A method for mass production of gynostemma pentaphyllum seedlings

Abstract

This invention relates to the field of plant cultivation technology and discloses a method for mass production of Drynaria fortunei seedlings. By constructing a complete and standardized operating procedure from spore pretreatment to seedling transplantation, and with the assistance of zoned environmental control facilities, the method achieves precise and stable management of key parameters at each growth stage, ultimately realizing efficient, high-quality, and large-scale production of Drynaria fortunei seedlings.

Description

Technical Field

[0001] This invention relates to the field of plant cultivation technology, and more specifically, to a method for mass production of Drynaria fortunei seedlings. Background Technology

[0002] As an important medicinal fern, *Drynaria fortunei* enjoys strong market demand, but wild resources are nearing depletion due to over-harvesting. The development of its artificial cultivation industry is constrained by a stable and efficient supply of seedlings. Spore reproduction is the main sexual reproduction method for large-scale fern seedling production, but existing *Drynaria fortunei* spore reproduction technology faces significant bottlenecks, resulting in low production efficiency and high costs, making it difficult to meet industrialization needs.

[0003] Traditional spore propagation methods in greenhouses or simple facilities typically involve: collecting spores in the wild, simply disinfecting them, and then sowing them in soil or humus substrate; maintaining humidity naturally or through simple means; and allowing them to germinate and grow naturally. The main drawback of this existing technology is that: (1) The spore treatment is crude and the germination foundation is poor: There is a lack of effective spore selection and activation steps, empty spores and impurities, resulting in a low germination rate (usually <30%) and asynchronous germination.

[0004] (2) The growth environment control depends on experience and has poor stability: it depends on natural climate or simple greenhouses. The light, temperature and humidity fluctuate drastically and cannot meet the refined environmental requirements of each stage of spore germination, prothallium and sporophyte. The growth is slow and the deformity rate is high.

[0005] (3) The management process is loose and cannot form a standard process: From sowing, moisturizing, and staged cultivation to seedling hardening, each step is mostly operated by manual experience. There is a lack of unified and repeatable technical standards and operating procedures, resulting in huge differences in seedling quality between different batches, making it impossible to achieve stable mass production.

[0006] (4) The transplanting process causes significant damage and results in a low survival rate: Traditional bare-root transplanting methods severely damage the fragile root system of fern seedlings, resulting in a long recovery period after transplanting and an unstable survival rate, which affects the uniformity of subsequent cultivation.

[0007] Therefore, it is necessary to propose a new method for mass propagation of Drynaria fortunei seedlings. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a systematic, streamlined, and mass-production method for *Drynaria fortunei* seedlings. This invention establishes a complete and standardized operational process from spore pretreatment to seedling transplantation, coupled with zoned environmental control facilities, to achieve precise and stable management of key parameters at each growth stage, ultimately realizing efficient, high-quality, and large-scale production of *Drynaria fortunei* seedlings.

