Method for promoting malania oleifera seed germination and seedling growth

Abstract

The invention relates to a method for promoting malania oleifera seed germination and seedling growth. The method comprises the following steps of harvesting, airing, peeling and cleaning, grinding and thinning, seed soaking and disinfection, treatment of river sand for three-section variable-temperature sand storage, three-section variable-temperature sand storage, seedbed preparation, sowing and transplanting. Through a mild physical method of grinding and thinning the shells, the permeability obstacle of the seed shells is effectively overcome; furthermore, through a three-stage variable-temperature sand storage procedure in the variable-temperature sand storage step, the temperature change of the original habitat of the malania oleifera is simulated, and the after-ripening and germination processes of the embryos are precisely regulated and controlled, so that deep dormancy is cooperatively broken. According to the technical system for promoting malania oleifera seed germination and seedling growing rate established by the method, dormancy is broken (the dormancy period of several months in a traditional method is shortened to about 90 days, and germination can be started 16 days after sand storage), the germination seedling growing rate is increased by 98.33%, the transplanting survival rate is increased by 98.26%, and a solid seedling growing technical support is provided for malania oleifera population recovery and seedling artificial forest culture.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of forest seedling breeding, and particularly relates to a method for promoting seed germination and seedling growth of Malania oleifera. BACKGROUND

[0002] Malania oleifera Malania oleifera Malania oleifera Chun et S. Lee is a dicotyledonous evergreen arbor tree species of the genus Malania of the Ximeniaceae of the Olacaceae of the Santalales, is a rare and endangered plant with a single genus in China, is naturally distributed in a narrow karst rocky desertification region in the southeast of Yunnan and the west of Guangxi, is a national second-class protected plant, is listed in the Red List of Endangered Species of the World Natural Protection Union as a vulnerable grade, and based on the endangered grade and standard 3.1 version of the IUCN Red List of Species, the vulnerable standard of Malania oleifera is A2c.

[0003] Malania oleifera is poor in soil, is an excellent ecological tree species for preventing and treating rocky desertification, has a fine wood structure, straight grain and luster, and is an ideal furniture material. More importantly, Malania oleifera kernels are rich in a monounsaturated long-chain fatty acid, i.e., nervonic acid (NA, cis-15-tetracosenoic acid), and the content of nervonic acid in seed oil is as high as 55.7%-67.0%, which is the highest content of nervonic acid in plants known so far. Nervonic acid is a unique material that can promote the repair and regeneration of damaged nerve tissues, and has important effects on improving brain nerve activity and treating nervous system diseases such as senile dementia, cerebral palsy, brain atrophy, memory loss and insomnia and forgetfulness, and can be used as a medicine and a health product.

[0004] Malania oleifera has extremely high medicinal, economic, ecological and scientific research values, and development of a Malania oleifera industry is of great significance to population sustainability recovery protection, rocky desertification treatment and integrated development and utilization. However, the seeds of Malania oleifera have typical deep dormancy characteristics, i.e., hard and dense seed coat, poor permeability, and morphological and physiological dormancy of seed embryos, and are difficult to germinate under natural conditions, with a germination and seedling growth rate of less than 20%, low propagation efficiency, especially low seedling emergence rate and uneven germination, and a cycle of more than one year. Conventional sand storage is prone to rotting, root rot, uneven germination and cannot be used for large-scale and efficient production of seedlings, which seriously restricts the protection and development and utilization of the species.

[0005] Currently, several technologies have attempted to solve the propagation problems of garlic cloves. For example, patent CN107466782A involves germinating seeds in a sand bed after cleaning the mucus from the seed surface, but this method fails to effectively overcome seed coat barriers and deep dormancy, resulting in low and uneven germination rates. Patent CN117063661A uses grinding the seed coat and soaking the seeds in gibberellin, but its germination process is conducted under constant temperature conditions, failing to simulate natural temperature changes to effectively break physiological dormancy, and its core invention lies in the germination equipment. Patent CN117598150B uses amino acid to corrode the seed coat, which has some effect, but the strong acid treatment carries the risk of damaging the embryo, resulting in poor operational safety and controllability.

[0006] Therefore, existing technologies have failed to provide a safe, efficient, controllable, and scalable method for breaking dormancy and cultivating seedlings from garlic pods. Developing a comprehensive technology that can synergistically address both physical barriers in the seed coat and physiological dormancy in the embryo is a critical issue that urgently needs to be solved in this field. Summary of the Invention

[0007] Technical problem to be solved: In view of the shortcomings of the existing technology, the present invention provides a method for promoting the germination and seedling formation of garlic clove seeds. This method can quickly and efficiently break the deep dormancy of garlic clove seeds, significantly improve the germination and seedling formation rate, and is applicable to large-scale production of seed germination and seedling formation methods.

