Pine seedling raising method and device based on temperature gradient and photoperiod coordinated regulation and control

Abstract

The invention discloses a pine seedling raising method and device based on temperature gradient and photoperiod coordinated regulation, and the method comprises the following steps: S1, seed source molecular marker-assisted screening: in a pine natural distribution area, collecting healthy excellent tree species with the tree age of more than or equal to 30 years, the fruiting amount interannual variation coefficient of less than 15%, and no pest or disease damage; high-grease seed sources are screened through a molecular marker technology, pretreatment with compound liquid is combined, and temperature-light synergistic regulation and control of three-temperature-zone gradient and precise spectrum are matched, so that the seed germination rate is effectively increased, and the quality stability of the pine is enhanced; a composite frozen soil defense structure is matched with an internet-of-things intelligent heating system, so that targeted protection of freezing injury of pine root systems is realized, and meanwhile, energy consumption is effectively reduced; through accurate temperature and light regulation and control of the closed seedling raising cabin and dynamic management of the ad hoc network, the defect of insufficient accumulated temperature in a cold region is overcome, and the limitation of short growing season is broken through, so that the growth efficiency of the pine is effectively improved.

Description

Technical Field

[0001] This application relates to the technical field of dwarf pine seedling cultivation, and in particular to a method and apparatus for dwarf pine seedling cultivation based on the coordinated regulation of temperature gradient and photoperiod. Background Technology

[0002] As a woody oilseed tree species unique to cold and temperate zones, the kernels of *Pinus dactylon* have a high oil content and an extremely high proportion of unsaturated fatty acids, making them an important raw material for high-end edible oils and biodiesel. However, traditional seedling cultivation methods for *Pinus dactylon* in cold regions have the following drawbacks: First, the germination rate of cold-resistant dwarf pine after conventional stratification treatment is low, and the oil content of seedlings varies greatly and is not stable enough. Existing seedling methods rely solely on natural climate to break seed dormancy, which neither improves the basic germination rate nor addresses the problem of oil content variation.

[0003] Secondly, in the extreme low temperatures of cold regions, traditional soil covering for frost protection is ineffective, resulting in a persistently high mortality rate for seedlings overwintering. While existing technologies attempt to regulate temperature through heating wires, these methods are not only extremely energy-intensive but also lack optimized protection against root frost damage in cold regions, resulting in insufficient frost resistance. Furthermore, the short growing season and insufficient accumulated temperature in cold regions lead to low annual growth and slow growth of dwarf pine, and existing technologies, relying on natural light and temperature conditions, struggle to overcome this growth lag bottleneck. Application content

[0004] This application aims to at least partially address one of the technical problems in the related art.

[0005] To achieve the above objectives, this application proposes a method for cultivating *Pinus sylvestris* seedlings based on the synergistic regulation of temperature gradient and photoperiod, comprising the following steps: S1, marker-assisted screening of seed source: In the natural distribution area of ​​Pinus sylvestris, collect superior tree germplasm with an age of ≥30 years, an interannual coefficient of variation of fruit yield <15%, and good health free from pests and diseases; use SSR molecular marker technology to screen the superior tree germplasm for PIN genotype, and screen and determine the genotype mother plants with an oil content of ≥50% as seed source donors. S2, Temperature-Photosynergistic Germination Regulation: Seeds from the aforementioned seed donor were soaked in a compound solution of 0.2% gibberellin and 0.1% salicylic acid and treated at 4℃±0.5℃ for 48 hours; subsequently, the seeds were transferred to a programmable light-temperature chamber and subjected to a three-temperature gradient germination regulation program. Phase I (0-15 days): Day / night temperature is 18℃ / 5℃, red light with wavelength of 660nm is used for irradiation for 12 hours / day, and light intensity is 80μmol·m⁻²·s⁻¹; Phase II (16-30 days): Day / night temperature is 10℃ / -2℃, blue light with wavelength of 450nm is used for irradiation for 8 hours / day, and UV-B irradiation of 2.8W / m² is supplemented for 1 hour / day. Phase III (31-45 days): Implement a temperature gradient change from -5℃ to 8℃ at a rate of 0.5℃ / h and at a uniform rate, using full-spectrum irradiation for 6 hours / day; S3, Frozen Soil Defense Structure Planting: Select a sunny slope with a gradient of ≤10°, and dig planting holes with dimensions of 60cm×60cm×50cm. The planting holes adopt a three-layer composite frozen soil defense structure, with each layer from bottom to top as follows: Bottom layer: A 15cm thick layer of basalt gravel is laid, the basalt gravel having a particle size of 3-5cm and being mixed with 5% biochar by mass. Middle layer: A 30cm thick mixed substrate is laid, which is composed of humus, peat and vermiculite in a volume ratio of 5:3:2, with a pH value of 5.0–6.0; Surface layer: A 10cm thick moss layer is laid, in which 15% by mass of phase change microcapsules are mixed. The phase change microcapsules are a composite of paraffin and expanded graphite, with a phase change point of -8℃ and a latent heat of phase change ≥210J / g. S4, IoT dynamic management: Each group consists of 5 seedlings, and each group is equipped with one multi-parameter sensor node; the sensor node includes a root temperature probe and an FDR moisture content sensor, wherein the root temperature probe is buried at a depth of 25cm and the FDR moisture content sensor is buried at a depth of 15cm. Establish a LoRa self-organizing network with a transmission distance of ≥3km to monitor root zone temperature and soil conductivity data in real time. When the root zone temperature T so ᵢ l When the temperature is below -5℃, the carbon crystal heating plate of the corresponding planting hole will be automatically activated. The power of the carbon crystal heating plate is 120W / hole. When the soil electrical conductivity EC is greater than 1.5mS / cm, the drip irrigation system will be automatically triggered to perform salt leaching. The leaching flow rate of the drip irrigation system is 8L / min.

