring of data (nitrogen concentration, root activity, canopy) (e.g., turbidity) is used to assess soybean tolerance, screen for low-nitrogen tolerant germplasm, and optimize cultivation strategies.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0050] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A soybean cultivation device for low-nitrogen tolerance assessment, characterized in that, include: The nutrient supply center (100) is provided with a main regulating fluid chamber (110) and several independently arranged nutrient fluid chambers (120) around it. Several cultivation units (200) are arranged around the nutrient supply center (100), and each cultivation unit (200) includes at least one independent culture chamber (210). A zoned synchronous control liquid-gas delivery system (300) includes: Liquid delivery assembly (310): The submerged vortex forming unit (311) generates an upward vortex at the bottom of the culture chamber (210) through a vortex ejector (313); The liquid microenvironment control unit (315) forms an aerosol in the canopy space through the ultrasonic atomizing disk (316); Both units share the same nutrient source but have independently regulated flow rates; Gas delivery assembly (320): Central air supply bar (321) that runs through the cultivation unit (200); The root zone directional aeration unit (322) and the canopy directional aeration unit (323), which are connected to the central air delivery rod (321), are located at the bottom and top of the culture chamber (210), respectively. Embedded sensor network (400), including: Liquid storage monitoring module (410) linked with the liquid vortex forming unit (311). An environmental monitoring module (420) is embedded in the culture chamber (210); When the submerged vortex forming unit (311) is turned on, it simultaneously enhances root zone aeration and inhibits canopy aeration.

2. The apparatus according to claim 1, characterized in that: The nutrient supply center (100) includes a coaxially mounted cylindrical body (101). The central chamber of the cylindrical body (101) constitutes the main regulating liquid chamber (110), and five independent nutrient liquid chambers (120) are evenly distributed around it. Each nutrient liquid chamber (120) is physically isolated from the main regulating liquid chamber (110) by a radial partition (102). The top flange of the main regulating liquid chamber (110) is connected to a detachable centralized filter cartridge (130), and the gas output end of the detachable centralized filter cartridge (130) is divided into: The main gas pipeline (131) is connected to the inlet end of the central gas delivery rod (321); The auxiliary gas delivery pipeline (132) is connected to the top of the main regulating liquid chamber (110); The main regulating liquid chamber (110) is fitted with a multi-channel dynamic homogenizer (140), and the spiral array nozzles (141) of the multi-channel dynamic homogenizer (140) penetrate the cylindrical body (101), and the inlet of the spiral array nozzles (141) extends into the bottom liquid area of ​​the main regulating liquid chamber (110).

3. The apparatus according to claim 2, characterized in that: The detachable centralized filter cartridge (130) comprises, in sequence along the airflow direction: Removable metal filter (133); A cylindrical activated carbon adsorption layer (134) is wrapped around the metal filter screen (133); A ring-shaped ultraviolet lamp (135) surrounds the inlet of the auxiliary gas supply pipeline (132); The main gas pipeline (131) and the central gas delivery rod (321) are connected by a quick-release connector.

4. The apparatus according to claim 1, characterized in that: Each cultivation unit (200) has an equilateral triangular prism shell with rounded corners at the edges; The central reflux chamber (220) is set along the axis of the triangular prism, and its top is open to connect to the collecting cone (221). Three independent culture chambers (210) are circumferentially divided around the central reflux chamber (220), and the included angle between adjacent culture chambers (210) is 120°; Each culture chamber (210) has an overflow hole (230) on its bottom sidewall, and the overflow hole (230) is connected to the liquid inlet end of the combined reflux tank (240); The outlet of the combined reflux trough (240) is vertically connected to the collecting cone (221), and the bottom of the collecting cone (221) is connected to the nutrient solution chamber (120) through a reflux pipeline.

5. The apparatus according to claim 4, characterized in that: Each culture chamber (210) has a removable mounting plate (250) embedded in its sidewall; The inner surface of the detachable mounting plate (250) is provided with a U-shaped overlapping boss (251), and the opening of the U-shaped overlapping boss (251) faces the central axis of the culture chamber (210); A rectangular observation window (252) is provided in the middle of the detachable mounting plate (250), and an array of air holes (253) is arranged above it; The edge of the detachable mounting plate (250) is fitted with a magnetic sealing strip (254), which is attracted to the magnetic sealing frame (255) on the side wall of the culture chamber (210).

6. The apparatus according to claim 4, characterized in that: The combined reflux tank (240) is arranged sequentially from the inlet end to the outlet end: The upward-expanding conical sedimentation section (241) has an interception net at the bottom and a cleaning cover plate (242) with magnetic connection at the top. The side wall of the combined reflux tank (240) is fitted with an ultraviolet sterilization lamp (243), and the ultraviolet sterilization lamp (243) extends in a direction parallel to the liquid flow path; A photocatalytic coating (244) is provided on the inner wall of the bottom of the combined reflux tank (240).

7. The apparatus according to claim 1, characterized in that: The underwater vortex forming unit (311) includes: The first electromagnetic proportional valve (312) is connected to the nutrient solution chamber (120) via the first connecting pipe. The outlet of the first electromagnetic proportional valve (312) is connected to the vortex injector (313) through the second connecting pipe. The end of the vortex injector (313) is fixed with a guide fin assembly (314). The twisting direction of the guide fin assembly (314) is consistent with the vortex rotation direction. The liquid-based microenvironment control unit (315) includes: The second electromagnetic proportional valve (318) is connected to the nutrient solution chamber (120) via the third connecting pipe. The ultrasonic atomizing disc (316) suspended at the top of the culture chamber (210) has its atomizing surface facing downwards and aligned with the canopy space. The outlet of the second electromagnetic proportional valve (318) is connected to the ultrasonic atomizing disc (316) through the fourth connecting pipe. An annular air curtain nozzle (317) surrounds the ultrasonic atomizing disc (316), and the annular air curtain nozzle (317) is connected to the central air delivery rod (321) through a branch pipeline.

8. The apparatus according to claim 7, characterized in that: The root zone directional aeration unit (322) includes: The annular manifold (324) fixed at the bottom of the culture chamber (210) is connected to the central gas delivery rod (321) through the fifth connecting pipe. The downward-sloping micro-orifice nozzles (325) are evenly distributed around the annular manifold (324), and the central axes of each downward-sloping micro-orifice nozzle (325) converge on the central vertical line of the culture chamber (210). The canopy directional aeration unit (323) includes: The annular distributor (326) located at the top of the culture chamber (210) is connected to the central gas delivery rod (321) via the sixth connecting pipe. The directional nozzles (327) are non-uniformly distributed on the annular distributor (326) according to the leaf sequence angle. The airflow axis of the directional nozzle (327) is inclined at an acute angle to the horizontal plane, and all axes extend and converge in the central axis region of the culture chamber (210); The central gas delivery rod (321) is synchronously connected to the root zone annular manifold (324) and the annular distributor (326).

9. The apparatus according to claim 2, characterized in that: The liquid storage monitoring module (410) includes: Nitrogen ion selective electrode (411) inserted into nutrient solution chamber (120); An ultrasonic flow meter (412) is installed in the outlet pipe of the main regulating liquid chamber (110).

10. The apparatus according to claim 4, characterized in that: The environmental monitoring module (420) includes: A ring electrode array (421) is embedded in the inner surface of the culture chamber (210). Suspended in the canopy space of the culture chamber (210) Sensor (422); An optical turbidimeter (423) is installed on the inner wall of the overflow hole (230).

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