A rooting agent for promoting rooting of young branch cuttage of cyclocarya paliurus and a seedling raising method

Abstract

This invention relates to a rooting agent and seedling cultivation method for promoting rooting of *Cyclocarya paliurus* cuttings, belonging to the field of plant asexual reproduction technology. It solves one of the problems in existing *Cyclocarya paliurus* seedling cultivation: low rooting rate, long rooting time, few and poor-quality adventitious roots, and low transplant survival rate. This invention discloses a rooting agent for promoting rooting of *Cyclocarya paliurus* cuttings, which consists of two components, A and B. Component A consists of potassium indolebutyrate, soluble starch, chlorogenic acid, salicylic acid, and talc; component B consists of indolebutyric acid, sucrose, chlorogenic acid, vitamin C, and talc. Using the above-mentioned rooting agent and the corresponding seedling cultivation method, rapid rooting of *Cyclocarya paliurus* cuttings is achieved, with a rooting rate as high as 93.06%, and a large number and good quality of adventitious roots, resulting in a transplant survival rate of 90.37%.

Description

Technical Field

[0001] This invention relates to the field of plant asexual reproduction technology, and in particular to a rooting agent and seedling cultivation method for promoting rooting of tender cuttings of Eucommia ulmoides. Background Technology

[0002] *Cyclocarya paliurus (Batalin) Iljinsk* is a monotypic genus endemic to my country, a precious tree species with multiple values ​​including medicinal, health-promoting, timber, and ornamental uses. Existing *Cyclocarya paliurus* resources mainly originate from natural forests, but are limited in quantity and scattered in distribution. Furthermore, these natural forests have suffered severe damage, hindering the development and industrialization of *Cyclocarya paliurus*. In addition, *Cyclocarya paliurus* seeds exhibit deep dormancy due to mechanical binding of the seed coat and inhibition by endogenous substances, typically requiring one to two years to germinate. Moreover, the proportion of empty seeds is high, resulting in an extremely low natural germination rate, severely limiting sexual reproduction and impacting its resource development.

[0003] With the promotion of improved varieties of Cyclocarya paliurus leaf-producing plantations, research on vegetative propagation technology has become a key technical issue that urgently needs to be addressed in the development of Cyclocarya paliurus leaf-producing forestry industry. Currently, vegetative propagation technology for Cyclocarya paliurus mainly relies on grafting, but the grafting survival rate is low and the propagation coefficient is small, making it difficult to meet the seedling needs of large-scale plantation cultivation. In terms of tissue culture seedling propagation, although progress has been made and the propagation coefficient has improved, the problems of low rooting rate and transplant survival rate still exist.

[0004] Eucommia ulmoides is a tree species that is difficult to root by cuttings. It has a low rooting rate, few adventitious roots, poor quality of adventitious roots (short root length), and mainly consists of fleshy roots with few lateral roots, resulting in a low survival rate after transplanting. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide a rooting agent and a seedling cultivation method for promoting the rooting of tender branches of *Cyclocarya paliurus*, in order to solve one of the problems in the existing technology of *Cyclocarya paliurus* tender branch seedling cultivation, especially in the process of cutting seedling cultivation, such as low rooting rate, long rooting time, few and poor quality adventitious roots (mostly fleshy roots), and low transplant survival rate.

[0006] This invention discloses a rooting agent for promoting rooting of tender cuttings of Eucommia ulmoides. The rooting agent is composed of two components, component A and component B. Component A consists of potassium indolebutyrate, soluble starch, crotonin, salicylic acid, and talc. Component B consists of indolebutyric acid, sucrose, crotonin, vitamin C, and talc.

[0007] Specifically, component A comprises, by mass, 4-8 parts potassium indolebutyrate, 200-400 parts soluble starch, 5-15 parts crotonin, 100-150 parts salicylic acid, and 200-500 parts talc.

[0008] Specifically, component B comprises, by mass, 4-8 parts indolebutyric acid, 200-400 parts sucrose, 5-15 parts chlorogenic acid, 100-150 parts vitamin C, and 200-500 parts talc. Specifically, the mass ratio of component A to component B is (1-4):(4-1).

[0009] Preferably, the mass ratio of component A to component B is 1:1.

[0010] This invention also discloses a method for promoting rooting of tender shoots of Eucommia ulmoides. The method includes the steps of scion nursery management, cutting bed preparation, scion preparation and treatment, cutting and post-cutting management. Before cutting, the scions are treated with the rooting agent.