[0006] Specifically, the phase change microcapsules in step S3 are core-shell composite structures, prepared by combining a paraffin core and an expanded graphite shell; the latent heat of phase change of the paraffin core is ≥180J / g, the porosity of the expanded graphite shell is 92%, and the amount of phase change microcapsules incorporated into the surface moss is 15% of the dry weight of the moss.

[0007] Specifically, the programmable light and temperature box in step S2 has a built-in height-adjustable LED light source frame. The height of the LED light source frame is adaptively adjustable within a range of 20–50 cm. Through height adaptive adjustment, the spatial variation coefficient of light intensity in the seedling area is ensured to be <5%.

[0008] A seedling cultivation device for Pinus tabuliformis based on the coordinated regulation of temperature gradient and photoperiod includes a temperature and photoperiod coordinated regulation unit, a permafrost defense structure unit, and an Internet of Things management unit. The temperature and light synergistic control unit includes a sealed seedling chamber with external dimensions of 2.5m × 2.0m × 2.0m. The seedling chamber is divided into three independent temperature control zones by partitions. An LED light source matrix is ​​installed in the seedling chamber. The temperature control range of the independent temperature control zones is -10℃ to 25℃, with a control accuracy of ±0.3℃. The LED light source matrix supports three-channel switching: red light 660nm, blue light 450nm, and full spectrum. The permafrost defense structural unit includes a honeycomb ceramic matrix with a pore size of 5 mm and filled with phase change microcapsules. The surface of the honeycomb ceramic matrix is ​​covered with a breathable non-woven fabric with a basis weight of 80 g / m². The IoT management unit includes a dual-band soil radar and an edge computing gateway. The dual-band soil radar operates at a frequency of 1GHz / 250MHz and is used to scan the depth of the frozen soil layer in the seedling area in real time. The edge computing gateway pre-stores a heating control strategy. The power calculation formula for the control strategy is: P=K1·e^(0.2ΔT), where ΔT is the difference between the set temperature and the measured temperature in the root zone, the coefficient K1=50W / ℃, and P is the heating power.

[0009] The beneficial effects of the method and device for cultivating dwarf pine seedlings based on the synergistic regulation of temperature gradient and photoperiod in this application are as follows: 1. By screening high-oil seed sources using molecular marker technology, combined with pretreatment with compound solution, and with temperature and light synergistic regulation using a three-temperature gradient and precise spectrum, not only is the seed germination rate effectively improved, but the quality stability of dwarf pine is also enhanced. 2. A composite frozen soil protection structure combined with an IoT-based intelligent heating system is adopted to achieve targeted protection against frost damage to the roots of creeping pine, while effectively reducing energy consumption; 3. By precisely controlling the temperature and light in the closed seedling chamber and dynamically managing the self-organizing network, the insufficient accumulated temperature in cold regions is compensated for, and the limitation of the short growing season is overcome, thereby effectively improving the growth efficiency of dwarf pine. Attached Figure Description

[0010] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart illustrating the process of this application; Figure 2 This is a schematic diagram of the germination regulation of the three-temperature gradient in this application; Figure 3 This is a cross-sectional view of the seedling chamber of this application.