[0009] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A method for mass production of Drynaria fortunei seedlings, comprising the following steps: S1. Spore collection and refined pretreatment: Collection: Collect coarse spore powder; Impurity removal: Density gradient centrifugation is used for purification and impurity removal. The density difference between spores and impurities is used to separate and collect highly viable, plump spore bands. Activation: The spores after impurity removal are treated with ultrasound to break down the spore wall barrier through cavitation, thereby achieving physical activation; S2. Preparation of spore suspension and germination substrate: Preparation of spore suspension: Wash the activated spores with sterile water by centrifugation, resuspend them in germination medium, and adjust the spore concentration to 10. 3 -10 5 spores / mL; Preparation of three-layer germination substrate: A disposable transparent lunchbox is used as the seedling tray. The germination substrate is layered into the tray. The three layers of germination substrate, from bottom to top, include a bottom layer, a middle layer, and a top layer. The bottom layer, as a drainage and aeration layer, is made up of a layer of 100-200 mesh crushed sand. The middle layer, as a vegetative growth layer, is made up of a mixture of peat moss, vermiculite, rice husk charcoal, and decomposed mushroom residue. The top layer, as a sowing support layer, is made up of vermiculite that has passed through a 200 mesh sieve and activated carbon powder with a particle size of 1-3 mm. The seedling tray is sterilized in a 121℃ high-pressure steam oven for 30 minutes and then cooled for later use. Sowing: Use a spray bottle to evenly spray the spore suspension onto the surface of the germination substrate to complete the sowing; S3. Phased facility-based cultivation management: After sowing, the seedling boxes are sequentially moved into the three pre-set functional cultivation areas for management; Phase 1: Germination zone management, from sowing to the prothallus stage, with daytime temperature of 22-25℃, nighttime temperature of 18-20℃, humidity of 70-90%, light duration of 10-12 h / d, and light intensity of 1000-1500 lx; The second stage: management of the growth area, from the prothallus to the sporophyte stage, with daytime temperature of 22-28℃, nighttime temperature of 20-25℃, humidity of 70-90%, light duration of 10-12 h / d, and light intensity of 1500-2000 lx. Phase 3: Hardening-off management. The hardening-off area is equipped with large seedbeds 1.8 m wide and 21 m long. The seedbeds are covered with a 5 cm thick layer of peat moss, which is then thoroughly watered. Seedlings are transplanted into the seedbeds in clumps of 2-3, using a grid to control the spacing between clumps at 5 cm × 5 cm. Light intensity is gradually increased to over 2000 lx, while humidity is gradually reduced to 60%. Temperature is controlled at 20–28℃ by increasing ventilation, creating natural diurnal fluctuations. The seedlings are hardened off by gradually reducing the frequency of misting, increasing ventilation time, and increasing light intensity. S4. Seedling transplanting: After hardening off, the water-based gel root-protecting transplanting method is adopted: the seedlings are gently removed from the substrate, and their roots are completely immersed in the biopolysaccharide solution so that the roots are coated with the biopolysaccharide solution. Then, they are removed and planted in a planting site containing calcium ions. When the polysaccharide solution on the surface of the roots comes into contact with calcium ions, it quickly forms a soft hydrated gel protective layer, which effectively protects the roots during the transplanting process and reduces water loss and mechanical damage.

[0010] In one embodiment, during the impurity removal in step S1, the coarse spores are centrifuged in a Percoll cell separation solution with a mass concentration of 10-50% or a sucrose gradient solution with a mass concentration of 10-50% to separate and collect highly viable, plump spore bands by utilizing the density difference between spores and impurities.

[0011] In one embodiment, during the activation in step S1, the frequency of the ultrasonic treatment is 40–60 kHz, the power of the ultrasonic treatment is 80–100 W, and the ultrasonic treatment time is 30–60 seconds.

[0012] In one embodiment, in the spore suspension preparation in step S2, the germination solution is a 0.1M MS salt solution, and 4.0 mg / L of gibberellin hormone such as gibberellin (GA3) is added as a germination inducer, and the pH is adjusted to 5.8.

[0013] In one embodiment, in the preparation of the three-layer germination substrate in step S2, in the middle layer, peat soil, vermiculite, rice husk charcoal, and decomposed mushroom residue are mixed in a volume ratio of 2:1:1:1; in the surface layer, vermiculite and activated carbon powder are mixed in a volume ratio of 9:1.

[0014] In one embodiment, in the preparation of the three-layer germination substrate in step S2, the thickness of the bottom layer is 0.2-0.5 cm, the thickness of the middle layer is 2-3 cm, and the thickness of the top layer is 0.1-0.3 cm.

[0015] In one embodiment, in step S3, the first stage management time is 15 to 30 days, the second stage management time is 40 to 90 days, and the third stage management time is 30 to 60 days.

[0016] In one embodiment, in step S3, the hardening-off area of ​​stage three is equipped with a large seedbed that is 1.8 m wide and 21 m long. The seedbed is covered with peat moss that is about 5 cm thick. After the peat moss is laid, it is thoroughly watered. The seedlings are transplanted to the seedbed in clumps of 2-3 seedlings each, and the clump spacing is controlled to be 5 cm × 5 cm using a grid board.

[0017] In one embodiment, in step S4, the biopolysaccharide solution is a sodium alginate solution with a mass concentration of 1-2%.

[0018] In summary, the present invention has the following beneficial effects: This invention fundamentally improves germination quality and efficiency: through a combination of "gradient centrifugation for impurity removal" and "ultrasonic physical activation" pretreatment, ineffective spores are efficiently removed, significantly improving the vitality and germination synchronicity of the spore population, increasing the germination rate from less than 30% to over 80%, thus laying the foundation for mass production of seed sources.

[0019] This invention achieves stable and controllable precision cultivation: through "zoning facility design" and "clear parameter setting", the complex growth process is decomposed into three stages, and basic environmental control equipment (LED lights, humidifiers, fans, etc.) is used to achieve stable and precise management of key environmental factors in each stage, overcoming the fundamental problem of large environmental fluctuations in traditional methods, shortening the growth cycle by about 30%, and producing uniform seedlings.