[0011] The seedling cultivation method includes the following specific steps:

[0012] S1 Scion Nursery Management: Select young *Cyclocarya paliurus* seedlings as scion mother plants and cut them back. After cutting back the trunks, loosen the soil, remove weeds, and apply urea.

[0013] S2 Cutting Bed Preparation: Set up the cutting bed and spread the cutting substrate evenly on the bed, then cover and seal it with film for sterilization;

[0014] S3 Cutting Preparation and Treatment: Semi-lignified branches are cut from the mother plant as cuttings, and the cuttings are prepared and disinfected.

[0015] S4 Cuttings: After treating the cuttings with the aforementioned rooting agent, they are inserted into the soil and a greenhouse is built.

[0016] S5 Post-planting Management: Control the temperature, relative humidity, and light intensity inside the greenhouse, and regularly carry out sterilization, and remove dead branches and fallen leaves.

[0017] Specifically, the stem cutting height in step S1 is 5 to 10 cm above the ground diameter.

[0018] Specifically, the method for preparing the cutting substrate in step S2 is as follows: peat moss, perlite, and river sand are mixed in a volume ratio of 2-3:1:1 to prepare the cutting substrate; when mixing the substrate, 50g each of 50% carbendazim wettable powder and 75% chlorothalonil wettable powder are added per cubic meter of substrate.

[0019] Specifically, the fungicide used in the cutting disinfection operation in step S3 is a 2000-3000 times dilution of 30% hymexazol aqueous solution and a 1000-2000 times dilution of 50% carbendazim wettable powder.

[0020] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0021] 1. The rooting time of *Cyclocarya paliurus* cuttings treated with the root-promoting agent disclosed in this invention is significantly shortened. Besides the root-promoting effects of potassium indolebutyrate and indolebutyric acid in the root-promoting agent, the low concentration of cymoxanil in excipients A and B can promote cell differentiation and accelerate callus formation; secondly, the soluble starch and sucrose in the excipients provide carbon sources, accelerating callus and root formation; and vitamin C in the excipients has a significant antioxidant effect, inhibiting the oxidation of phenolic acids in *Cyclocarya paliurus* cuttings to quinones. The synergistic effect of these components accelerates the rooting process, thereby shortening the time required for rooting.

[0022] 2. Cuttings of *Cyclocarya paliurus* treated with the rooting agent disclosed in this invention exhibit high rooting rate, a large number of adventitious roots and lateral roots, and high root quality. Indolebutyric acid in component B of the rooting agent induces the formation of root primordia in the cuttings, promotes cell differentiation and division, which is beneficial for new root formation and vascular system differentiation, thus promoting the formation of adventitious roots. Potassium indolebutyrate in component A promotes the growth of fine, sparse, and highly branched lateral roots and fibrous roots. Through the combined use and synergistic effect of components A and B, this invention effectively promotes the longitudinal distribution of adventitious roots on the cuttings, increasing the number of roots; component B effectively promotes the horizontal expansion of adventitious roots, forming more secondary lateral roots, thereby achieving the technical effect of high rooting rate, a large number of adventitious roots and lateral roots, and high root quality in *Cyclocarya paliurus* cuttings.

[0023] 3. High survival rate of transplanted cuttings. The cuttings treated with this root-promoting agent develop well-developed functional root systems with numerous lateral roots. Anatomically, the root tissue connects seamlessly with the cuttings to form a complete vascular system, ensuring water balance during transplantation. The integrity and quantity of the root system guarantee a high survival rate after transplanting.

[0024] 4. The seedling cultivation process is simple and the raw materials are readily available, facilitating large-scale promotion. The method for propagating *Cyclocarya paliurus* using softwood cuttings in this invention utilizes readily available cutting substrate materials, which are simple and convenient to prepare, and the propagation method is easy to implement. The cuttings are shorter than those from conventional softwood cuttings, reducing the interval between cutting collection and increasing the propagation coefficient. *Cyclocarya paliurus* softwood cuttings result in shorter rooting time, a greater number of roots, higher root quality, stable rooting rate, and high transplant survival rate, making them suitable for widespread application in the *Cyclocarya paliurus* industry.

