A method for rapid propagation of Idesia polycarpa by cutting of one leaf and one bud

Abstract

The application discloses a kind of methods for quick propagation of Idesia polycarpa Maxim. tender branch one leaf one bud cutting, which uses the current year's non-lignified or semi-lignified branch of Idesia polycarpa Maxim. as the cutting mother branch; the cutting mother branch is pruned into one leaf one bud cutting; the cutting is inserted into the substrate under the conditions of high temperature, high humidity and high illumination; the rooting survival rate of Idesia polycarpa Maxim. one leaf one bud cutting can be stabilized to more than 87% by using the method, which is significantly better than the existing hardwood cutting method, and realizes the efficient, low-cost and rapid propagation of Idesia polycarpa Maxim. variety.

Description

Technical Field

[0001] This invention relates to the field of asexual reproduction technology of *Vernicia fordii*, specifically to a method for rapid propagation of *Vernicia fordii* by cuttings of tender branches with one leaf and one bud. Background Technology

[0002] *Idesia polycarpa* Maxim., also known as the mountain privet or oil grape, is a deciduous tree belonging to the genus *Idesia* in the family Elaeagnaceae. It is a woody oilseed tree species endemic to my country. Its fruits and seeds have an average oil content of up to 36.9%, with the refined oil containing over 80% unsaturated fatty acids and a high linoleic acid content of 63.9%. It is also rich in vitamin E, squalene, and polyphenolic compounds, exhibiting clear physiological regulatory functions in improving lipid metabolism, inhibiting the progression of atherosclerosis, and resisting oxidative stress. Furthermore, *Idesia polycarpa* has a well-developed lateral root system, providing excellent soil and water retention capacity; its upright crown and persistent, clustered fruits that last for several months offer significant landscape benefits; its timber can be used in construction and furniture making; and its oil extraction byproduct, the cake, is rich in crude protein and can be used as high-quality feed or organic fertilizer. Therefore, vigorously promoting the cultivation of *Idesia polycarpa* has significant economic and ecological value.

[0003] Currently, there are many shortcomings in the propagation methods of *Vernicia fordii*. While seed propagation is simple and inexpensive, *Vernicia fordii* is dioecious, requiring seedlings to grow for 4-5 years before sex can be determined, and the offspring exhibit significant phenotypic segregation, making it difficult to maintain the superior characteristics of the parent plant and limiting the efficiency of establishing high-yield oilseed forests. Tissue culture has a high propagation coefficient, is not limited by season, and can ensure uniform seedlings and controllable sex, but it faces problems such as difficulty in explant sterilization, severe tissue browning, and low transplant survival rates. Furthermore, it requires specialized equipment and technicians, resulting in high production costs and making it difficult to promote its application in ordinary production entities. Grafting propagation can maintain superior traits, but it carries the risk of rootstock-scion incompatibility and growth disorder, has high management costs and technical barriers, and is not suitable for large-scale rapid seedling production.

[0004] Cutting propagation, as an important method of asexual reproduction, allows for the selection of female plants of known sex as mother plants for cuttings, thus identifying the sex from the source. It is also relatively simple and cost-effective. Existing technologies include research on cutting methods for *Vernicia fordii*. For example, Chinese patent application CN202111285678.5 discloses a method for hardwood cutting propagation of *Vernicia fordii* using 1-2 year old branches that have undergone sand stratification before cutting. A quick dip in a mixture of willow branch water and honey promotes rooting. Another example is Chinese patent (publication number CN113853963A), which relates to hardwood cutting technology for *Vernicia fordii*, improving the rooting rate through steps such as mother plant selection, sand stratification, and seedbed preparation. Tang Zixuan et al.'s paper, "On the Cutting Propagation Techniques of *Vernicia fordii*", shows that the rooting rate of cuttings taken in late October can reach 68.33%–76.67%, while Tan Qin's research, "Discussion on the Breeding and Cultivation Techniques of *Vernicia fordii*", shows that the rooting rate of hardwood cuttings taken in spring is only 30.00%–36.70%. However, the existing long-branch multi-bud cutting method has shortcomings such as low utilization rate of cuttings, dispersed nutrients, unstable rooting rate, and great influence from seasons and environment.

[0005] Chinese patent (application number CN202311599214.0) discloses a method for improving the survival rate of *Vernicia fordii* cuttings. This method involves mixing vermiculite, river sand, and promoter I as the cutting substrate, and then quickly dipping the cuttings in a mixture of promoter II to inhibit polyphenol browning and reduce the rot rate. However, this method still uses existing multi-bud cuttings pruned from one-year-old lignified branches to a length of 8-10 cm, resulting in limited cutting utilization and limitations imposed by the degree of lignification of the branches and the harvesting season.