[0008] Technical solution: A method for promoting the germination of garlic clove seeds and the emergence of seedlings, comprising the following steps: (1) Harvesting: Harvest mature, round, firm and uniformly sized fruits from natural garlic fruit populations from early to mid-October. (2) Drying, peeling and cleaning: spread the fruit flat on the drying bed in the shade shed and dry in the shade for 5-7 days. After the peel has lost water and softened, remove the peel by hand or machine. Clean with a 5% sodium chloride solution to remove impurities, as well as unripe and insect-infested fruits. Rinse the selected fruits twice with clean water. (3) Grinding and thinning: Mix the fruit after cleaning in step (2) with sand with a particle size of 0.5 mm at a volume ratio of 1:6, grind for 45-50 minutes, and grind the fruit shell to a thickness of 0.4-0.5 mm; (4) Seed soaking and disinfection: Wash the fruit with clean water after grinding and thinning the shell, dry it, disinfect it with disinfectant, and then soak the seeds in gibberellin solution; (5) Treatment of river sand for variable temperature sand storage: The river sand is screened with a sieve with a 2mm aperture and disinfected with potassium permanganate. After disinfection, it is rinsed with running water and drained for 2 hours. Then, water is sprayed according to the moisture content of the river sand to make the moisture content of the river sand uniform and the moisture content is 55%. (6) Variable temperature sand storage: Mix the fruit soaked in step (4) with the river sand treated in step (5) at a volume ratio of 1:5, pack them into 80-100 mesh nylon mesh bags, 20 kg per bag, and carry out three-stage variable temperature sand storage treatment. (7) Seedbed preparation: In a flat and well-drained nursery, seedbeds are spaced 50cm apart both longitudinally and laterally. Seedbeds are 1.2m wide and 5cm high with a flat surface. Then, a 15cm thick layer of sterilized river sand is evenly covered on the surface of the seedbed. (8) Sowing: After the fruit seeds were stored in the sand at varying temperatures in step (6), place them neatly on the seedbed in step (7) with the seed holes facing down and at a spacing of 6×6cm. Cover the top with 5cm of sterilized river sand, cover with a film to keep warm, sterilize every 15 days, and keep the sand bed humidity at 55%. (9) Transplanting: After the seedlings from step (8) have grown to 10-12cm in height, transplant the seedlings into nutrient pots filled with nutrient soil, water them thoroughly, spray them once with a 700-800 times diluted solution of 50% carbendazim wettable powder, place the nutrient pots on the raised beds in the greenhouse, insert a bamboo strip every 1.5m on the raised beds, bend it into an arched frame, cover it with plastic film and press it tightly with soil to form a small arched greenhouse, maintain the relative humidity in the small greenhouse at 75-80% and the temperature at 25-27℃.

[0009] The natural garlic fruit population in step (1) above has a tree age of 15-20 years, a tree height of 15-20m, and a trunk diameter at breast height of 25-30cm; the fruit has a longitudinal diameter of 3.8-4.0cm, a transverse diameter of 4.0-4.5cm, and a weight of 40-45g.

[0010] The drying bed in step (2) above is 3m long, 1.2m wide, and 0.8m above the ground. The drying net of the drying bed is a galvanized woven wire mesh with a mesh size of 10mm × 10mm.

[0011] In step (3) described above, the grinding process is performed using a drum grinder.

[0012] The disinfection method in step (4) above is to soak the seeds in a 0.5% potassium permanganate solution for 2 hours or in a 5% sodium hypochlorite solution for 90 minutes; the method of soaking the seeds in gibberellin solution is to soak them in a 200 mg / L gibberellin solution for 24 hours at a soaking temperature of 25°C.

[0013] The method of potassium permanganate disinfection in step (5) above is to soak in a 0.5% potassium permanganate solution for 1 hour, with the volume ratio of river sand to potassium permanganate solution being 1:2.

[0014] The three-stage variable-temperature sand storage treatment in step (6) described above is as follows: the first stage is the initial low-temperature treatment, which lasts from day 1 to 30, and the temperature is kept constant at 4-5℃; the second stage is the mid-term high-temperature treatment, which lasts from day 31 to 75, with the temperature set at 25℃ from 5:00 to 21:00 every day and at 10℃ from 21:00 to 5:00 the next morning; the third stage is the final medium-temperature treatment, which lasts from day 76 to 90, and the temperature is kept constant at 22℃.

[0015] The preparation methods for disinfected river sand in steps (7) and (8) above are as follows: disinfect with a 0.5% potassium permanganate solution, using 600 mL of 0.5% potassium permanganate solution per kg of river sand, stir evenly and let stand for 30 minutes, then add water to adjust the moisture content to 55%; or use an 800-fold dilution of 50% carbendazim wettable powder, using 3000 mL of 800-fold dilution of 50% carbendazim wettable powder per kg of river sand, stir evenly, cover with plastic film and let stand for 4 hours, remove the film and air dry for 2 days, then add water to adjust the moisture content to 55%.

[0016] In step (8) described above, sterilization is performed every 15 days using a 50% carbendazim wettable powder solution diluted 800 times per cubic meter. 3 Use 3L of diluted solution for the seedbed, spraying until the topsoil is thoroughly moistened without water accumulation.

[0017] The preparation method of the nutrient soil in step (9) above is as follows: First, mix peat soil, fully decomposed sweet tea shells, perlite, and decomposed organic fertilizer in a weight ratio of 10:5:3:2 to obtain a mixture. Then, add 2 kg of powdered calcium magnesium phosphate fertilizer, 0.3 kg of ferrous sulfate, 50 g of 50% carbendazim wettable powder, and 40 g of 70% mancozeb wettable powder per m³ of mixture. While stirring, spray water to make the moisture content reach 55%. After stirring evenly, cover with a film and let it ferment. The mixture can be piled for 7 days to obtain the final product; alternatively, first mix humus, fully decomposed sweet tea husks, perlite, and decomposed organic fertilizer in a weight ratio of 10:5:3:2 to obtain a mixed material. Then, add 2 kg of powdered calcium magnesium phosphate fertilizer, 0.3 kg of ferrous sulfate, 0.1 kg of borax, 50 g of 50% carbendazim wettable powder, and 40 g of 70% mancozeb wettable powder per m³ of the mixed material. While stirring, spray water to make the moisture content reach 55%. After stirring evenly, cover with a film and pile for 7 days to obtain the final product.

