Preparation for promoting root development of plants in desert region and application of preparation

Abstract

The invention relates to the technical field of desert ecological restoration, in particular to a preparation for promoting root development of plants in a desert region and application of the preparation. The invention provides a composition for promoting development of a plant root system in a desert region. The composition comprises a complex microbial inoculant, a hippophae rhamnoides fruit extract, potassium fulvate, attapulgite, humic acid, potassium nitrate, boric acid and deionized water, the complex microbial inoculants comprise Saccharobacter deserticola and Sonora deserticola. The composition and the preparation for promoting the development of the root systems of the plants in the desert region are high in pertinence, remarkable in root promoting effect and long in lasting period, the stress resistance of the plants can be improved, and the problem that the survival rate of the plants planted in the desert region is low can be effectively solved.

Description

Technical Field

[0002] This invention relates to the field of desert ecological restoration technology, and in particular to a preparation for promoting the root development of plants in desert areas and its application. Background Technology

[0004] Desert regions are characterized by arid climates, scarce rainfall, and infertile soil with poor water and fertilizer retention capacity, making them among the most ecologically fragile areas globally. Vegetation restoration is a core measure for ecological restoration in desert regions. However, due to the unique habitat conditions in desert areas, planted plants generally suffer from slow root development, shallow rooting, few lateral roots, and weak resistance to adverse conditions, resulting in low survival rates and slow growth. This severely restricts the efficiency and quality of vegetation establishment in desert regions.

[0005] To address the aforementioned issues, existing technologies have developed some plant growth regulators, such as synthetic rooting agents like naphthaleneacetic acid (NAA) and indolebutyric acid (IBA). While these can promote root germination to some extent, they suffer from the following drawbacks: First, they lack specificity, failing to consider the arid and barren habitat conditions of desert regions, making it difficult to simultaneously meet the needs of root development and enhanced stress resistance. Second, their effects are short-lived, easily washed away by rainwater or decomposed by soil microorganisms, requiring multiple applications and increasing costs. Third, improper dosage of some synthetic regulators can be toxic to plants and may pose potential risks to the soil ecosystem. Furthermore, existing technologies have also attempted to use microbial inoculants to promote plant growth, but most employ non-native microbial strains, which exhibit poor adaptability and weak survival ability in the extreme environments of desert regions, making it difficult to achieve stable growth-promoting effects.

[0006] Therefore, developing a formulation that can adapt to the special habitat conditions of desert areas, has both root-promoting and stress-enhancing effects, a long-lasting effect, and is environmentally friendly, along with its supporting application methods, is of great practical significance for improving the efficiency of vegetation restoration in desert areas and promoting ecological restoration in desert areas. Summary of the Invention

[0008] The purpose of this invention is to provide a formulation for promoting root development of plants in desert areas and its application, thereby solving the problems existing in the prior art. The composition and formulation for promoting root development of plants in desert areas provided by this invention are highly targeted, have significant root-promoting effects, long-lasting effects, and can enhance plant stress resistance, effectively solving the problem of low survival rate of plant planting in desert areas.

[0009] To achieve the above objectives, the present invention provides the following solution:

[0010] This invention provides a composition for promoting root development of plants in desert areas, comprising the following components in parts by weight: 15-25 parts of compound microbial agent, 5-10 parts of sea buckthorn extract, 8-12 parts of potassium humate, 20-30 parts of attapulgite, 10-15 parts of humic acid, 3-5 parts of potassium nitrate, 1-2 parts of boric acid, and 50-100 parts of deionized water.

[0011] The compound microbial agent includes Bacillus desertis and Bacillus sonora.

[0012] The components in the composition provided by this invention have a synergistic effect, achieving an integrated function of "root promotion + environmental modification + stress resistance":

[0013] 1. Compound microbial agents: *Bacillus desertica* and *Bacillus sonora* exhibit strong adaptability to the arid, high-temperature, and infertile environments of desert regions, enabling them to stably colonize around plant roots. These two bacteria secrete plant growth regulators such as auxins, indoleacetic acid, and gibberellins, directly promoting root cell division and elongation. They also secrete phosphatases and ureases, converting insoluble phosphorus and nitrogen in the soil into forms that plants can absorb and utilize, improving soil fertility and providing nutritional support for root development. Simultaneously, reduced disease means reduced root damage, indirectly maintaining continuous root growth.

[0014] 2. Sea buckthorn extract: Sea buckthorn extract is rich in flavonoids, which can activate the expression of root-related genes in plant roots, promote the germination of adventitious roots and lateral roots, and also have antioxidant effects. They can eliminate reactive oxygen species produced by plant roots under drought stress, reduce drought damage to roots, and enhance the root system's resistance to stress.

[0015] 3. Potassium fulvate and humic acid: Potassium fulvate has good water solubility and complexing ability, which can complex trace elements in the soil, improve nutrient utilization, and promote the permeability of plant root cell membranes, thereby enhancing the roots' ability to absorb water and nutrients; humic acid can improve soil structure, increase the content of soil aggregates, and enhance the soil's water and fertilizer retention capacity, creating a good soil environment for root development.

[0016] 4. Attapulgite: Attapulgite itself has a large specific surface area and strong adsorption capacity, which can adsorb and slowly release nutrients and microbial metabolites in the formulation, prolonging the effect of the formulation; at the same time, attapulgite can also adsorb salt in the soil, reduce the degree of soil salinization, and improve the soil microenvironment for root growth.