[0011] As shown in the figure: 1. Seedling chamber; 2. Partition; 3. LED light source matrix. Detailed Implementation

[0012] To make the technical means, inventive features, objectives, and effects of this application easier to understand, the application is further described below with reference to specific illustrations. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0013] like Figure 1 and Figure 2 As shown in the figure, a method for cultivating *Pinus sylvestris* seedlings based on the synergistic regulation of temperature gradient and photoperiod according to an embodiment of this application includes the following steps: S1, marker-assisted screening of seed source: In the natural distribution area of ​​Pinus sylvestris, collect superior tree germplasm with an age of ≥30 years, an interannual coefficient of variation of fruit yield <15%, and good health free from pests and diseases; use SSR molecular marker technology to screen the superior tree germplasm for PIN genotype, and screen and determine the genotype mother plants with an oil content of ≥50% as seed source donors. Specifically, superior trees were selected: 30 mother trees with a fruit yield of more than 2,000 seeds per tree were selected from the dwarf pine forest at an altitude of 1,100 m in the Huzhong Nature Reserve of the Greater Khingan Mountains (52°18' N latitude), and DNA was extracted from their needles. Genotyping: PCR amplification was performed using the primers in Table 1 to screen out mother trees with PinFAD2 alleles of F / F and PinDGAT of D3 / D3 (kernel oil content 53.2%–58.7%). Based on the key genes for oil synthesis in Pinus sylvestris (PinFAD2, PinDGAT), SSR markers were designed (see Table 1) to screen superior tree germplasm with high oil content (≥50%) and high cold resistance (SOD enzyme activity ≥350U / g FW) from wild populations; Seed treatment: Soak the superior tree seeds in a 0.2% GA3 + 0.1% salicylic acid compound solution (4℃) for 48 hours, then air dry for later use.

[0014] The salicylic acid-gibberellin compound solution activated the endogenous hormone pathway in seeds, reducing ABA content by 62% and increasing the GA / ABA ratio to 3.2 times that of wild species.

[0015] Table 1: Primer sequences of SSR markers related to pine resin S2, temperature-light synergistic germination regulation: Seeds from the seed donor were soaked in a compound solution of 0.2% gibberellin and 0.1% salicylic acid and treated at 4℃±0.5℃ for 48 hours; then the seeds were transferred to a programmable light and temperature chamber to execute a three-temperature gradient germination regulation program: Phase I (0-15 days): Day / night temperature is 18℃ / 5℃, red light with wavelength of 660nm is used for irradiation for 12 hours / day, and light intensity is 80μmol·m⁻²·s⁻¹; Phase II (16-30 days): Day / night temperature is 10℃ / -2℃, blue light with wavelength of 450nm is used for irradiation for 8 hours / day, and UV-B irradiation of 2.8W / m² is supplemented for 1 hour / day. Phase III (31-45 days): Implement a temperature gradient change from -5℃ to 8℃ at a rate of 0.5℃ / h and at a uniform rate, using full-spectrum irradiation for 6 hours / day; Specifically, the primary prerequisite for seed germination is to break dormancy and activate basal metabolism. This stage is achieved by soaking the seeds in a compound solution of 0.2% gibberellin and 0.1% salicylic acid, combined with low-temperature treatment at 4℃±0.5℃ for 48 hours. This constructs a dual awakening system of hormone signal activation and low-temperature vernalization, laying the foundation for subsequent germination.

[0016] The three-stage gradient regulation of the programmable light and temperature chamber follows the physiological progression of germination initiation, cold resistance induction, and temperature difference acclimatization.

[0017] In stage I, a daytime temperature of 18°C ​​provides the optimal environment for enzyme activity in the division and elongation of radicle cells. At this time, the energy released by respiration can be used efficiently for cell growth. A nighttime temperature of 5°C reduces the rate of respiration, minimizes the ineffective consumption of nutrients, and ensures the directional transport of energy-storing substances such as soluble sugars to the tip of the radicle.

[0018] 660nm is the optimal absorption wavelength for seed phytochromes. Red light irradiation can rapidly convert phytochromes from inactive to active forms.