[0006] In summary, current asexual propagation techniques for *Vernicia fordii* have not yet formed a mature system that balances high efficiency, low cost, ease of promotion, and gender control, thus hindering the large-scale development of the *Vernicia fordii* industry. Therefore, exploring a seedling cultivation method with a high propagation coefficient, simple operation, high branch utilization rate, rapid rooting, no slow seedling period, and clear gender control is of great significance for the promotion of improved varieties of *Vernicia fordii*. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, solving the technical problems of low cutting utilization, long rooting cycle, severe seasonal limitations, and insufficient propagation coefficient in existing *Vernicia fordii* cutting techniques.

[0008] To achieve the above objectives, the following technical solution is adopted:

[0009] A method for rapid propagation of *Vernicia fordii* by cuttings of young branches with one leaf and one bud includes the following steps:

[0010] (1) Collection and preparation of cuttings: During the growing season of *Vernicia fordii*, select healthy, vigorous, and plump current-year non-lignified or semi-lignified branches as mother branches for cuttings; prune the mother branches into one-leaf-one-bud cuttings (i.e., the mother branches are short cuttings, i.e., the mother branches retain only one plump bud and one leaf), make a horizontal cut 0.5-1.5cm above the bud at the top, and make a slanted cut 1-2cm below the bud at the back of the bud at the bottom, with the cuts smooth and not split, retain one bud and one leaf, and cut off 1 / 3 to 1 / 2 of the leaf; the core purpose of leaf pruning is to reduce transpiration and water loss from the bud and leaf area under the premise of ensuring basic photosynthesis, to inhibit bud and leaf development, so that the nutrients stored in the cutting are used for rooting first, and to make the overall center of gravity of the cutting closer to the main stem of the cutting, so that the cutting will not tip over when lightly inserted later.

[0011] (2) Treatment of cuttings: The cuttings obtained in step (1) are quickly dipped in a rooting promoter solution, wherein the rooting promoter is ABT rooting powder solution;

[0012] (3) Preparation of cutting substrate: Mix peat, coconut coir and perlite evenly in proportion, disinfect with disinfectant, and add Burkholderia gladioli CT-5 bacterial agent (refer to CN202510635816.X "Burkholderia gladioli and its application" for this bacterial agent);

[0013] (4) Cuttings: Insert the cuttings treated in step (2) into the cutting substrate prepared in step (3). The insertion depth should only be such that the cuttings can stand upright. This method avoids the required insertion depth specified in existing technologies, which places higher demands on the operator's precision. At the same time, if the cuttings are inserted too deeply, and the root system has not yet formed, the part of the cutting that penetrates into the substrate is prone to partial "necrosis" due to prolonged contact with the substrate. Furthermore, the cuttings are prone to breakage or mechanical wear on the outer layer of the cutting stems during the insertion process, resulting in a low survival rate of the cuttings and insufficient nutrient or water transport efficiency in the later stages. With this technology, it is only necessary for the rooting end of the cutting to be in full contact with the substrate and to ensure that the cutting does not fall over.

[0014] (5) Post-cutting management: After cutting, water thoroughly to settle the roots. Control the ambient temperature to 20-28℃, the air humidity to 75%-90%, and the light intensity to 60%-80% of natural light. Use a misting system to maintain the humidity range of the substrate at the cutting site. Observe and replenish water regularly. The ambient temperature is regulated by a temperature control system, the air humidity is regulated by a humidity control device, and the light intensity is regulated by a lighting device.

[0015] (6) Transplanting: After the cuttings have taken root, transplant the rooted seedlings to the field or into nutrient pots for further cultivation.

[0016] Furthermore, half of the leaf blade described in step (1) is cut off.

[0017] Furthermore, the concentration of the ABT rooting powder solution in step (2) is 800-1000 mg / L, and the dipping time is 1-10 s.

[0018] Furthermore, the concentration of the ABT rooting powder solution is 1000 mg / L, and the dipping time is 1-3 seconds. When using softwood cuttings, the concentration should not exceed 1000 mg / kg for quick dipping, as excessive concentration will burn the buds and cause browning of the cut. The quick dipping method avoids browning of softwood cuttings and solves the problem of slow rooting of short softwood cuttings.

[0019] Furthermore, the mass ratio of peat, coconut coir, and perlite in step (3) is (4-6):(2-4):(1-3).

[0020] Furthermore, the mass ratio of peat, coconut coir, and perlite is 5:3:2; coconut coir provides a lightweight fibrous structure, balancing water retention and air permeability, which is suitable for the shallow planting of short cuttings and solves the problem of balancing substrate air permeability and water retention.

[0021] Furthermore, the disinfectant in step (3) is prepared by diluting 30-50g of Emu-Neng with 100kg of water.