[0025] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0026] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0027] Figure 1 Photograph of *Cyclocarya paliurus* seedlings cultivated in Example 1;

[0028] Figure 2 Photograph of Cyclocarya paliurus seedlings (60 days) cultivated for Comparative Example 1;

[0029] Figure 3 Photograph of Cyclocarya paliurus seedlings (60 days) cultivated for Comparative Example 2;

[0030] Figure 4 Photograph of Cyclocarya paliurus seedlings (60 days) cultivated for Comparative Example 3. Detailed Implementation

[0031] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0032] This invention discloses a rooting agent for promoting rooting of tender cuttings of Eucommia ulmoides. The rooting agent is composed of two components, component A and component B. Component A consists of potassium indolebutyrate, soluble starch, crotonin, salicylic acid, and talc. Component B consists of indolebutyric acid, sucrose, crotonin, vitamin C, and talc.

[0033] Component A and Component B contain potassium indolebutyrate and indolebutyric acid, respectively. These two components have different chemical properties. Potassium indolebutyrate is an inorganic salt, completely soluble in water, and due to the hygroscopic nature of the talc powder in the ingredients, it is prone to absorbing moisture during storage. Indolebutyric acid, on the other hand, has extremely low solubility in water. Therefore, they must be prepared separately and stored away from light, and then mixed before use to help maintain the activity of both potassium indolebutyrate and indolebutyric acid.

[0034] Potassium indolebutyrate: a plant growth regulator that is readily soluble in water, stable, and easily translocated within the body. It promotes cell division and proliferation, and induces the formation of adventitious roots. Its main function is to promote the growth of fine, sparse, and multi-branched lateral roots and fibrous roots in cuttings, effectively preventing the formation of fleshy roots.

[0035] Soluble starch: an easily absorbed carbon source. During rooting, it provides nutrients for callus formation, root primordia differentiation, elongation growth, and lateral root formation.

[0036] Crown-like chlorophyll: A novel plant growth regulator. It can promote the increase of anthocyanins, induce the production of chlorophyllase, and has a wide range of physiological functions, including regulating growth, inhibiting senescence, promoting cell differentiation, increasing chlorophyll content, and enhancing plant stress resistance.

[0037] Salicylic acid: a novel plant hormone with physiological regulatory functions. It plays a role in regulating growth, inhibiting senescence, and acting as an antioxidant. It not only directly participates in plant growth and development, but can also regulate plant growth and development by affecting the levels of other endogenous plant hormones.

[0038] Talc: A high-quality filler containing a large amount of silicon. It is non-toxic, odorless, and has a high whiteness, effectively protecting the cut ends of cuttings.

[0039] Indolebutyric acid (IBA): A plant growth regulator that is not easily transported within the plant after being absorbed by the cutting. It often remains at the base of the cutting and can induce cambium cell differentiation and division, producing callus tissue, which is beneficial for the formation of new roots and the differentiation of the vascular bundle system, and promotes the formation of adventitious roots in the cutting.

[0040] Sucrose: an important carbon source. In root formation and growth, it not only provides nutrition as a carbohydrate, but also has hormone-like effects, inducing root formation and promoting root growth.

[0041] Vitamin C: Can be used as a nutritional supplement and antioxidant. It can enhance the plant's resistance, and has the effects of disinfection, sterilization, inhibiting the reproduction of harmful microorganisms, and promoting root growth.

[0042] Synergistic effect: Under the action of plant growth regulators indolebutyric acid (IBA) and potassium indolebutyrate (IDP), tender cuttings of *Eucommia ulmoides* induce cell differentiation and proliferation in the cambium layer, gradually producing callus tissue. Simultaneously, under the action of related enzymes, and with the carbon source provided by photosynthetic products from leaves and sucrose and soluble starch in the rooting agent, root primordia are induced from the callus tissue to form new roots. The vascular system also further differentiates, connecting the new roots with the vascular system of the cuttings. Furthermore, the synergistic effect of talc, chlorothalonil, vitamin C, and salicylic acid in the formulation enhances the stress resistance of the cuttings, disinfects and sterilizes, inhibits the growth of harmful microorganisms, prevents oxidative aging of the cuttings, accelerates the rooting process, and increases the rooting rate.

[0043] Specifically, component A comprises, by mass, 4-8 parts potassium indolebutyrate, 200-400 parts soluble starch, 5-15 parts chlorhexidine, 100-150 parts salicylic acid, and 200-500 parts talc. For example, potassium indolebutyrate is 4, 5, 6, 7, or 8 parts; soluble starch is 200, 230, 270, 310, 340, or 390 parts; chlorhexidine is 5, 7, 11, or 14 parts; salicylic acid is 100, 110, 125, 135, or 147 parts; and talc is 200, 270, 330, 380, 440, or 490 parts.