[0019] In Phase II, a nighttime temperature of -2℃ is considered a moderately low temperature, which can activate cold-resistance signaling pathways in seeds and induce the expression of cold-response genes. A daytime temperature of 10℃ provides the basic conditions for cell repair and substance synthesis. This temperature difference setting avoids cell freezing damage caused by continuous low temperatures and effectively stimulates stress-resistant metabolism.

[0020] 450nm blue light accelerates the conversion of phenylalanine to anthocyanins by activating cryptochrome receptors in seeds. Anthocyanins, as powerful antioxidants, can scavenge reactive oxygen species generated at low temperatures, while also enhancing cell membrane stability and forming a direct protective barrier against cold.

[0021] In stage III, the extreme low temperature of -5℃ strongly induces the expression of the proline synthase gene. Proline, as a key osmotic regulator, can lower the freezing point by increasing the cell sap concentration, while protecting the spatial structure of proteins and enzymes and preventing cell dehydration damage caused by low temperature. As the temperature gradually rises to 8℃, seed respiration and substance synthesis gradually recover, stabilizing the storage of stress-resistant substances such as proline.

[0022] Simulating natural light conditions across the entire spectrum, it can simultaneously activate phytochromes (red light response), cryptochromes (blue light response), and ultraviolet photoreceptors (UV response), achieving synergistic regulation of multiple light signaling pathways. The 6-hour irradiation duration ensures the basic expression of photosynthesis-related genes, reserving photosynthetic capacity for subsequent seed germination, while avoiding energy consumption caused by excessively long light exposure.

[0023] S3, Frozen Soil Defense Structure Planting: Select a sunny slope with a gradient of ≤10°, and dig planting holes with dimensions of 60cm×60cm×50cm. The planting holes adopt a three-layer composite frozen soil defense structure, with each layer from bottom to top as follows: Bottom layer: A 15cm thick layer of basalt gravel is laid, with a particle size of 3-5cm and mixed with 5% biochar by mass. Middle layer: Lay a 30cm thick mixed substrate, which is a mixture of humus, peat, and vermiculite in a volume ratio of 5:3:2, with a pH value of 5.0–6.0; Surface layer: A 10cm thick moss layer is laid, in which 15% by mass of phase change microcapsules are mixed. The phase change microcapsules are a composite of paraffin and expanded graphite, with a phase change point of -8℃ and a latent heat of phase change ≥210J / g. S4, IoT dynamic management: Each group consists of 5 seedlings, and each group is equipped with one multi-parameter sensor node. The sensor node includes a root temperature probe and an FDR moisture content sensor, with the root temperature probe buried at a depth of 25cm and the FDR moisture content sensor buried at a depth of 15cm. Establish a LoRa self-organizing network with a transmission distance of ≥3km to monitor root zone temperature and soil conductivity data in real time. When the root zone temperature T so ᵢ l When the temperature is below -5℃, the carbon crystal heating plate of the corresponding planting hole will be automatically activated, with a power of 120W / hole. When the soil electrical conductivity EC is greater than 1.5mS / cm, the drip irrigation system will be automatically triggered to leach salt, with a leaching flow rate of 8L / min.

[0024] It should be noted that the dual-mode power supply design is as follows: the photovoltaic panels (conversion efficiency 23%) supply power to the carbon crystal heating plate, with an average daily power generation of 1.2 kWh / m². Thermoelectric generators (ZT value ≥ 1.2) generate electricity using the temperature difference between geothermal energy and air to supplement nighttime energy. Intelligent control algorithm: Based on LSTM model to predict the depth of frozen soil, the heating advance is up to 30 minutes, and the overall energy saving is 51%.

[0025] In one embodiment of this application, the phase change microcapsules in step S3 are core-shell composite structures, prepared by combining a paraffin core and an expanded graphite shell; the latent heat of phase change of the paraffin core is ≥180J / g, the porosity of the expanded graphite shell is 92%, and the amount of phase change microcapsules incorporated into the surface moss is 15% of the dry weight of the moss.

[0026] Specifically, the core-shell composite structure substrate is prepared by melting paraffin (melting point -8℃) and injecting it into expanded graphite (particle size 2–4 mm), then cooling and crushing it into 1–3 mm particles. Thermal barrier effect: When the rhizosphere temperature drops to -8℃, the phase variant melts and absorbs heat, stabilizing the root layer temperature above -3℃ (14.2℃ higher than the traditional method).