[0022] Furthermore, the amount of Burkholderia gladioli CT-5 bacterial agent added in step (3) is 500-800 times the concentration.

[0023] Furthermore, the amount of the Burkholderia gladioli CT-5 bacterial agent added is 500 times the concentration.

[0024] Furthermore, the spacing between cuttings in step (4) is 8-12cm × 8-12cm.

[0025] Furthermore, the ambient temperature in step (5) is 22-26℃, the air humidity is 80%-85%, and the light intensity is 70%-75%.

[0026] Furthermore, in step (5), ventilation is carried out 7-10 days after the cuttings are inserted.

[0027] Furthermore, the timing of transplanting in step (6) is when the number of roots of the cuttings reaches more than 30 and the seedling height is 30-50cm.

[0028] Compared with the prior art, the present invention has the following technical principles and beneficial effects:

[0029] This invention proposes a highly efficient cutting propagation method for *Vernicia fordii* based on the "one leaf, one bud" principle. Compared with existing technologies, its basic technical principles and beneficial effects are as follows:

[0030] 1. Concentrated nutrient supply significantly improves rooting rate.

[0031] This invention uses single-bud, single-leaf cuttings. The nutrients stored within the cutting do not need to be dispersed among multiple buds (existing cutting techniques generally use 2-6 buds to ensure survival rates), but are instead concentrated on a single rooting and germination site. Simultaneously, because the cutting length is only 1 / 5 to 1 / 3 of existing cuttings, auxin is rapidly transported to the base over a short distance, resulting in faster rooting and seedling growth.

[0032] Experiments show that callus tissue can form 4 to 6 days after cutting, and roots can begin to grow in 7 to 8 days, which is significantly shorter than the rooting cycle of more than 30 days for existing hardwood cuttings. Each bud becomes an independent apical meristem. After single-bud cuttings germinate, the main stem grows vigorously and in a consistent direction, resulting in a naturally regular plant shape. This avoids the problem of disordered plant shape caused by multiple branches after the seedlings are grown from multi-bud cuttings (when multiple buds are retained in the cutting, multiple buds tend to germinate simultaneously after the cuttings survive, resulting in a plant shape with multiple branches and a slanted, scattered crown. If the budding lateral buds are not controlled, the distribution of branches and trunks of the seedlings will be messy, the plant will have poor uprightness, the transplanting operation will be more difficult, and it will further induce excessive tilting and breakage of branches, leading to fluctuations in transplant survival rate; at the same time, the inconsistent differentiation of tree shape will directly lead to a decrease in the stability of fruiting traits and fruit quality in the later stage. If pruning is used to remove excess buds and only a single main trunk is retained, the remaining main trunk is still prone to tilting growth due to the original bud position tilt and the inertia of branch growth, making it difficult to cultivate upright seedlings.

[0033] This method utilizes one leaf and one bud cuttings, ensuring each bud becomes an independent apical meristem, resulting in strong and uniform main stem growth after sprouting. This fundamentally avoids the problem of disordered plant shape caused by the simultaneous sprouting and competitive growth of multiple buds in existing multi-bud cuttings. Practice has shown that even after pruning to remove excess shoots, the remaining main stem of multi-bud seedlings is still prone to tilting due to the original bud position and growth inertia, making it difficult to cultivate upright seedlings and easily leading to fluctuations in transplant survival rates and a decline in fruit quality later on. However, the seedlings cultivated using this method naturally disappear as the cutting reaches a diameter of 1-2 cm, allowing the original cutting and new branches to form an independent, upright tree that is naturally neat and requires no complex correction, significantly improving the standardization and transplant adaptability of the seedlings.

[0034] 2. Increased reproduction rate, enabling efficient propagation.

[0035] Existing multi-bud cuttings can only produce 2-4 cuttings per branch, while one-leaf-one-bud cuttings increase the propagation coefficient of a single branch by 3-5 times (i.e., the original technique requires multiple buds for cuttings, and the cutting length is mostly 6-15cm, resulting in only a small number of cuttings from the same branch). Based on an average of 8-10 effective buds per one-year-old branch, 8-10 one-leaf-one-bud cuttings can be prepared, while existing methods can only produce 2-3 cuttings 8-10cm long. This significantly improves propagation efficiency and effectively solves the problem of high-quality seedling supply shortage.

[0036] 3. The short-branch structure, combined with the misting system, allows for precise and controllable water management.