[0020] This invention establishes a replicable, standardized production system: the entire technical solution, from spore treatment and substrate formulation to environmental parameters and agronomic operations at each stage, has been developed into clear and quantifiable standard operating procedures (SOPs). This makes the production process no longer dependent on personal experience, and it is easy to fully replicate in different production bases, truly realizing the transformation from experience-based to standardized and large-scale production.

[0021] This invention significantly improves transplant survival rate and subsequent growth potential: the "water-based gel root protection transplanting method" provides physical protection and moisture buffer for seedling roots at key transplanting stages, minimizing transplant damage, stabilizing the survival rate at over 95%, and shortening the seedling recovery period, thus ensuring efficient cultivation in the future.

[0022] This invention has significant advantages for industrialization: the method of this invention does not rely on an expensive intelligent central control system, but is mainly based on process design, zoning facilities and standardized operations. It has low investment and operating costs, is simple to operate, and is very suitable for promotion and application in a wide range of production areas. It can effectively and economically solve the seedling bottleneck problem in the industrialization of Drynaria fortunei. Attached Figure Description

[0023] Figure 1This is a schematic diagram of Drynaria fortunei spores being cultured in a stage-one environment after sowing; Figure 2 This is a schematic diagram of the germination of *Drynaria fortunei* spores into prothallus after sowing; Figure 3 This is a schematic diagram of the Drynaria prothallus developing into a young sporophyte; Figure 4 This is a diagram showing the state of *Drynaria fortunei* sporophytes before transplanting to the seedbed at stage three; Figure 5 This is a schematic diagram of Drynaria fortunei spores being cultured in a stage two environment after sowing; Figure 6 It involves instructing workers to transfer the *Drynaria fortunei* seedlings to the stage three seedbed; Figure 7 This is a schematic diagram of Drynaria fortunei seedlings being cultured in a stage-three environment; Figure 8 Workers transplanted the seedlings to the planting area under the forest. Detailed Implementation

[0024] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] It is worth noting that the directional terms such as "up" and "down" used in this article are all relative to the perspective of the attached figures and are only for the purpose of description. They should not be interpreted as limitations on the technical solutions.

[0026] like Figure 1-8 As shown, this invention proposes a method for mass production of Drynaria fortunei seedlings, which has the advantages of being systematic and streamlined. The steps of this invention are as follows: S1. Spore collection and refined pretreatment: Collection: Collect coarse spore powder; Impurity removal: Density gradient centrifugation is used for purification and impurity removal. The density difference between spores and impurities is used to separate and collect highly viable, plump spore bands. Activation: The spores after impurity removal are treated with ultrasound to break down the spore wall barrier through cavitation, thereby achieving physical activation; S2. Preparation of spore suspension and germination substrate: Preparation of spore suspension: Wash the activated spores with sterile water by centrifugation, resuspend them in germination medium, and adjust the spore concentration to 10. 3 -10 5 spores / mL; Preparation of three-layer germination substrate: A disposable transparent lunch box is used as a seedling box. The germination substrate is layered into the box. The three layers of germination substrate include a bottom layer, a middle layer and a top layer from bottom to top. The bottom layer is a drainage and aeration layer, which is made up of a layer of 100-200 mesh crushed sand. The middle layer is a vegetative growth layer, which is made up of a mixture of peat moss, vermiculite, rice husk charcoal and decomposed mushroom residue. The top layer is a sowing and bearing layer, which is made up of vermiculite that has passed through a 200 mesh sieve and activated carbon powder with a particle size of 1-3 mm. Sowing: Use a spray bottle to evenly spray the spore suspension onto the surface of the germination substrate to complete the sowing; S3. Phased facility-based cultivation management: After sowing, the seedling boxes are sequentially moved into the three pre-set functional cultivation areas for management; Phase 1: Germination zone management, from sowing to the prothallus stage, with daytime temperature of 22-25℃, nighttime temperature of 18-20℃, humidity of 70-90%, light duration of 10-12 h / d, and light intensity of 1000-1500 lx; The second stage: management of the growth area, from the prothallus to the sporophyte stage, with daytime temperature of 22-28℃, nighttime temperature of 20-25℃, humidity of 70-90%, light duration of 10-12 h / d, and light intensity of 1500-2000 lx. The third stage: seedling hardening management, gradually increasing the light intensity to over 2000 lx and gradually reducing the humidity to 60%, controlling the temperature at 20-28℃ by strengthening ventilation to create natural diurnal fluctuations, and gradually reducing the frequency of spraying, increasing the ventilation time and light intensity to harden the seedlings against stress. S4. Seedling transplanting: After the seedlings have hardened off, the water-based gel root-protection transplanting method is used: the seedlings are gently removed from the substrate, and their roots are briefly and completely immersed in the biopolysaccharide solution. Then they are removed and planted in a planting site containing calcium ions. The polysaccharide solution on the surface of the roots quickly forms a soft hydrated gel protective layer when it comes into contact with calcium ions, thereby effectively protecting the roots during the transplanting process and reducing water loss and mechanical damage.