[0018] Beneficial effects: The method for promoting the germination of garlic clove seeds and seedling growth provided by this invention has the following beneficial effects: 1. High efficiency in breaking dormancy: By using a gentle physical method of grinding to thin the seed coat, the permeability barrier of the seed coat is effectively overcome. Furthermore, a carefully designed three-stage variable-temperature sand stratification program simulates the temperature changes in its native environment, precisely controlling the after-ripening and germination processes of the embryo, thereby synergistically breaking deep dormancy. This method is safe, controllable, and highly reproducible. It shortens the dormancy period of traditional methods (several months) to approximately 75-90 days, allowing seedlings to emerge as early as 20-25 days after sowing.

[0019] 2. Significantly improved germination rate and uniformity: The seed germination rate is stable at over 93%, with concentrated germination, germination vigor of over 90%, and high uniformity.

[0020] 3. High seedling quality: The seedlings are robust, with a transplant survival rate of over 97%, laying a high-quality seedling foundation for subsequent afforestation and industrialization.

[0021] 4. The technology can be applied on a large scale: The method has a clear process, well-defined parameters, and is easy to standardize, making it suitable for large-scale seedling production of garlic cloves.

[0022] 5. This invention establishes a stable and efficient technical system for promoting the germination and seedling rate of garlic clove seeds by optimizing fruit selection standards, sun-drying, peeling and cleaning, thinning of the fruit shell, disinfection and soaking, variable-temperature sand stratification, seedbed sowing, and transplanting in nutrient pots. It breaks dormancy, increases the germination and seedling rate to over 93%, and the transplant survival rate to over 97%, providing key technical support for the recovery of garlic clove populations and artificial afforestation. Attached Figure Description

[0023] Figure 1 This is a morphological diagram of garlic cloves during the harvesting process in Example 1, in which... Figure 1 A represents the mature fruit of the garlic clove tree; Figure 1 B represents the harvested garlic cloves; Figure 1 C represents the garlic fruit after the outer pericarp has been removed.

[0024] Figure 2 This is a diagram showing the morphology of garlic cloves during the drying and peeling process in Example 1. Figure 2 A. Soak the garlic cloves in a 5% sodium chloride solution and rinse them with clean water. Figure 2 B represents the garlic fruit after its shell has been thinned.

[0025] Figure 3 This is a morphological diagram of the garlic clove fruit that has broken open and begun to sprout after being subjected to variable-temperature sand stratification treatment in Example 1.

[0026] Figure 4 The image shows the morphology of the seeds and seedlings that germinated in the seedbed in Example 1.

[0027] Figure 5The images show the morphological characteristics of the transplanted seedlings and seedlings in Example 1. Figure 5 A represents seedlings transplanted into nutrient pots; Figure 5 B and Figure 5 C represents seedlings that have successfully survived transplanting. Detailed Implementation

[0028] The present invention will be further described in detail below through specific embodiments. However, those skilled in the art will understand that the following embodiments are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention.

[0029] This invention establishes a high-efficiency seedling propagation technology system for garlic clove seeds by controlling key aspects such as fruit treatment, seed pretreatment, sand stratification conditions, and seedling environment. The following four examples and four comparative examples, combined with detailed data, verify the technical effectiveness. All experiments were conducted at the garlic clove native habitat seedling base in Leye County, Baise City, Guangxi (between 106°10′~106°51′E, 24°30′~25°03′N, altitude 900-1000m), with an experimental period of 12 months (October 2023-October 2024). Each treatment was replicated three times, and the data were averaged. Example 1

[0030] Example 1 is the basic optimization group (focusing on variable-temperature sand storage and fruit shell treatment), and the specific steps are as follows: (1) Fruit harvesting: On October 7, 2023, 600 plump fruits with a longitudinal diameter of 3.8-4.0 cm, a transverse diameter of 4.0-4.4 cm, and a single fruit weight of 40-45 g were collected from healthy 20-year-old mother trees with a height of 15-20 m and a diameter at breast height of 25-30 cm. Deformed and insect-damaged fruits (such as...) were removed. Figure 1 A, Figure 1 As shown in B).

[0031] (2) Sun-drying, peeling, and cleaning: The fruit is laid flat on a 0.8m high shaded drying bed (the drying bed is 3m long, 1.2m wide, and 0.8m above the ground; the drying net is a galvanized woven wire mesh with a mesh size of 10mm × 10mm), and air-dried for 6 days. The softened peel is then removed manually (e.g., Figure 1 After soaking in a 5% sodium chloride aqueous solution for 35 minutes (as shown in C), remove floating fruits, rinse twice with clean water, and obtain 420 clean fruits (as shown in C). Figure 2 (As shown in A).

[0032] (3) Grinding to thin the shell: The fruit and sand with a particle size of 0.5 mm were mixed at a volume ratio of 1:6 and ground using a drum grinder for 50 minutes. The shell thickness was measured to be reduced to 0.4-0.5 mm (e.g., Figure 2As shown in B), the wax layer removal rate reached over 85%.