[0044] In particular, too low a content of potassium indolebutyrate will result in no rooting or few roots; too high a content will cause leaf withering or even shedding, inhibiting growth and rooting. Excessive use of soluble starch will cover the cut end, affecting water absorption and causing water imbalance within the cutting, thus reducing the rooting rate. As a growth regulator, excessively high concentrations of styraxin inhibit root growth and suppress defense mechanisms relying on stomata and salicylic acid. Excessive use of salicylic acid will inhibit plant growth and has toxic effects. Talc can effectively protect the cutting cut end; too low a concentration will not completely cover the lower cut end; too high a concentration will hinder water absorption by the lower cut end, affecting rooting.

[0045] For example, component A may be 4 parts potassium indolebutyrate, 300 parts soluble starch, 10 parts crotonin, 150 parts salicylic acid, and 400 parts talc; or 6 parts potassium indolebutyrate, 200 parts soluble starch, 15 parts crotonin, 120 parts salicylic acid, and 280 parts talc; or 8 parts potassium indolebutyrate, 380 parts soluble starch, 13 parts crotonin, 110 parts salicylic acid, and 220 parts talc.

[0046] Specifically, component B comprises, by mass, 4-8 parts indolebutyric acid, 200-400 parts sucrose, 5-15 parts crotonin, and 100-150 parts vitamin C; for example, indolebutyric acid is 4, 5, 6, 7, or 8 parts; sucrose is 200, 230, 270, 310, 340, or 390 parts; crotonin is 5, 7, 11, or 14 parts; and vitamin C is 100, 117, 128, 134, or 146 parts.

[0047] Indolebutyric acid (IBA) is problematic in several ways. Too little IBA results in poor root development or few roots; too much IBA leads to few roots, root deformities, or fleshy roots. Excessive supplementation of sucrose, chlorophyll, and vitamin C is not beneficial but rather harmful to plants. Talc effectively protects the cut end of cuttings; too little talcum powder fails to completely cover the cut, while too much prevents the cut end from absorbing water, hindering root development.

[0048] For example, component B may be 4 parts indolebutyric acid, 300 parts sucrose, 13 parts crotonin, 150 parts vitamin C, and 370 parts talc; or 7 parts indolebutyric acid, 380 parts sucrose, 10 parts crotonin, 110 parts vitamin C, and 210 parts talc.

[0049] Specifically, the mass ratio of component A to component B is (1-4):(4-1), for example, a mass ratio of 1:3, 2:3, 1:1, 3:2, or 4:1. Component A can promote the formation of more adventitious roots in cuttings. According to previous experimental results, the rooting agent component A can effectively promote the longitudinal distribution of adventitious roots on the cuttings, increasing the number of roots; component B can effectively promote the horizontal expansion of adventitious roots, forming more secondary lateral roots. According to the experimental results, the mass ratio of component A to component B (1-4):(4-1) can effectively improve the rooting rate and rooting quality of cuttings; among them, when the mass ratio of component A to component B is 1:1, the rooting rate is the highest, the root quality is the best, and the transplant survival rate is also the highest.

[0050] Preferably, the mass ratio of component A to component B is 1:1.

[0051] Specifically, the root-promoting agent is in powder form. Powder formulations are more effective in maintaining their efficacy during preparation, storage, and widespread use. During preparation, the two components of the powder can be mixed thoroughly according to a specific ratio before use. Indolebutyric acid, potassium indolebutyrate, salicylic acid, and vitamin C solutions are suitable for low-temperature storage and are prone to decomposition and oxidation under high-temperature conditions. Therefore, powder formulations are more convenient in terms of storage, transportation, and widespread use.

[0052] This invention also discloses a method for promoting rooting of tender shoots of Eucommia ulmoides. The method includes the steps of scion nursery management, cutting bed preparation, scion preparation and treatment, cutting and post-cutting management. Before cutting, the scions are treated with the rooting agent.

[0053] The seedling cultivation method includes the following specific steps:

[0054] S1 Scion Nursery Management: Select young *Cyclocarya paliurus* seedlings as scion mother plants and cut them back. After cutting back the trunks, loosen the soil, remove weeds, and apply urea.