[0027] This invention establishes a complete and standardized operating procedure from spore pretreatment to seedling transplantation, and combines it with zoned environmental control facilities to achieve precise and stable management of key parameters at each growth stage, ultimately realizing efficient, high-quality, and large-scale production of Drynaria fortunei seedlings.

[0028] Preferably, in the impurity removal step S1, the coarse spores are centrifuged in a Percoll cell separation solution with a mass concentration of 10-50% or a sucrose gradient solution with a mass concentration of 10-50% to separate and collect highly viable, plump spore bands by utilizing the density difference between spores and impurities.

[0029] Preferably, in the activation step S1, the frequency of the ultrasonic treatment is 40-60 kHz, the power of the ultrasonic treatment is 80-100 W, and the ultrasonic treatment time is 30-60 seconds.

[0030] Preferably, in the preparation of the spore suspension in step S2, the germination solution is a 0.1M MS salt solution, and 4.0 mg / L of gibberellin hormone such as gibberellin (GA3) is added as a germination inducer, and the pH is adjusted to 5.8.

[0031] Preferably, in the preparation of the three-layer germination substrate in step S2, in the middle layer, peat soil, vermiculite, rice husk charcoal, and decomposed mushroom residue are mixed in a volume ratio of 2:1:1:1; in the surface layer, vermiculite and activated carbon powder are mixed in a volume ratio of 9:1.

[0032] Preferably, in the preparation of the three-layer germination substrate in step S2, the thickness of the bottom layer is 0.2-0.5 cm, the thickness of the middle layer is 2-3 cm, and the thickness of the top layer is 0.1-0.3 cm.

[0033] Preferably, in step S3, the first stage management time is 15 to 30 days, the second stage management time is 40 to 90 days, and the third stage management time is 30 to 60 days.

[0034] Preferably, in step S3, the hardening-off area is equipped with a large seedbed that is 1.8 m wide and 21 m long. The seedbed is covered with a layer of peat moss about 5 cm thick. After the peat moss is laid, it is thoroughly watered. The seedlings are transplanted into the seedbed in clumps of 2-3 seedlings each, and the clump spacing is controlled to be 5 cm × 5 cm using a grid board.

[0035] Preferably, in step S4, the biopolysaccharide solution is a sodium alginate solution with a mass concentration of 1-2%.

[0036] The technical solution of the present invention will be described below with reference to specific embodiments.

[0037] This invention involves sequentially performing gradient flotation to remove impurities and ultrasonic physical activation after spore collection; preparing a standardized spore suspension containing a germination inducer; preparing a three-layer germination substrate with drainage, nutrition, and seed-bearing functions; and conducting progressive cultivation management in a zoned cultivation facility (germination zone, growth zone, and hardening zone) based on clearly defined environmental parameters (light, temperature, humidity, ventilation, and nutrition) for each stage; and transplanting seedlings using a water-based gel root-preserving transplanting method after seedling formation.

[0038] The specific steps are as follows: S1. Spore collection and refined pretreatment: Collection: During the mature stage of the sporangia (i.e. when the spores are brownish-brown), collect the sporangia in a clean environment, dry them, shake them off, and collect the coarse spore powder.

[0039] Impurity removal: Purification and impurity removal are carried out by density gradient centrifugation. The coarse spores are placed in a Percoll cell separation solution or sucrose gradient solution of a specific concentration (10%-50%) and centrifuged. The high viability of the plump spore bands is separated and collected by utilizing the density difference between the spores and impurities.

[0040] Activation: Selected spores are placed in a low-frequency ultrasonic cleaning device and treated for 30-60 seconds under specific parameters (40-60 kHz, 100W). The cavitation effect gently breaks down the spore wall barrier, enhancing its water absorption and metabolic activity, thus achieving physical activation.