[0037] Existing long cuttings (6-15cm) have long vascular pathways, resulting in high resistance to water transport. The upper part of the cutting is prone to wilting due to transpiration and water loss (due to the presence of multiple buds). This invention uses short cuttings with shorter vascular pathways, lower resistance to water transport, and only a single bud (reducing transpiration and water loss). Combined with a misting system to precisely maintain water balance, it can effectively prevent cuttings from drying out and dying. At the same time, the planting depth only needs to ensure that the cutting is upright, without the need for deep planting (based on practical experience, a planting depth of 0.5-1cm is sufficient), reducing the risk of mechanical damage when planting tender branches. This greatly reduces the precision requirements and workload for planting personnel. In other words, the cutting-type short stem segment cutting + shallow planting method of this invention significantly shortens the polar transport distance of auxin; nutrients are concentrated and supplied to a single rooting site; and mechanical damage to tender branches is reduced, solving the problems of long rooting cycles (>30 days) and significant operational damage.

[0038] 4. Biological agents control root rot, overcoming the drawbacks of high humidity environments.

[0039] While high temperature, high humidity, and abundant sunlight are beneficial for rooting cuttings (high temperature, high humidity, and abundant sunlight are the core requirements of the technical effectiveness of this application; abundant sunlight promotes leaf photosynthesis, providing the organic carbon source and energy needed for rooting of short cuttings, accelerating callus formation, and solving the problems of insufficient nutrient storage and insufficient rooting power in short cuttings; abundant humidity ensures that cuttings can achieve water supply in the early stage when callus tissue and roots are not fully developed), it can also easily induce the proliferation of pathogens in the substrate, leading to root rot. This invention adds Burkholderia gladioli CT-5 inoculant to the substrate. This strain can effectively prevent root rot and promote plant growth, overcoming the technical challenge of high incidence of soil-borne diseases under high humidity management and ensuring the stability of cutting survival rate.

[0040] 5. Multiple production batches throughout the year, breaking seasonal limitations.

[0041] By using current-year non-lignified or semi-lignified tender branches in conjunction with controlled greenhouse environments, precise control of temperature and light can be achieved, allowing cuttings to be propagated without seasonal limitations. This results in 5-15 batches of propagation per year, significantly improving land and facility turnover efficiency. The industrialization threshold is low, enabling large-scale production by ordinary farmers.

[0042] 6. Purely asexual reproduction, with precise and controllable sex.

[0043] Single-bud cuttings are a form of asexual reproduction, preserving all the genetic traits of the mother plant. The sex of *Vernicia fordii* is controlled by a fixed genotype in somatic cells. Cuttings, as clones of the mother plant, allow for precise sex determination of offspring in the early stages of seedling cultivation, completely resolving the drawback of random sex separation in seedlings and the generation of numerous male plants with no fruit-bearing value.

[0044] 7. Well-developed root system, no slow seedling establishment period

[0045] The root system formed by a single-leaf, single-bud cutting consists of adventitious roots with dense and well-developed fibrous roots. After planting, the root system can immediately absorb water and nutrients from the soil, and the above-ground growth continues uninterrupted, completely avoiding the stagnation period commonly found in grafted and transplanted seedlings. Fruiting can begin 2-3 years after planting, 2-4 years earlier than seedlings grown from seed, significantly shortening the investment return cycle.

[0046] 8. The manual process is simple, greatly saving labor costs.

[0047] Compared with existing grafting techniques and general cutting techniques, this method does not require high technical skills from operators in handling and inserting cuttings. The only requirements of this application are high environmental and substrate pest and disease control (especially root rot), which greatly reduces the labor intensity of personnel in the later management part, making it particularly suitable for large-scale development in greenhouse-style stable environmental conditions.

[0048] In summary, the various conditions and requirements in this technical solution form a closed-loop technology system.

[0049] The water balance problem is solved by combining multiple lighting to promote photosynthesis with a fogging system for precise water replenishment; the Burkholderia gladioli CT-5 bacterial agent is a specific strain, and its application is based on CN202510635816.X. Therefore, the introduction of the Burkholderia gladioli CT-5 bacterial agent is a targeted solution to the unique technical contradictions of this invention; the role of coconut coir in this invention is to provide lightweight support in conjunction with shallow planting (F9), which is compatible with the physical characteristics of short cuttings and has a specific functional correlation.

[0050] The detailed technical closed-loop process of this application is as follows:

[0051] This application requires a short branch + one bud + one leaf + a cutting suitable for shallow planting (advantages include concentrated nutrients, reduced damage, and rapid propagation in multiple batches regardless of season; however, the cutting requires a special environment) – a high temperature, high humidity, and high light environment (advantages include promoting photosynthesis, even and abundant water distribution, and providing energy for rooting; however, the disadvantage is that this environment may induce the proliferation of pathogens in the substrate) – Burkholderia gladioli CT-5 inoculant + coconut coir substrate (advantages include prevention of root rot, good substrate aeration to ensure root health, and suitability for shallow planting; disadvantages include low substrate moisture and nutrient retention and stability) – a misting system + ABT quick dip (precise watering, external hormones to promote rapid rooting). The results, as shown in the experimental results, indicate that using the method of this invention, the rooting survival rate of one-leaf-one-bud cuttings of *Vernicia fordii* can stably reach over 87%, significantly better than existing hardwood cutting methods, achieving efficient, low-cost, and rapid propagation of superior *Vernicia fordii* varieties.