[0033] (4) Seed disinfection: Soak the fruits with thinned shells in a 0.5% potassium permanganate solution for 2 hours, rinse with clean water, and then soak in a 200 mg / L gibberellin solution (25℃ constant temperature) for 24 hours.

[0034] (5) Treatment of river sand for variable temperature sand storage: The river sand is passed through a 2mm sieve and soaked in a 0.5% potassium permanganate solution for 1 hour. The volume ratio of river sand to potassium permanganate solution is 1:2. Rinse with running water until neutral, drain for 2 hours, and adjust to a moisture content of 55% (by mass, it can be formed into a ball when squeezed by hand and easily dispersed when touched).

[0035] (6) Variable temperature sand storage: Mix the fruits soaked in step (4) with the river sand treated in step (5) at a volume ratio of 1:5, and pack them into 80-mesh breathable nylon bags (20kg per bag). The sand storage procedure is divided into three stages: the first stage is the initial low temperature treatment, that is, the temperature is kept constant at 4-5°C from day 1 to 30; the second stage is the mid-term high temperature treatment, that is, the temperature is set at 28°C during the day (5:00-21:00, a total of 16 hours) and 10°C at night (21:00-5:00 the next day, a total of 8 hours) from day 31 to 75; the third stage is the final medium temperature treatment, that is, the temperature is set at 22°C constant from day 76 to 90. During the sand storage period, the seeds are turned over and water is added every 7 days to keep the humidity fluctuation less than ±2%. After 16 days of sand storage, the seed coat begins to crack. After 90 days of sand storage, a total of 413 seeds have cracked seed coats and radicles have sprouted (e.g. Figure 3 As shown in the figure, the seed germination rate reached 98.33% (413 seeds / 420 seeds).

[0036] (7) Seedbed preparation: The seedbed size is 1.2m × 12m × 5cm. The seedbeds are spaced 50cm apart both longitudinally and laterally. Cover with 15cm thick sterilized river sand (using a 50% carbendazim wettable powder diluted 800 times, using 3000mL of 50% carbendazim wettable powder diluted 800 times per kg of river sand, stirring evenly, covering with plastic film and letting it sit for 4 hours, uncovering the film and turning it over to dry for 2 days, then watering to adjust the moisture content to about 55%). Adjust the moisture content to 55%.

[0037] (8) Sowing: 413 seeds with cracked seed coats and sprouting radicles are sown at 6cm×6cm intervals (seed holes facing down), covered with 5cm of sterilized river sand (using an 800-fold dilution of 50% carbendazim wettable powder, using 3000mL of 800-fold carbendazim wettable powder per kg of river sand, stirred evenly, covered with plastic film and left to stand for 4 hours, then uncovered and air-dried for 2 days, then watered to adjust the moisture content to about 55%). Temperature control is maintained by covering with film (25-26℃ during the day, 18-19℃ at night). Every 15 days, apply an 800-fold dilution of 50% carbendazim wettable powder (per m³). 3 The dosage is 3 L). 22 days after sowing, some seeds began to germinate from the cotyledons. 30 days after sowing, the seeds began to germinate rapidly, with a final yield of 408 germinated seeds (e.g., ...). Figure 4 As shown), the germination rate was 98.79% (408 seeds / 413 seeds), and the germination potential was 95.65% (number of germinations during peak germination period / total number of germinations).

[0038] (9) Transplanting: Seedlings 10-12cm tall (e.g.) Figure 5 When transplanting (as shown in A), the seedlings should be placed in a container filled with nutrient soil (nutrient soil preparation: mix peat moss, fully decomposed sweet tea husks, perlite, and decomposed organic fertilizer in a weight ratio of 10:5:3:2 to obtain a uniform mixture; then add 2 kg of powdered calcium magnesium phosphate fertilizer, 0.3 kg of ferrous sulfate, 50 g of 50% carbendazim wettable powder, and 40 g of 70% mancozeb wettable powder per m³ of mixture, while stirring and spraying water to adjust the moisture content). After reaching 55%, mix evenly, cover with film and let it ferment for 7 days. Put the nutrient pots (15cm×20cm) in a nutrient pot, water it thoroughly, and spray it once with a 700-800 times diluted solution of 50% carbendazim wettable powder. Place the nutrient pots on the raised beds in the greenhouse. Insert one bamboo strip every 1.5m on the raised beds, bend it into an arched frame, cover it with plastic film and press it tightly with soil to seal it, forming a small arched greenhouse. Maintain the relative humidity in the small greenhouse at 80% and the temperature at 25-26℃.

[0039] A total of 408 seedlings were transplanted. Two months after transplanting, 401 seedlings had survived. Figure 5 B, Figure 5 As shown in C), the transplanting survival rate reached 98.28% (401 seedlings / 408 seedlings). The average height of the seedlings was 35.26 cm, and the average length of the taproot was 21.58 cm. Example 2

[0040] Example 2 is the nutrient soil optimization group (focusing on substrate formula improvement), and the specific steps are as follows: Steps (1), (2), (3), (4), (5), (6), (7), and (8) are the same as in Example 1. 420 seeds were stored in sand at varying temperatures. After 21 days of storage, the seed coats of some seeds began to crack and the radicles began to sprout. After 90 days of storage, a total of 414 seeds had cracked seed coats and sprouted radicles, with a seed germination rate of 98.57% (414 seeds / 420 seeds).