[0055] S2 Cutting Bed Preparation: Set up the cutting bed and spread the cutting substrate evenly on the bed, then cover and seal it with film for sterilization;

[0056] S3 Cutting Preparation and Treatment: Semi-lignified branches are cut from the mother plant as cuttings, and the cuttings are prepared and disinfected.

[0057] S4 Cuttings: After treating the cuttings with the aforementioned rooting agent, they are inserted into the soil and a greenhouse is built.

[0058] S5 Post-planting Management: Control the temperature, relative humidity, and light intensity inside the greenhouse, and regularly carry out sterilization, and remove dead branches and fallen leaves.

[0059] Specifically, step S1 involves selecting robust, disease-free 1-2 year old seedlings of superior Cyclocarya paliurus seed sources or families as mother plants for cuttings; from late February to early March, the mother plants are pruned, the soil is loosened and weeds are removed, and 3-5 g of urea is applied per plant. The younger the mother plant, the stronger its rooting ability; after pruning, more robust scions can be produced from the root collar, thus improving the quantity and quality of cuttings.

[0060] Specifically, the stem cutting height described in step S1 is 5-10 cm above the ground diameter. Lowering the cutting height reduces the height at which adventitious buds sprout, bringing them closer to the root collar; the closer to the root collar, the younger the physiological age, which is more conducive to rooting; too low a cutting height will reduce the number of sprouts, failing to meet the needs of large-scale production.

[0061] Specifically, step S2 involves setting up the propagation bed in a colorless, transparent glass greenhouse. The bed surface is 1.0–1.5 m wide, and a 10–15 cm high baffle is installed around it to ensure the thickness of the bed and facilitate manual operation. A black ground cover with a weight of 100–120 g / m² is laid on the bed surface. 2 The permeability is 3.5 L / (s·m). 2 This is to maintain a stable moisture content in the cutting substrate.

[0062] Specifically, the preparation method of the cutting substrate in step S2 is as follows: peat moss, perlite, and river sand are mixed in a volume ratio of 2-3:1:1 to prepare the cutting substrate. The substrate composition includes organic and inorganic substrates, and the ratio ensures the substrate's permeability, aeration, and water retention. When mixing the substrate, 50g each of 50% carbendazim wettable powder and 75% chlorothalonil wettable powder are added per cubic meter of substrate for disinfection. The substrate thickness is 10-13cm, which matches the length of the cuttings. The substrate moisture content is 60-80% of field capacity, which is the suitable moisture content for plant growth, ensuring both water and aeration.

[0063] Specifically, step S3 involves taking healthy, disease-free, semi-lignified branches from the current year's growth, free from pests and diseases, from the mother plant between May and early August (the suitable sampling time for softwood cuttings). The branches are then prepared into cuttings of the same size, with the top cut flat and the bottom cut obliquely cut to increase the water absorption area of ​​the lower cut and reduce the water loss area of ​​the upper cut, maintaining the plant's internal water balance. Each cutting retains 1-2 buds and preserves 1-2 healthy leaflets at the base of the compound leaf. The cuttings are disinfected with a fungicide by soaking for 2 minutes, then air-drying for 2-3 minutes before immediate planting. This step significantly reduces the risk of infection for the cuttings.

[0064] Specifically, the cuttings should be 8–13 cm long and 0.3–0.5 cm thick, with the upper cut 1–2 cm from the upper bud. This cutting specification ensures a high survival rate (biological activity) while minimizing material usage and maximizing the number of cuttings.

[0065] Specifically, the fungicides used in step S3 for disinfecting the cuttings are a 2000-3000 times dilution of 30% hymexazol aqueous solution and a 1000-2000 times dilution of 50% carbendazim wettable powder. Hymexazol is a systemic, highly effective fungicide, soil disinfectant, and also a plant growth regulator. It has unique efficacy, being highly effective, low in toxicity, and pollution-free, making it a green, environmentally friendly, high-tech product. It can effectively inhibit the normal growth of pathogenic fungal mycelium or directly kill pathogens, while also promoting plant growth; it also promotes root growth and development, resulting in strong seedlings and improved crop survival rates. Hymexazol has extremely high penetration, with an efficacy lasting up to two weeks. Carbendazim is a broad-spectrum fungicide, effective against fungal diseases in various crops. The concentrations of the fungicides determined in this invention, based on the instructions for use and specific experimental results of the two fungicides, are within a range that achieves the desired disinfection effect.