[0052] The present invention has achieved the following unexpected technical effects:

[0053] Effect 1: A qualitative change in rooting speed

[0054] The rooting time has been shortened from more than 30 days to 7-8 days, which is about 80% shorter than the existing technology (30-50 days). This is a significant improvement that is a qualitative change resulting from quantitative change.

[0055] Effect 2: Combining survival rate and disease prevention

[0056] In the "high-risk" environment of high temperature, high humidity and high lighting, the incidence of root rot was significantly reduced by using Burkholderia gladioli CT-5 inoculant, while maintaining a survival rate of over 90%, overcoming the irreconcilable contradiction between "high humidity promotes root growth" and "high humidity causes disease" as currently understood.

[0057] Effect 3: Reproduction coefficient jumps.

[0058] The propagation coefficient of a single mother branch has increased from 2–3 times to 8–10 times, an increase of 3–5 times, effectively solving the bottleneck of supply of high-quality seedlings.

[0059] Effect 4: No transplant shock period

[0060] The transplant survival rate is about 92%, and the seedlings grow normally after transplanting. The seedling height increases by 8-12cm in 30 days, which is far better than the relevant growth data and survival rate disclosed in existing technical solutions.

[0061] It should be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of the present invention, nor is it intended to restrict the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0062] The above and other features, advantages, and aspects of the various embodiments of the present invention will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the invention and are not intended to limit the scope of the invention. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0063] Figure 1 This is a diagram showing the callus formation and rooting status of the cuttings 5 ​​days after cutting in Example 1 of the present invention.

[0064] Figure 2 This is a diagram showing the rooting status of the cuttings two weeks after cutting in Example 1 of the present invention;

[0065] Figure 3 This is a diagram showing the growth status of seedlings one month after cutting in Example 1 of the present invention.

[0066] Figure 4 This is a diagram showing the growth status of seedlings two months after cutting in Example 1 of the present invention;

[0067] Figure 5 This is a schematic diagram of the cutting depth in Embodiment 1 of the present invention;

[0068] Figure 6-9 This is a statistical chart showing the data on water content and oil content of multiple batches of *Vernicia fordii* fruit at different stages in Example 1;

[0069] Figure 10-13 The image shows the physicochemical test report of the fruit of *Vernicia fordii* in Example 1. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0071] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0072] I. This application includes four specific embodiments and three comparative embodiments, as detailed below;

[0073] Example 1

[0074] 1. Collection and preparation of cuttings

[0075] In early June 2025, at a high-quality tung tree seed base in a mountainous area of ​​Guizhou Province, female trees that were over 5 years old and had been bearing fruit stably for 3 consecutive years were selected as mother trees for scion collection. On a sunny morning, non-lignified or semi-lignified branches from the upper part of the mother trees, which were free from pests and diseases, vigorous, with plump buds and a diameter of 0.3-0.8 cm, were selected as mother branches for scion collection.

[0076] Wrap the collected mother branches in a damp cloth to retain moisture and quickly bring them back to the processing greenhouse. Cut the branches into one-leaf-one-bud cuttings. Make a horizontal cut 1.5cm above the bud at the top, and a slanted cut 2cm below the bud at a 45° angle (opposite to the direction of bud growth). Ensure the cuts are smooth, without splitting or tearing the bark. Each cutting should retain one plump bud and one intact leaf. Trim the leaf in half with clean scissors to reduce transpiration. Immediately place the cut cuttings in clean water to maintain moisture until needed.

[0077] 2. Treatment of cuttings

[0078] To prepare a 1000 mg / L ABT rooting powder solution: Weigh 1 g of ABT rooting powder (No. 1), dissolve it thoroughly in a small amount of 75% alcohol, then dilute it to 1 L with distilled water and stir well.

[0079] Dip the lower end (oblique cut end) of the prepared one-leaf-one-bud cutting into the ABT solution for 2 seconds, remove it and let it dry slightly before use.

[0080] 3. Preparation of the cutting substrate

[0081] Peat, coconut coir, and perlite were mixed evenly in a mass ratio of 5:3:2 to obtain a composite matrix. A disinfectant solution was prepared by diluting 35g of Emu-Nutrient in 100kg of water. The composite matrix was sprayed with the disinfectant solution until evenly moistened, and then covered with plastic film for 24 hours for disinfection.