[0041] Twenty days after sowing, some seeds began to germinate from the soil, and by thirty days, they began to germinate in large numbers. In the end, 407 seeds germinated and emerged, with a germination rate of 98.31% (407 seeds / 414 seeds) and a germination vigor of 95.34%.

[0042] Step (9) The specific steps for transplanting are as follows: When the seedlings are 10-12cm tall, transplant them into a container filled with nutrient soil (nutrient soil preparation: mix humus, fully decomposed sweet tea husks, perlite, and decomposed organic fertilizer in a weight ratio of 10:5:3:2 to obtain a mixture. Then add 2kg of powdered calcium magnesium phosphate fertilizer, 0.3kg of ferrous sulfate, 0.1kg of borax, 50g of 50% carbendazim wettable powder, and 40g of 70% mancozeb wettable powder per m³ of mixture, while stirring and spraying water to make it contain nutrient soil). When the water content reaches 55%, stir evenly, cover with film and let it ferment for 7 days. Put the nutrient pots (15cm×20cm) in a pot, water them thoroughly, spray them once with a 700-800 times diluted solution of 50% carbendazim wettable powder, place the nutrient pots on the raised beds in the greenhouse, insert a bamboo strip every 1.5m on the raised beds, bend it into an arched frame, cover it with plastic film and press it tightly with soil to seal it, forming a small arched greenhouse. Maintain the relative humidity of the small greenhouse at 80% and the temperature at 24-25℃.

[0043] A total of 407 seedlings were transplanted. Two months after transplanting, 402 seedlings survived, resulting in a survival rate of 98.77% (402 seedlings / 407 seedlings). The average height of the seedlings was 38.51 cm, and the average length of the taproot was 22.85 cm. Example 3

[0044] Example 3 is the seed soaking reagent optimization group (focusing on hormone synergistic treatment). This example aims to explore the effect of gibberellin concentration and naphthaleneacetic acid synergistic effect on breaking dormancy. The steps are the same as in Example 1, except that in step (4) seed soaking disinfection, the concentration of gibberellin solution is adjusted to 250 mg / L, and 50 mg / L naphthaleneacetic acid is added at the same time (the temperature of the mixed solution is kept at 25°C), and the other parameters remain unchanged.

[0045] 420 seeds were stored in sand at varying temperatures. After 20 days of storage, the seed coats of some seeds began to crack and the radicles began to sprout. After 90 days of storage, the seed coats of 415 seeds had cracked and the radicles had begun to sprout, with a germination rate of 98.81% (415 seeds / 420 seeds).

[0046] At 18 days after sowing, some seeds began to germinate from the cotyledons, and by 28 days, germination was concentrated. Ultimately, 407 seeds germinated and emerged, resulting in a germination rate of 98.07% (407 seeds / 415 seeds) and a germination potential of 96.82%. This indicates that appropriately increasing the gibberellin concentration can further promote germination under the variable temperature system of this invention.

[0047] A total of 407 seedlings were transplanted. Two months after transplanting, 401 seedlings survived, resulting in a survival rate of 98.53% (401 seedlings / 407 seedlings). The average height of the seedlings was 34.41 cm, and the average length of the taproot was 20.19 cm. Example 4

[0048] Example 4 is the sand storage cycle optimization group (75 days) (focusing on low temperature and temperature difference control). This example aims to verify the possibility of shortening the variable temperature sand storage cycle. The steps are basically the same as in Example 1, but the variable temperature sand storage program is adjusted: the first stage (1-25 days, 4°C), the second stage (26-65 days, 28°C / 10°C variable temperature), and the third stage (66-75 days, 22°C / 10°C variable temperature), with a total duration of 75 days.

[0049] Of the 420 seeds stored in sand at varying temperatures, 13.9% showed seed coat cracking and radicle sprouting after 17 days. After 65 days, 95.8% of the seeds showed seed coat cracking and radicle sprouting. After 75 days, 409 seeds showed seed coat cracking and radicle sprouting, achieving a germination rate of 97.38% (409 seeds / 420 seeds). This result indicates that, while ensuring effective dormancy breaking in most seeds, the storage time can be appropriately shortened to 75 days, providing flexibility for production applications.

[0050] 409 seeds with cracked seed coats and sprouting radicles were sown. 25 days after sowing, the cotyledons of some seeds began to emerge and germinate. By 35 days, the sown seeds germinated in a concentrated manner, and finally 402 seeds germinated and emerged as seedlings, with a germination rate of 98.28% (402 seeds / 409 seeds) and a germination vigor of 94.71%.

[0051] A total of 402 seedlings were transplanted. Two months after transplanting, 395 seedlings survived, resulting in a survival rate of 98.26% (395 seedlings / 402 seedlings). The average height of the seedlings was 33.75 cm, and the average length of the taproot was 21.38 cm.

[0052] Comparative Example 1 was the group without grinding treatment. The step of grinding with a drum grinder for 50 minutes was omitted to demonstrate the necessity of grinding to thin the shell. The steps were basically the same as in Example 1, but step (3) of grinding with a drum grinder for 50 minutes was omitted. 420 seeds were sterilized and soaked before being stored in sand at variable temperature.

[0053] When the seeds were stored in sand at varying temperatures for 55 days, no visible changes were observed in the seed coat. When the seeds were stored in sand at varying temperatures for 90 days, only 40.69% of the seeds showed cracked seed coats and the radicles slightly protruded (171 seeds).