[0041] S2. Preparation of spore suspension and germination substrate: Spore suspension preparation: Activated spores were washed by centrifugation with sterile water and resuspended in a dedicated germination medium. This germination medium was a diluted MS salt solution with the addition of a low concentration of gibberellin (GA3, 4.0 mg / L) as a germination inducer. The pH was adjusted to 5.8, and the spore concentration was adjusted to 10. 5 spores / mL.

[0042] Preparation of the three-layer germination substrate: Bottom layer (drainage and aeration layer): 0.2-0.5 cm thick, made of a layer of 200-mesh crushed sand; Middle layer (vegetative growth layer): 2-3 cm thick, made of peat moss, vermiculite, rice husk charcoal, and decomposed mushroom residue in a predetermined volume ratio (2:1:1:1); Top layer (sowing support layer): 0.1-0.3 cm thick, made of finely sieved vermiculite and activated carbon powder (9:1), which plays a role in uniformly supporting spores, moisturizing, and inhibiting algae; Fill the above three-layer structure into a uniformly sized transparent lidded disposable lunch box (i.e., seedling box).

[0043] Sowing: Use a spray bottle to evenly spray the spore suspension onto the surface of the germination substrate to complete the sowing; S3. Phased facility-based cultivation management: After sowing, the seedling boxes are sequentially moved into the three pre-set functional cultivation areas for management; Phase 1: Germination Zone Management (from sowing to prothallus stage, approximately days 1-30). Facilities and Environment: Daytime temperature 22-25℃, nighttime temperature 18-20℃, humidity 70-90%, light duration 10-12 h / d, light intensity 1000-1500 lx, keep the lid tightly closed to maintain substrate moisture. After sowing, transfer all disposable containers to this area. Control light intensity and photoperiod using a timer.

[0044] Phase Two: Growth Zone Management (Prothallus to Sporophyte Stage, approximately days 31-75). Facilities and Environment: Daytime temperature 22–28℃, nighttime temperature 20–25℃, humidity 70–90%, light duration 10–12 h / d, light intensity 1500–2000 lx, keep the substrate moist by tightly covering the container. After prothallus formation, transfer the specimens to this zone. Control light intensity and photoperiod using a timer.

[0045] Phase 3: Hardening-off Area Management (approximately day 76-100). Facilities and Environment: The hardening-off area is equipped with large seedbeds, 1.8 m wide and 21 m long, covered with approximately 5 cm of peat moss. High-powered exhaust fans and retractable shade nets are also provided. After the seedbeds are prepared, water them thoroughly. Transplant seedlings in clumps of 2-3 to the seedbeds, using a grid to control the clump spacing at 5 cm × 5 cm. Environmental parameters are gradually adjusted: light intensity is gradually increased to over 2000 lx, humidity is gradually reduced to around 60%, and ventilation is increased to create natural diurnal temperature fluctuations (20-28℃). The seedlings are hardened off by gradually reducing the frequency of misting, increasing ventilation time, and increasing light intensity.

[0046] S4. Seedling transplanting: After hardening off, the water-based gel root-protection transplanting method is used: The seedlings are gently removed from the substrate, and their roots are briefly immersed in a bio-polysaccharide solution (1-2% sodium alginate solution). They are then removed and transplanted into a planting area containing calcium ions (such as pre-treated calcium chloride solution or calcium-rich soil). The polysaccharide solution on the root surface quickly forms a soft, hydrated gel protective layer upon contact with calcium ions, effectively protecting the roots during transplanting and reducing water loss and mechanical damage. Optionally, the planting site can be prepared in advance, and a weed control tarpaulin with planting holes can be laid to prevent weeds from affecting the growth of the *Drynaria fortunei* seedlings in the early stages of transplanting (e.g., ...). Figure 8 (As shown).