[0027] In one embodiment of this application, the programmable light and temperature box in step S2 has a built-in height-adjustable LED light source frame. The height of the LED light source frame is adaptively adjustable within a range of 20–50 cm. The height adaptive adjustment ensures that the spatial variation coefficient of light intensity in the seedling area is <5%.

[0028] A seedling cultivation device for Pinus tabuliformis based on the coordinated regulation of temperature gradient and photoperiod includes a temperature and photoperiod coordinated regulation unit, a permafrost defense structure unit, and an Internet of Things management unit. The temperature and light synergistic regulation unit includes a closed seedling chamber 1, such as Figure 3 As shown, the seedling chamber is divided into three independent temperature control zones by partition 2. An LED light source matrix 3 is installed in the seedling chamber. The temperature control range of the independent temperature control zones is -10℃–25℃, with a control accuracy of ±0.3℃. The LED light source matrix 3 supports three-channel switching of red light 660nm, blue light 450nm and full spectrum. It should be noted that the seedling chamber 1 is made of polyurethane thermal insulation board, which has both thermal insulation and pressure resistance properties, and can effectively isolate external temperature fluctuations. The partition 2 has thermal insulation properties, and the three independent temperature control zones correspond to the three key stages of low-temperature germination of dwarf pine seeds, seedling cultivation and hardening, which can simulate the temperature gradient environment of the native high-altitude area of ​​dwarf pine.

[0029] The 660nm red light, 450nm blue light, and full-spectrum mode are adapted to the photosynthetic needs of dwarf pine at different growth stages; at the same time, the LED light source matrix has a programmable 3-photoperiod setting, which can accurately match the dwarf pine's light-loving and side-shading growth habits.

[0030] The permafrost defense structural unit includes a honeycomb ceramic matrix with a pore size of 5mm, filled with phase change microcapsules, and covered with a breathable non-woven fabric with a basis weight of 80g / m². It should be noted that the porous structure of the honeycomb ceramic matrix ensures root aeration, enhances structural stability, and improves heat conduction efficiency. The matrix is ​​filled with phase change microcapsules, which can absorb and release heat through solid-liquid phase change, effectively inhibiting soil freezing in the root zone and preventing frost damage to the roots of dwarf pine seedlings.

[0031] Non-woven fabric combines breathability, water retention, and soil erosion prevention, which can maintain stable moisture in the seedling substrate while preventing leakage of phase change microcapsules and blockage of honeycomb ceramic channels by substrate particles.

[0032] The IoT management unit includes a dual-band soil radar and an edge computing gateway. The dual-band soil radar operates at a frequency of 1GHz / 250MHz and is used to scan the depth of the frozen soil layer in the seedling area in real time. The edge computing gateway pre-stores heating control strategies. The power calculation formula for the control strategy is: P=K1·e^(0.2ΔT), where ΔT is the difference between the set temperature and the measured temperature in the root zone, the coefficient K1=50W / ℃, and P is the heating power.

[0033] It should be noted that the IoT management unit enables real-time monitoring and intelligent control of the seedling environment, and the dual-band soil radar can scan the thickness of the frozen soil layer in the seedling area in real time. The data is transmitted wirelessly to the edge computing gateway.

[0034] The edge computing gateway pre-stores heating control strategies for dwarf pine seedling cultivation. It can dynamically adjust the heating power according to the depth of the frozen soil layer and the temperature difference, so as to achieve rapid heating and precise constant temperature control, avoiding damage to seedlings caused by temperature overshoot.

[0035] The present application and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present application. The actual structure is not limited to this. In conclusion, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of the present application, such design should fall within the protection scope of the present application.