[0054] 171 seeds with radicle germination were sown. 60 days after sowing, a small number of seeds germinated from the cotyledons, and ultimately 124 seeds germinated into seedlings, with a germination rate of only 72.51%. Moreover, the germination period lasted for as long as 3 months and was extremely uneven. This indicates that without grinding the garlic cloves using a drum grinder, even with variable-temperature sand stratification, it is difficult to effectively overcome the seed coat barrier.

[0055] Comparative Example 2 was a constant-temperature sand storage group, used to demonstrate the superiority of variable-temperature sand storage over constant-temperature sand storage. The steps were basically the same as in Example 1, except that the variable-temperature sand storage in step (6) was replaced with constant-temperature sand storage at 15°C for 90 days. 420 seeds were subjected to variable-temperature sand storage after disinfection and soaking.

[0056] During constant temperature sand storage, the seed coat of the fruit did not crack and the radicle did not sprout until day 47. By day 90 of constant temperature sand storage, only 37.14% of the fruit seed coats had cracked (156 seeds).

[0057] 156 seeds with radicle germination were sown. 45 days after sowing, some seeds with cracked seed coats began to germinate, and ultimately 103 seeds germinated into seedlings, with a germination rate of 66.03%. This germination rate and germination potential were significantly lower than those of the variable-temperature sand stratification treatment described in this invention, demonstrating that variable-temperature stimulation is crucial for breaking the physiological dormancy of garlic pods.

[0058] Comparative Example 3 was the gibberellin-free treatment group, used to verify the synergistic promoting effect of gibberellin. The steps were basically the same as in Example 1, except that in step (4) seed soaking and disinfection, only disinfection was performed, and gibberellin was not used for seed soaking. 420 seeds were subjected to variable-temperature sand stratification after disinfection and soaking.

[0059] The seeds were not stratified in sand at varying temperatures until day 52 when the seed coats cracked and the radicles began to sprout. After 90 days of stratification in sand at varying temperatures, only 79.52% of the seeds (334 seeds) showed seed coat cracking and radicle sprouting.

[0060] 334 seeds with radicle germination were sown. 45 days after sowing, some seeds with cracked seed coats began to germinate, with 269 seeds ultimately germinating into seedlings, resulting in a germination rate of 80.53%. This germination rate and germination vigor were significantly lower than those treated with gibberellin in this invention, demonstrating that gibberellin treatment plays a crucial role in breaking the physiological dormancy of garlic pods and promoting seed germination and seedling formation.

[0061] Comparative Example 4 served as a control group for existing technologies, following the method described in Example 1 of patent CN117598150B. Seeds were soaked in a 10% sulfamic acid aqueous solution at room temperature for 4 hours, rinsed, and then soaked in a mixture of 150 mg / L gibberellin and 100 mg / L chitosan for 1 hour. Following this, seeds were stratified in sand at a constant temperature (23°C) for 40 days to promote germination. After 40 days of constant temperature sand stratification, no obvious seed coat cracking or germination was observed. Germination began after 120 days of continued cultivation, with a final germination rate of 85.0%. While this method achieved a satisfactory final germination rate, it did not significantly shorten the germination period, and the strong acid treatment increased the risk of embryo damage. Furthermore, the operational complexity and cost were higher than those of this invention.

[0062] The following is a data analysis of Examples 1-4 and Comparative Examples 1-4, the contents of which are as follows.

[0063] 1. Comparison data of the effects of the four sets of examples (as shown in Table 1 below) The average germination and seedling survival rate was 96.20% ± 2.45%; the average transplant survival rate was 97.96% ± 0.41%; the average time to initial germination was 20.0 ± 3.4 days; and the germination potential was 90.7%-92.7%.

[0064] Table 1 Example Radicle initial germination time (d) Complete cracking, radicle germination rate (%) Germination potential (%) Germination and seedling rate (%) Transplanting survival rate (%) Average plant height (cm) Average taproot length (cm) Technical features Example 1 16 98.33 95.65 98.79 98.28 35.26 21.58 Optimized group, overall effect is optimal Example 2 20 98.57 95.34 98.31 98.77 38.51 22.85 Nutrient soil optimization group, seedling quality is best Example 3 18 98.81 96.82 98.07 98.53 34.41 20.19 Hormone synergy group, high germination uniformity Example 4 17 97.38 94.71 98.28 98.26 33.75 21.38 Cycle optimization group, can be shortened to 75 d 2.4 Comparison of Technical Methods and Analysis of Major Defects (as shown in Table 2 below) Table 2 Comparative example Treatment method Radicle initial germination time (d) Complete cracking, radicle germination rate (%) Germination and seedling rate (%) Main defects Comparative example 1 No grinding treatment 55 40.69 72.51 Seed shell permeability barrier cannot be overcome Comparative example 2 Constant temperature 15℃ sand storage 47 37.14 66.03 Cannot break physiological dormancy Comparative example 3 No gibberellin treatment 52 79.52 80.53 Lack of hormone regulation Comparative example 4 CN117598150B method 120 85.0 85.0 Strong acid treatment, moldy rate 8.9%, germination cycle is long (120 d) The following is a quantitative analysis of the technical effects of Examples 1-4 and Comparative Examples 1-4, the contents of which are as follows.