[0082] After disinfection, add 500 times diluted Burkholderia gladioli CT-5 bacterial agent to the substrate, stir well, and make the effective viable bacteria count in the substrate reach more than 2×10^8 CFU / g.

[0083] Fill the prepared substrate into 50-cell seedling trays, press lightly to flatten, and set aside.

[0084] 4. Cuttings

[0085] Insert the prepared cuttings into the substrate, ensuring the cuttings stand upright. The spacing between plants should be approximately 8cm x 8cm. When inserting the cuttings, ensure the lower cut (rooting end) is in close contact with the substrate, avoiding any gaps.

[0086] 5. Post-cutting management

[0087] Immediately after cutting, water thoroughly to settle the roots, ensuring the substrate is fully moistened and in close contact with the base of the cutting.

[0088] Control environmental conditions: maintain temperature at 23-25℃, relative humidity at 80%-85%, and light intensity at approximately 70% of natural light. Use a misting system to spray for 15 seconds every 30 minutes during the day to maintain humidity.

[0089] Seven days after cutting, callus tissue began to form. At this time, ventilation was started twice a day, morning and evening, for 30 minutes each time. Twelve days after cutting, adventitious roots began to sprout. Starting 15 days after cutting, a mixture of 0.2% potassium dihydrogen phosphate solution and amino acid water-soluble fertilizer (diluted 800 times) was sprayed on the leaves once a week.

[0090] 6. Transplanting

[0091] Thirty days after cutting, the average number of roots on the cuttings should reach more than 30, and the seedlings should be 15-20cm tall with well-developed root systems that have penetrated the bottom of the seedling tray. Then increase ventilation and light intensity, and transplant them to the field or seedling cups after 7 days.

[0092] After transplanting, water thoroughly to help the roots establish, and then manage as usual.

[0093] Example 2

[0094] The difference between this embodiment and Embodiment 1 is that:

[0095] In step 1, select cuttings with a diameter of 0.8-1.2cm, make a slanted cut 2cm below the bud on the back of the bud, and cut off 1 / 3 of the leaves.

[0096] In step 2, the cuttings are first disinfected in a 0.2% potassium permanganate solution for 30 minutes, and then rinsed with clean water. Afterwards, the lower end of the cutting is quickly dipped in a 2000 mg / L IBA solution for 10 seconds, and then removed for later use.

[0097] In step 3, peat, coconut coir, and perlite are mixed in a mass ratio of 4:4:2.

[0098] The remaining steps are the same as in Example 1.

[0099] Example 3

[0100] The difference between this embodiment and Embodiment 1 is that:

[0101] In step 1, the cutting time is in mid-July. Select current-year non-lignified or semi-lignified branches with a diameter of 0.5-1.0cm. Make a slanted cut on the back of the bud 1.5cm below the bud, and cut off 1 / 2 of the leaves.

[0102] In step 2, an 800 mg / L ABT rooting powder solution was used, and the treatment time was 3 seconds.

[0103] In step 3, peat, coconut coir, and perlite are mixed in a mass ratio of 6:2:2. The dosage of Emu-N is 40g / 100kg water, and the dosage of Burkholderia gladioli CT-5 bacterial agent is 800 times diluted.

[0104] In step 5, the air temperature is controlled at 22-26℃, the humidity is maintained at 78%-85%, and the light intensity is 65%-75% of natural light.

[0105] The remaining steps are the same as in Example 1.

[0106] Example 4

[0107] The difference between this embodiment and Embodiment 1 is that:

[0108] In step 1, the cuttings are collected in early August. The lower cut of the cutting is made obliquely 1cm below the bud on the back of the bud, and 1 / 3 of the leaves are cut off.

[0109] In step 2, a 1200 mg / L ABT rooting powder solution was used, and the treatment time was 1 second.

[0110] In step 3, 30g of Emu-Nutrient per 100kg of water is used for disinfection.

[0111] In step 5, ventilation should begin 8 days after cutting, and rooting should be observed 11 days after cutting. The air temperature should be controlled at 20-28℃ and the humidity at 75%-90%.

[0112] The remaining steps are the same as in Example 1.

[0113] Comparative Example 1 (Comparison of different scion specifications)

[0114] Compared with Example 1, the only difference is the size of the cuttings.

[0115] This comparative example uses existing multi-bud cuttings: take the same batch of mother branches, prune them into cuttings 15cm long with 2-4 buds, make a flat cut at the top and a slanted cut at the bottom, retain 1-2 leaves at the top (cut off 1 / 2), dip the cuttings quickly in ABT solution for 10 seconds, and insert them to a depth of not less than 10cm.

[0116] The rooting promoter, substrate formulation, management conditions, and statistical methods were the same as in Example 1.