[0066] Specifically, step S4 involves using the powder-dipping method on the lower cut of the cutting, thoroughly coating it with rooting agent, and immediately inserting it into the soil. Cuttings are placed in the propagation bed at a spacing of 5cm x 10cm, with a depth of 2-3cm. The substrate around the cuttings is then compacted to ensure close contact between the cuttings and the substrate. Immediately after insertion, a fungicide is sprayed, and the leaves are rinsed. A small arched structure, 60-70cm high, is erected over the bed and covered with 4C plastic film, sealing the edges to maintain substrate and air humidity. The spacing is determined based on the size of the young *Eucommia ulmoides* cuttings, ensuring that adjacent cuttings do not obstruct or touch each other. The 2-3cm insertion depth is determined based on the rooting location of adventitious roots, which is generally about 2cm above the lower cut.

[0067] Specifically, step S5 involves paying close attention to the temperature and humidity of the environment and substrate daily after cutting. The air temperature inside the greenhouse should be maintained between 20 and 32°C, the relative humidity between 85% and 90%, and the indoor light intensity between 30,000 and 50,000 lux. A fungicide should be sprayed every 10 to 14 days after cutting, and withered, moldy plants and fallen leaves should be removed promptly. Maintaining an air temperature of 20 to 32°C inside the greenhouse is beneficial for callus formation in the cuttings; controlling the relative humidity at 85% to 90% and the indoor light intensity at 30,000 to 50,000 lux is beneficial for leaf photosynthesis while maintaining water balance; removing withered, moldy plants and fallen leaves provides a good sanitary environment for the remaining cuttings and avoids cross-infection.

[0068] In practice, after cutting, a temperature and humidity monitoring system can be used to monitor the air and the temperature and humidity of the cutting substrate inside the greenhouse. The indoor temperature can be controlled by the greenhouse shading system and water curtain. When the weather is too hot, appropriate spraying can be used to cool down and supplement the air humidity.

[0069] Specifically, the fungicides used for sterilization in step S5 are 2000-3000 times dilution of 30% hymexazol aqueous solution and 1000-2000 times dilution of 50% carbendazim wettable powder.

[0070] Example group (including comparative examples):

[0071] In mid-May 2021, healthy, disease-free, semi-lignified branches of the current year were taken from the mother plant as cuttings. The branches were prepared into cuttings of the same size, with a flat top cut and a slanted bottom cut. Each cutting retained 1-2 buds and preserved 1-2 healthy leaflets at the base of the compound leaf. The cuttings were 8-13 cm long and 0.3-0.5 cm thick, with the top cut 1-2 cm from the top bud. The cuttings were disinfected and sterilized with a 2000-3000 times dilution of 30% carbendazim aqueous solution and a 1000-2000 times dilution of 50% carbendazim wettable powder. After soaking for 2 minutes, they were removed, air-dried for 2-3 minutes, and immediately planted.

[0072] Three base materials for rooting agents were selected: ABT-1 (commercially available ABT rooting powder No. 1), component A (each portion containing: 4 mg potassium indolebutyrate, 400 mg soluble starch, 15 mg cymoxanil, 150 mg salicylic acid, 431 mg talc), and component B (each portion containing: 8 mg indolebutyric acid, 400 mg sucrose, 15 mg cymoxanil, 150 mg vitamin C, 442 mg talc). Six rooting agent formulations were prepared according to the specified mass ratios (Table 1) to study their effects on the rooting of *Cyclocarya paliurus* cuttings and to screen the optimal rooting agent combination for *Cyclocarya paliurus* cuttings.

[0073] Starting from the 10th day after cutting, the rooting morphology was observed, and the rooting rate, number of adventitious roots, and root length of the cuttings were counted after 60 days. The rooting quality index was calculated.

[0074] The rooting quality index is calculated as follows: Average number of adventitious roots = Σn i / N; Average root length = Σ[Σ(n Lx L x )] i / Σn i Average total root length = Rooting rate × Average number of adventitious roots × Average root length.

[0075] In the formula, N represents the rooted cutting, n represents the indefinite number of roots, i represents the cutting number in each repeated rooted cutting, and L... x Let n be the length of the indeterminate root. LxThe number of adventitious roots classified according to different root lengths.