[0065] 1. Analysis of Germination Efficiency Advantages The invention utilizes an innovative three-stage variable-temperature sand storage technology: low-temperature dormancy breaking (4-5℃ low-temperature treatment for 30 days effectively breaks deep dormancy of the embryo); temperature difference promoting development (25℃ / 10℃ diurnal temperature difference stimulates rapid embryo development); and gentle physical treatment (grinding and thinning the shell to 0.4-0.5mm to improve permeability without damaging the embryo), resulting in a significant improvement in germination efficiency.

[0066] In Example 1, the time for the seed coat to begin cracking and the radicle to sprout was only 16 days, which was about 60% shorter than the average in the literature, and 70.09% and 66.96% shorter than Comparative Experiment 1 (without grinding) and Comparative Experiment 2 (without temperature variation), respectively. The germination and seedling rate was 98.79%, which was 12.65% higher than the average in the literature and 36.24% higher than Comparative Experiment 1. The core reason is the synergistic effect of low temperature breaking dormancy, diurnal temperature difference promoting seed embryo development, and shell grinding improving water absorption efficiency.

[0067] Table 3 shows a comparative analysis of the three-stage variable-temperature sand stratification technology and existing technologies in terms of seed germination time and germination and seedling rate.

[0068] Table 3 Index Optimal value of the present application Literature average Improvement range Initial germination time 16 d 40 d Shortened by 60.0% Germination and seedling rate 98.79% 87.70% Increased by 12.7% 2. Advantages Analysis of Comparative Experiments By comparing the system with four comparative examples, the significant advantages of the present invention were verified. The technical advantages are analyzed in Table 4 below.

[0069] Table 4

[0070] 3. Technical Stability Analysis The germination and seedling survival rate of the four examples had a coefficient of variation of only 1.5% and a transplant survival rate of only 0.9%, which is far lower than the coefficient of variation of transplant survival rate of 12.3%-18.5% in the comparative experiment. This shows that the technical system of the present invention has strong reproducibility and is suitable for large-scale seedling cultivation.

[0071] 4. Analysis of the advantages in seedling quality Through innovative nutrient soil formulation, a mixture of 50% humus, 25% decomposed sweet tea husks, 15% perlite, and 10% organic fertilizer was added, along with 2 kg / m³ of calcium magnesium phosphate, 0.3 kg / m³ of ferrous sulfate, and 0.1 kg / m³ of borax, meeting the specific nutrient requirements of garlic seedlings. Examples 1, 2, 3, and 4 all showed transplant survival rates exceeding 98%, 35.3%-35.7% higher than the literature average and 36.1%-38.9% higher than ordinary garden soil. The key lies in the ample organic matter (humus + decomposed sweet tea husks) and trace elements (borax, ferrous sulfate) provided by the improved nutrient soil, meeting the root development needs of the seedlings. The advantages in seedling quality are analyzed in Table 5 below.

[0072] Table 5 Quality index Example 2 data Improvement range Technical reasons Plant height 38.51 cm 12.3% Optimized nutrient soil formula provides sufficient nutrients Taproot length 22.86 cm 15.2% Borax and other trace elements promote root development Transplanting survival rate 98.77% Increased by 2.6% compared with literature Robust root system improves stress resistance 5. Endangered Conservation Value As a national second-class protected plant, the natural germination and seedling rate of garlic fruit is less than 20% (Illustrated Handbook of Rare and Endangered Plants of China, 2023). This invention increases the seed coat cracking and radicle germination rate to over 97% and the seedling rate to over 98.26%, providing key technical support for its population expansion. It is still a significant breakthrough compared to the best technology recorded in existing literature (germination and seedling rate of 80% and seedling rate of 85%).

[0073] The embodiments of the present invention have been described in detail above. For those skilled in the art, there may be changes in the specific implementation methods and application scope based on the ideas of the embodiments of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for promoting the germination of garlic bulb seeds and seedling emergence, characterized in that... Includes the following steps: (1) Harvesting: Harvest mature, round, firm and uniformly sized fruits from natural garlic fruit populations from early to mid-October. (2) Drying, peeling and cleaning: spread the fruit flat on the drying bed in the shade shed and dry in the shade for 5-7 days. After the peel has lost water and softened, remove the peel by hand or machine. Clean with a 5% sodium chloride solution to remove impurities, as well as unripe and insect-infested fruits. Rinse the selected fruits twice with clean water. (3) Grinding and thinning: Mix the fruit after cleaning in step (2) with sand with a particle size of 0.5 mm at a volume ratio of 1:6, grind for 45-50 minutes, and grind the fruit shell to a thickness of 0.4-0.5 mm; (4) Seed soaking and disinfection: Wash the fruit with clean water after grinding and thinning the shell, dry it, disinfect it with disinfectant, and then soak the seeds in gibberellin solution; (5) Treatment of river sand for variable temperature sand storage: The river sand is screened with a sieve with a 2mm aperture and disinfected with potassium permanganate. After disinfection, it is rinsed with running water and drained for 2 hours. Then, water is sprayed according to the moisture content of the river sand to make the moisture content of the river sand uniform and the moisture content is 55%. (6) Variable temperature sand storage: Mix the fruit soaked in step (4) with the river sand treated in step (5) at a volume ratio of 1:5, pack them into 80-100 mesh nylon mesh bags, 20 kg per bag, and carry out three-stage variable temperature sand storage treatment. (7) Seedbed preparation: In a flat and well-drained nursery, seedbeds are spaced 50cm apart both longitudinally and laterally. Seedbeds are 1.2m wide and 5cm high with a flat surface. Then, a 15cm thick layer of sterilized river sand is evenly covered on the surface of the seedbed. (8) Sowing: After the fruit seeds were stored in the sand at varying temperatures in step (6), place them neatly on the seedbed in step (7) with the seed holes facing down and at a spacing of 6×6cm. Cover the top with 5cm of sterilized river sand, cover with a film to keep warm, sterilize every 15 days, and keep the sand bed humidity at 55%. (9) Transplanting: After the seedlings from step (8) have grown to 10-12cm in height, transplant the seedlings into nutrient pots filled with nutrient soil, water them thoroughly, spray them once with a 700-800 times diluted solution of 50% carbendazim wettable powder, place the nutrient pots on the raised beds in the greenhouse, insert a bamboo strip every 1.5m on the raised beds, bend it into an arched frame, cover it with plastic film and press it tightly with soil to form a small arched greenhouse, maintain the relative humidity in the small greenhouse at 75-80% and the temperature at 25-27℃.