[0117] After 30 days of propagation, the rooting rate of the one-leaf-one-bud cuttings in Example 1 reached 84%-92%, while the rooting rate of the multi-bud cuttings in this comparative example was only 55%-65%, and the rooting time was 10-15 days later than that in Example 1.

[0118] Comparative Example 2 (Comparison of different matrix formulations)

[0119] Compared with Example 1, the only difference is that Burkholderia gladioli inoculant was not added to the matrix, while the other conditions were the same as in Example 1.

[0120] Observation 25 days after cutting: the cuttings of Example 1 showed no root rot and the plants grew vigorously; about 15% of the cuttings in this control group showed root rot, which manifested as browning and rotting at the base and wilting of the leaves.

[0121] Comparative Example 3 (Comparison of different scion lengths)

[0122] In contrast to Example 1, the difference lies in the length of the cuttings.

[0123] This comparative example uses cuttings with one leaf and one bud, each 7-8 cm long (with the lower cut 4-5 cm below the bud), and the insertion depth is no less than 2.5 cm. Other conditions are the same as in Example 1.

[0124] The results showed that the short cuttings (2cm) in Example 1 began to root 12 days after insertion, while the long cuttings (7-8cm) in this comparative example only began to root 18 days after insertion, and the rooting rate was about 10-15 percentage points lower than that in Example 1. This indicates that excessively long cuttings are not conducive to concentrated nutrient supply and water transport.

[0125] II. The comparison of data from each experiment is as follows:

[0126] 1. Statistics on the number of cuttings that rooted (only Example 1 was included in the statistics)

[0127] Following the method in Example 1, softwood cuttings of *Vernicia fordii* were used for propagation. Fifty cuttings were used to count the number of roots formed from cutting to 20 days after cutting. The experiment showed that callus tissue could be formed in 5-6 days after cutting and roots could be formed in 7-8 days. This was significantly shorter than the rooting cycle of more than 30 days for existing hardwood cuttings. The results are shown in Table 1.

[0128] Table 1. Statistics on the number of roots formed from cuttings (only for the method in Example 1)

[0129]

[0130] 2. Cuttings survival rate statistics

[0131] The softwood cuttings of *Vernicia fordii* were propagated by means of Examples 1-4 and Comparative Examples 1-3, with 100 cuttings per group and three replicates. The rooting and survival rate of the cuttings 45 days after propagation was statistically analyzed, and the results are shown in Table 2.

[0132] Table 2. Survival rate of *Vernicia fordii* cuttings under different treatments

[0133]

[0134] Results analysis:

[0135] (1) The survival rate of Examples 1-4 was all above 87%, which was significantly higher than that of the existing multi-bud cuttings of Comparative Example 1 (62%), indicating that the one-leaf-one-bud cutting technology of the present invention can significantly improve the survival rate of *Vernicia fordii* cuttings.

[0136] (2) The rooting time of Examples 1-4 was 7-13 days, which was significantly shorter than the 28 days of Comparative Example 1 and the 18 days of Comparative Example 3, indicating that the treatment of short cuttings with appropriate rooting promoters can significantly accelerate the rooting process.

[0137] (3) The survival rate of Comparative Example 2 (77%) was lower than that of Example 1 (92%), but significantly higher than that of Comparative Example 1 (62%). This indicates that adding Burkholderia gladiolus can effectively control root rot and improve the survival rate. However, even without adding the fungicide, the survival rate of the one-leaf-one-bud cutting itself is still better than that of the existing multi-bud cuttings.

[0138] (4) The survival rate of Comparative Example 3 (77%) was lower than that of Example 1, indicating that excessively long cuttings are not conducive to nutrient concentration and water transport, thus affecting rooting efficiency.

[0139] 3. Comparison of reproduction coefficients

[0140] Following the cutting preparation methods of Example 1 and Comparative Example 1, the number of cuttings prepared from a single mother branch (based on 10 effective buds and a length of 50cm) and the propagation efficiency were calculated, and the results are shown in Table 3.

[0141] Table 3 Comparison of propagation coefficients for different cutting specifications

[0142]

[0143] The results showed that by using the "one leaf, one bud" method of the present invention, the propagation coefficient of a single mother branch is 8-10 times, which is 3-5 times higher than the 2-3 times of the existing method, and can greatly improve the propagation efficiency of improved seedlings.

[0144] 4. Transplant survival rate and growth performance

[0145] The rooted cuttings of Example 1 and Comparative Example 1 were transplanted to the field and managed in a routine manner. The survival rate and growth status were recorded 30 days after transplanting. The results are shown in Table 4.