[0076] Table 1. Formula for rooting agent for *Cyclocarya paliurus* tender branch cuttings

[0077]

[0078]

[0079] Example 1: Treatment of cuttings ( Figure 1 At 10 days, the cut swells and callus tissue appears; at 15 days, bud-like adventitious roots appear in the callus tissue; at 20-30 days, a large number of roots grow, mainly effective roots; at around 30 days, lateral roots begin to appear; at 40-60 days, the root system is well developed and a large number of lateral roots are produced.

[0080] At the end of 60 days after cutting propagation, the data in Table 2 showed that, except for Comparative Examples 1-3, the average rooting rate of all examples reached a high level. Among them, Example 1 showed the most significant rooting rate, reaching 93.06%. The cuttings treated in Example 1 had the highest average number of adventitious roots, reaching 6.83, demonstrating excellent rooting ability. Simultaneously, the average root length reached 9.38 cm, and the average total root length was the highest, reaching 59.55 cm. This indicates that the cuttings treated in Example 1 had excellent rooting quality and strong rooting ability and growth potential. Furthermore, the transplant survival rate of the Example 1 treatment was the highest, reaching 90.37%.

[0081] Table 2. Multiple comparisons of rooting rate and quality indicators of *Cyclocarya paliurus* cuttings with different formulations at 60 days.

[0082]

[0083]

[0084] In summary, the cuttings treated in Example 1 (B series: A series = 1:1) have a short rooting time, a large number of roots, a high rooting rate, well-developed root system with many lateral roots, high root quality, and a high transplant survival rate, making it the optimal formula.

[0085] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A rooting agent for promoting rooting of *Cyclocarya paliurus* cuttings, characterized in that: The root-promoting agent consists of two components, component A and component B. Component A consists of potassium indolebutyrate, soluble starch, crotonin, salicylic acid, and talc; component B consists of indolebutyric acid, sucrose, crotonin, vitamin C, and talc. The components of component A, by mass, are 4-8 parts potassium indolebutyrate, 200-400 parts soluble starch, 5-15 parts crotonin, 100-150 parts salicylic acid, and 200-500 parts talc. The components of component B, by mass, are 4-8 parts indolebutyric acid, 200-400 parts sucrose, 5-15 parts crotonin, 100-150 parts vitamin C, and 200-500 parts talc. The mass ratio of component A to component B is (1-4):(4-1).

2. The root enhancer according to claim 1, characterized in that: The mass ratio of component A to component B is 1:

1.

3. A seedling raising method for promoting rooting of Adenanthera pavonina young branch cutting, characterized by: The seedling cultivation method includes the steps of scion nursery management, cutting bed preparation, scion preparation and treatment, cutting and post-cutting management, wherein the scions are treated with the root-promoting agent described in any one of claims 1 to 2 before cutting.

4. The seedling raising method according to claim 3, characterized by, The specific steps include the following: S1 Scion Nursery Management: Select young *Cyclocarya paliurus* seedlings as scion mother plants and cut them back. After cutting back the trunks, loosen the soil, remove weeds, and apply urea. S2 Cutting bed preparation: Set up the cutting bed and spread the cutting substrate evenly on the seedbed, then cover and seal it with film for sterilization; S3 Cutting preparation and treatment: Semi-lignified branches are cut from the mother plant as cuttings, and the cuttings are prepared and disinfected. S4 Cuttings: Cuttings are treated with the rooting agent described in any one of claims 1 to 2 and then inserted into a greenhouse. S5 Post-planting management: Control the temperature, relative humidity, and light intensity inside the greenhouse, and regularly carry out sterilization, and remove dead branches and fallen leaves.

5. The method of raising seedlings according to claim 4, characterized in that: The stem cutting height mentioned in step S1 is 5 to 10 cm above the ground diameter.

6. The seedling raising method according to claim 4, characterized in that: The method for preparing the cutting substrate in step S2 is as follows: mix peat moss, perlite, and river sand in a volume ratio of 2-3:1:1 to prepare the cutting substrate; when mixing the substrate, add 50g each of 50% carbendazim wettable powder and 75% chlorothalonil wettable powder per cubic meter of substrate.

7. The method of raising seedlings according to claim 4, characterized in that: The fungicides used in the cutting disinfection operation in step S3 are 2000-3000 times dilution of 30% hymexazol aqueous solution and 1000-2000 times dilution of 50% carbendazim wettable powder.

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