2. The method for promoting seed germination and seedling growth of garlic cloves according to claim 1, characterized in that: The natural garlic fruit population in step (1) has a tree age of 15-20 years, a tree height of 15-20m, and a trunk diameter at breast height of 25-30cm; the fruit has a longitudinal diameter of 3.8-4.0cm, a transverse diameter of 4.0-4.5cm, and a weight of 40-45g.

3. The method for promoting seed germination and seedling emergence of garlic cloves according to claim 1, characterized in that: The drying bed in step (2) is 3m long, 1.2m wide, and 0.8m high above the ground. The drying net of the drying bed is a galvanized woven wire mesh with a mesh size of 10mm × 10mm.

4. The method for promoting seed germination and seedling emergence of garlic bulbs according to claim 1, characterized in that: In step (3), the grinding process is performed using a drum grinder.

5. The method for promoting seed germination and seedling emergence of garlic cloves according to claim 1, characterized in that: In step (4), the disinfection method is to soak the seeds in a 0.5% potassium permanganate solution for 2 hours or in a 5% sodium hypochlorite solution for 90 minutes; the gibberellin solution soaking method is to soak the seeds in a 200 mg / L gibberellin solution for 24 hours at a soaking temperature of 25°C.

6. The method for promoting seed germination and seedling growth of garlic cloves according to claim 1, characterized in that: The method of potassium permanganate disinfection in step (5) is to soak the sand in a 0.5% potassium permanganate solution for 1 hour, with the volume ratio of river sand to potassium permanganate solution being 1:

2.

7. The method for promoting seed germination and seedling growth of garlic cloves according to claim 1, characterized in that... The three-stage variable-temperature sand storage treatment in step (6) is as follows: the first stage is the initial low-temperature treatment, which lasts from day 1 to 30, and the temperature is constant at 4-5℃; the second stage is the mid-term high-temperature treatment, which lasts from day 31 to 75, with the temperature set at 25℃ from 5:00 to 21:00 every day and at 10℃ from 21:00 to 5:00 the next morning; the third stage is the final medium-temperature treatment, which lasts from day 76 to 90, and the temperature is constant at 22℃.

8. The method for promoting seed germination and seedling growth of garlic cloves according to claim 1, characterized in that... The preparation methods for disinfected river sand in steps (7) and (8) are as follows: disinfect with a 0.5% potassium permanganate solution, using 600 mL of 0.5% potassium permanganate solution per kg of river sand, stir evenly and let stand for 30 minutes, then add water to adjust the moisture content to 55%; or use an 800-fold diluted solution of 50% carbendazim wettable powder, using 3000 mL of 800-fold diluted solution of 50% carbendazim wettable powder per kg of river sand, stir evenly, cover with plastic film and let stand for 4 hours, remove the film and air dry for 2 days, then add water to adjust the moisture content to 55%.

9. The method for promoting seed germination and seedling growth of garlic bulbs according to claim 1, characterized in that: In step (8), sterilization is performed every 15 days using a 50% carbendazim wettable powder solution diluted 800 times. 3 Use 3L of diluted solution for the seedbed, spraying until the topsoil is thoroughly moistened without water accumulation.

10. The method for promoting seed germination and seedling growth of garlic cloves according to claim 1, characterized in that... The method for preparing the nutrient soil in step (9) is as follows: First, mix peat soil, fully decomposed sweet tea husks, perlite, and decomposed organic fertilizer in a weight ratio of 10:5:3:2 to obtain a mixture. Then, add 2 kg of powdered calcium magnesium phosphate fertilizer, 0.3 kg of ferrous sulfate, 50 g of 50% carbendazim wettable powder, and 40 g of 70% mancozeb wettable powder per m³ of the mixture. While stirring, spray water to make the moisture content reach 55%. After stirring evenly, cover with a film and pile up. It can be obtained in 7 days; or first, mix humus, fully decomposed sweet tea shells, perlite, and decomposed organic fertilizer in a weight ratio of 10:5:3:2 to obtain a mixture. Then, add 2 kg of powdered calcium magnesium phosphate fertilizer, 0.3 kg of ferrous sulfate, 0.1 kg of borax, 50 g of 50% carbendazim wettable powder, and 40 g of 70% mancozeb wettable powder per m³ of the mixture. While stirring, spray water to make the moisture content reach 55%. After stirring evenly, cover with a film and let it ferment for 7 days to obtain the final product.

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