[0146] Table 4. Growth performance of cuttings after transplanting under different treatments

[0147]

[0148] The results showed that the one-leaf-one-bud cuttings cultivated using the method of this invention had dense and well-developed fibrous roots, exhibited almost no slow-growth period after transplanting to the field, and grew normally immediately after transplanting. Their growth rate after planting was significantly better than that of seedlings cultivated using existing methods. The above description is merely a preferred embodiment of the present invention and is used only to explain the invention. It is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

[0149] In addition, our researchers randomly divided batches of the mature *Vernicia fordii* fruits obtained in Example 1 to determine their composition (see details). Figure 6-9 We conducted multiple batches of tests at different time periods to measure the relevant data such as water content and oil content of the corresponding *Vernicia fordii* fruits, as well as physicochemical tests (see details). Figure 10-13 The test results were obtained by Guizhou Shuanghao Ecological Agriculture Development Co., Ltd. during the implementation of our planting technology. They were commissioned to conduct relevant physicochemical tests on the third party. The results were not significantly different from those of wild tung oil trees. Therefore, we believe that this planting method can be rapidly and mass-produced.

[0150] It should also be noted that, in the embodiments of this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0151] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined in the embodiments of this application may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown in this application, but is to be accorded the widest scope consistent with the principles and novel features disclosed in the embodiments of this application.

Claims

1. A method for rapid propagation of *Vernicia fordii* by cuttings of tender branches with one leaf and one bud, characterized in that: The current year's non-lignified or semi-lignified branches of *Vernicia fordii* were used as mother branches for sapling collection; The mother branches for cuttings are pruned into short cuttings with one leaf and one bud, meaning that only one plump bud and one leaf are retained on the mother branches for cuttings. The cuttings are gently inserted into the substrate under conditions of high temperature, high humidity, and multiple lighting.

2. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud as described in claim 1, characterized in that... The high temperature and high humidity, as well as multiple lighting conditions, refer to: The ambient temperature should be controlled at 20-28℃, the air humidity at 75%-90%, and the light intensity at 60%-80% of natural light.

3. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud as described in claim 1, characterized in that... The matrix includes: Calculated by weight parts Peat: 4-6 parts; Coconut coir: 2-4 parts; Perlite: 1-3 parts.

4. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud as described in claim 1, characterized in that: To overcome the problem of root rot in plants caused by high temperature, high humidity and multiple lighting conditions, Burkholderia gladioli CT-5 inoculant was added to the substrate.

5. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, as described in any one of claims 1-4, is characterized in that... Includes the following steps: Step 1: During the growing season of *Vernicia fordii*, select healthy, vigorous, and plump current-year non-lignified or semi-lignified branches as mother branches for cuttings; prune the mother branches into cuttings with one leaf and one bud, making a horizontal cut 0.5-1.5cm above the bud at the top and a slanted cut 1-2cm below the bud at the bottom, ensuring the cuts are smooth and do not split, and retain one bud and one leaf; Step 2; Treatment of cuttings: Dip the cuttings obtained in Step 1 into a rooting accelerator solution for quick dipping treatment. The rooting accelerator is ABT rooting powder solution. Step 3; Preparation of cutting substrate: Mix peat, coconut coir and perlite evenly in proportion, disinfect with disinfectant, and add Burkholderia gladioli CT-5 bacterial agent; Step four; Cuttings: Insert the cuttings treated in step two into the cutting substrate prepared in step three; Step 5; Post-cutting management: After cutting, water thoroughly to settle the roots, use a misting system to maintain the humidity of the substrate at the corresponding cutting site, observe and replenish water regularly, and control the environmental conditions under the high temperature, high humidity and multiple lighting conditions mentioned above. Step Six; Transplanting: After the cuttings have taken root, transplant the rooted seedlings to the field or into nutrient pots for further cultivation.

6. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, as described in claim 5, is characterized in that: In step one, after pruning the single bud leaves on the cutting, only 1 / 2 to 2 / 3 of the leaf area is retained.

7. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, as described in claim 5, is characterized in that: In step two, the concentration of the ABT rooting powder solution is 800-1000 mg / L, and the dipping time is 1-10 seconds.

8. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, as described in claim 5, is characterized in that: In step three, the disinfectant solution is prepared by diluting 30-50g of Emu-Neng with 100kg of water; the amount of Burkholderia gladioli CT-5 bacterial agent added is 500-800 times dilution.

9. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, as described in claim 5, is characterized in that: The spacing between cuttings in step four is 8-12cm × 8-12cm; In step five, ventilation should be carried out 7-10 days after the cuttings are inserted. The timing for transplanting in step six is ​​when the cuttings have more than 30 roots and the seedlings are 30-50cm tall.

10. The method for rapid propagation of *Vernicia fordii* by cuttings with one leaf and one bud, as described in claim 5, is characterized in that: In step four, the insertion depth should be such that the cutting can stand upright in the substrate.

Images