[0047] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for mass production of *Drynaria fortunei* seedlings, characterized in that, The steps are as follows: S1. Spore collection and refined pretreatment: Collection: Collect coarse spore powder; Impurity removal: Density gradient centrifugation is used for fine impurity removal, taking advantage of the density difference between spores and impurities to separate and collect highly viable, plump spore bands; Activation: The spores after impurity removal are treated with ultrasound to break down the spore wall barrier through cavitation, thereby achieving physical activation; S2. Preparation of spore suspension and germination substrate: Spore suspension preparation: The activated spores were washed by centrifugation with sterile water and resuspended in germination solution to a spore concentration of 10 3 -10 5 spores / mL. Preparation of three-layer germination substrate: A disposable transparent lunchbox was used as the seedling tray. The germination substrate was layered into the tray, consisting of a bottom layer, a middle layer, and a top layer from bottom to top. The bottom layer, serving as a drainage and aeration layer, consisted of a layer of 100-200 mesh crushed sand. The middle layer, serving as a vegetative growth layer, was composed of a mixture of peat moss, vermiculite, rice husk charcoal, and decomposed mushroom residue, with an equal mass of sterile water-moistened substrate added. The top layer, serving as a sowing support layer, consisted of a mixture of activated carbon powder that had passed through a 200 mesh sieve and vermiculite with a particle size of 1-3 mm. The seedling tray was then sterilized in a 121℃ high-pressure steam oven for 30 minutes and allowed to cool before use. Sowing: Use a spray bottle to evenly spray the spore suspension onto the surface of the germination substrate to complete the sowing; S3. Phased facility-based cultivation management: After sowing, the seedling boxes are sequentially moved into the three pre-set functional cultivation areas for management; Phase 1: Germination zone management, from sowing to the prothallus stage, with daytime temperature of 22-25℃, nighttime temperature of 18-20℃, humidity of 70-90%, light duration of 10-12 h / d, and light intensity of 1000-1500 lx; The second stage: management of the growth area, from the prothallus to the sporophyte stage, with daytime temperature of 22-28℃, nighttime temperature of 20-25℃, humidity of 70-90%, light duration of 10-12 h / d, and light intensity of 1500-2000 lx. The third stage: seedling hardening management, gradually increasing the light intensity to over 2000 lx and gradually reducing the humidity to 60%, controlling the temperature at 20-28℃ by strengthening ventilation to create natural diurnal fluctuations, and gradually reducing the frequency of spraying, increasing the ventilation time and light intensity to harden the seedlings against stress. S4. Seedling transplanting: After the seedlings have hardened off, the water-based gel root-protection transplanting method is used: the seedlings are gently removed from the substrate, their roots are completely immersed in the biopolysaccharide solution, and then they are removed and planted in a planting site containing calcium ions. The polysaccharide solution on the surface of the roots quickly forms a soft hydrated gel protective layer when it comes into contact with calcium ions, thereby effectively protecting the roots during the transplanting process and reducing water loss and mechanical damage.

2. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In step S1, the crude spores are centrifuged in Percoll cell separation medium with a mass concentration of 10-50% or sucrose gradient medium with a mass concentration of 10-50%. The high-viability, plump spore bands are separated and collected by utilizing the density difference between spores and impurities.

3. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In the activation step S1, the frequency of the ultrasonic treatment is 40-60 kHz, the power of the ultrasonic treatment is 80-100 W, and the ultrasonic treatment time is 30-60 seconds.

4. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In step S2, the spore suspension preparation is a 0.1M MS salt solution with 4.0 mg / L gibberellin added as a germination inducer, and the pH is adjusted to 5.

8.

5. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In the preparation of the three-layer germination substrate in step S2, in the middle layer, peat soil, vermiculite, rice husk charcoal, and decomposed mushroom residue are mixed in a volume ratio of 2:1:1:1; in the surface layer, vermiculite and activated carbon powder are mixed in a volume ratio of 9:

1.

6. The method for mass production of *Drynaria fortunei* seedlings as described in claim 5, characterized in that, In the preparation of the three-layer germination substrate in step S2, the thickness of the bottom layer is 0.2-0.5 cm, the thickness of the middle layer is 2-3 cm, and the thickness of the top layer is 0.1-0.3 cm.

7. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In step S3, the first stage of management lasts for 15 to 30 days, the second stage lasts for 40 to 90 days, and the third stage lasts for 30 to 60 days.

8. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In step S3, the third stage of hardening off the seedlings is equipped with seedbeds. The seedbeds are covered with a 5 cm thick layer of peat moss. After the peat moss is laid, it is thoroughly watered. The seedlings are transplanted into the seedbed in clumps of 2-3 seedlings, and the clump spacing is controlled to be 5 cm × 5 cm using a grid board.

9. The method for mass production of *Drynaria fortunei* seedlings as described in claim 1, characterized in that, In step S4, the biopolysaccharide solution is a sodium alginate solution with a mass concentration of 1-2%.

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