Claims

1. A method for cultivating *Pinus sylvestris* seedlings based on the synergistic regulation of temperature gradient and photoperiod, characterized in that, Includes the following steps: S1, marker-assisted screening of seed source: In the natural distribution area of ​​Pinus sylvestris, collect superior tree germplasm with an age of ≥30 years, an interannual coefficient of variation of fruit yield <15%, and good health free from pests and diseases; use SSR molecular marker technology to screen the superior tree germplasm for PIN genotype, and screen and determine the genotype mother plants with an oil content of ≥50% as seed source donors. S2, Temperature-Photosynergistic Germination Regulation: Seeds from the aforementioned seed donor were soaked in a compound solution of 0.2% gibberellin and 0.1% salicylic acid and treated at 4℃±0.5℃ for 48 hours; subsequently, the seeds were transferred to a programmable light-temperature chamber and subjected to a three-temperature gradient germination regulation program. Phase I (0-15 days): Day / night temperature is 18℃ / 5℃, red light with wavelength of 660nm is used for irradiation for 12 hours / day, and light intensity is 80μmol·m⁻²·s⁻¹; Phase II (16-30 days): Day / night temperature is 10℃ / -2℃, blue light with wavelength of 450nm is used for irradiation for 8 hours / day, and UV-B irradiation of 2.8W / m² is supplemented for 1 hour / day. Phase III (31-45 days): Implement a temperature gradient change from -5℃ to 8℃ at a rate of 0.5℃ / h and at a uniform rate, using full-spectrum irradiation for 6 hours / day; S3, Frozen Soil Defense Structure Planting: Select a sunny slope with a gradient of ≤10°, and dig planting holes with dimensions of 60cm×60cm×50cm. The planting holes adopt a three-layer composite frozen soil defense structure, with each layer from bottom to top as follows: Bottom layer: A 15cm thick layer of basalt gravel is laid, the basalt gravel having a particle size of 3-5cm and being mixed with 5% biochar by mass. Middle layer: A 30cm thick mixed substrate is laid, which is composed of humus, peat and vermiculite in a volume ratio of 5:3:2, with a pH value of 5.0–6.0; Surface layer: A 10cm thick moss layer is laid, in which 15% by mass of phase change microcapsules are mixed. The phase change microcapsules are a composite of paraffin and expanded graphite, with a phase change point of -8℃ and a latent heat of phase change ≥210J / g. S4, IoT dynamic management: Each group consists of 5 seedlings, and each group is equipped with one multi-parameter sensor node; the sensor node includes a root temperature probe and an FDR moisture content sensor, wherein the root temperature probe is buried at a depth of 25cm and the FDR moisture content sensor is buried at a depth of 15cm. Establish a LoRa self-organizing network with a transmission distance of ≥3km to monitor root zone temperature and soil conductivity data in real time. When the root zone temperature T so ᵢ l When the temperature is below -5℃, the carbon crystal heating plate of the corresponding planting hole will be automatically activated. The power of the carbon crystal heating plate is 120W / hole. When the soil electrical conductivity EC is greater than 1.5mS / cm, the drip irrigation system will be automatically triggered to perform salt leaching. The leaching flow rate of the drip irrigation system is 8L / min.

2. The method according to claim 1, characterized in that, The phase change microcapsules in step S3 have a core-shell composite structure, which is prepared by combining a paraffin core and an expanded graphite shell; the latent heat of phase change of the paraffin core is ≥180J / g, the porosity of the expanded graphite shell is 92%, and the amount of phase change microcapsules incorporated into the surface moss is 15% of the dry weight of the moss.

3. The method according to claim 1, characterized in that, The programmable light and temperature box in step S2 has a built-in height-adjustable LED light source frame. The height of the LED light source frame is adaptively adjustable within a range of 20–50 cm. Through height adaptive adjustment, the spatial variation coefficient of light intensity in the seedling area is ensured to be <5%.

4. A seedling cultivation device for *Pinus sylvestris* based on the coordinated regulation of temperature gradient and photoperiod, characterized in that, It includes a temperature and light coordinated regulation unit, a permafrost defense structure unit, and an Internet of Things management unit; The temperature and light synergistic control unit includes a sealed seedling chamber (1), which is divided into three independent temperature control zones by a partition (2). An LED light source matrix (3) is installed in the seedling chamber (1). The temperature control range of the independent temperature control zones is -10℃–25℃, and the control accuracy is ±0.3℃. The LED light source matrix (3) supports three-channel switching of red light 660nm, blue light 450nm and full spectrum. The permafrost defense structural unit includes a honeycomb ceramic matrix with a pore size of 5 mm and filled with phase change microcapsules. The surface of the honeycomb ceramic matrix is ​​covered with a breathable non-woven fabric with a basis weight of 80 g / m². The IoT management unit includes a dual-band soil radar and an edge computing gateway. The dual-band soil radar operates at a frequency of 1GHz / 250MHz and is used to scan the depth of the frozen soil layer in the seedling area in real time. The edge computing gateway pre-stores a heating control strategy. The power calculation formula for the control strategy is: P=K1·e^(0.2ΔT), where ΔT is the difference between the set temperature and the measured temperature in the root zone, the coefficient K1=50W / ℃, and P is the heating power.

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