[0017] 5. Potassium nitrate and boric acid: Potassium nitrate provides nitrogen and potassium to plants. Nitrogen is an important raw material for plant protein synthesis and promotes root cell growth. Potassium can enhance the toughness of plant cell walls and improve the root system's resistance to lodging and drought. Boric acid participates in the reproductive growth and cell wall synthesis of plants and can promote root elongation and lateral root differentiation.

[0018] Preferably, the effective viable count of *Bacillus desertica* and *Bacillus sonora* in the compound bacterial agent is 10. 8 10 7 .

[0019] Preferably, the method for preparing the sea buckthorn extract includes the step of mixing sea buckthorn and water and then performing water extraction.

[0020] This invention provides the use of the above-described composition in the preparation of formulations that promote root development of plants in desert areas.

[0021] The present invention provides an agent for promoting root development of plants in desert areas, comprising the above-described composition.

[0022] This invention provides a method for preparing the above-described agent for promoting root development in desert plants, comprising the following steps:

[0023] S1. The *Bacillus desertis* and *Bacillus sonora* were fermented and cultured separately, then mixed to obtain the composite bacterial agent;

[0024] S2. Mix the attapulgite, potassium humate, and humic acid to obtain a composite carrier;

[0025] S3. The sea buckthorn extract, potassium nitrate, boric acid, and deionized water are mixed to obtain an aqueous phase component;

[0026] S4. Mix the compound microbial agent, the compound carrier, and the aqueous phase component to obtain the preparation for promoting root development of plants in desert areas.

[0027] The present invention provides the application of the composition as described above or the preparation for promoting root development of plants in desert areas in promoting root development of plants in desert areas.

[0028] Preferably, the plant includes one or more of sea buckthorn, alfalfa, caragana, Mongolian euphorbia, and saxaul.

[0029] The present invention provides a method for promoting root development of plants in desert areas, comprising the step of applying the above-mentioned preparation for promoting root development of plants in desert areas to the plants.

[0030] Preferably, the application method includes one or more of seed coating, root irrigation, and hole application;

[0031] The plants include one or more of the following: sea buckthorn, sand fern, caragana, Mongolian euphorbia, and saxaul.

[0032] The present invention discloses the following technical effects:

[0033] 1. Significant root-promoting effect: The composition and preparation provided by this invention use a compound of bacteria (Bacillus desertis and Bacillus sonora) and plant-derived sea buckthorn extract to synergistically promote the germination of plant roots. Experimental verification shows that after applying this composition and preparation, the rooting rate and survival rate of desert plants such as sea buckthorn and Haloxylon ammodendron are significantly improved.

[0034] 2. Strong stress resistance: The composite carrier (attapulgite, potassium humate, humic acid) in the composition and preparation provided by this invention can improve soil structure, enhance soil water and fertilizer retention capacity, and at the same time enhance the drought resistance and barrenness tolerance of plant roots, enabling plants to grow stably in the extreme environment of desert areas and significantly improve the survival rate.

[0035] 3. Long duration of effect: Attapulgite has good slow-release properties, which can adsorb and slowly release the active ingredients in the formulation, extending the duration of effect to 3-6 months, reducing the number of applications and lowering the application cost.

[0036] 4. Environmentally friendly: The compositions and preparations provided by this invention use natural plant extracts and compound bacteria (Bacillus desertis and Bacillus sonora), with no chemical synthetic regulator residues, and will not damage the soil ecological environment; at the same time, the humic acid, potassium fulvate and other components in the preparations can also improve soil fertility and promote the restoration of the soil ecosystem.

[0037] 5. Flexible application: The supporting application methods include three methods: seed coating, seedling root irrigation, and hole application, which are suitable for different site conditions, plant species and planting stages in different desert areas. It is highly practical and easy to promote. Detailed Implementation

[0039] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0040] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0041] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0042] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This specification and embodiments are merely exemplary.

[0043] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0044] CN105684767A discloses a filler material for stabilizing plant roots in desertified areas and its application method. This filler material is a hollow cylindrical structure with an open top and closed bottom, formed by biodegradable inner and outer wall structures and planting holes for planting plants. The hollow structure between the inner and outer walls and the planting holes are filled with the same filler material. The filler material is a mixture of sand, humus, straw, local soil, humus, and microbial agents in a volume ratio of 1:2:1:3:2:1. The humus in the filler material has a moisture content of not less than 20%. The straw is not longer than 5 cm. The microbial agents consist of Nocardia actinomycetes, Bacillus subtilis, Bacillus megaterium, photosynthetic bacteria, filamentous bacteria, and alcohol yeast, and the effective viable bacteria count of the microbial agents is not less than 19 billion / g.

[0045] CN102172191A, "A Rapid Method for Improving the Survival Rate of Artificially Restored Populus euphratica in Arid Desert Areas," discloses a rapid method for improving the survival rate of artificially restored Populus euphratica in arid desert areas. The method is characterized by the following steps: a) Planting Populus euphratica seedlings on uncovered, shifting sand with a spacing of 5-10 meters between seedlings, using healthy 1-2 year old seedlings; b) Using a soil drill, drilling 4 holes in the east and west directions at approximately 30-40cm and 80-120cm from the root edge of the Populus euphratica roots. c) After confirming the artificial restoration of poplar seedlings and planting, water is injected into the poplar root irrigation devices. In the first growing year, water is injected 2-3 times into the poplar root irrigation devices fixed in the pits 30-40cm deep at the edge of the poplar roots. In the second growing year, water is injected 2-3 times into the poplar root irrigation devices fixed in the pits 80-120cm deep at the edge of the poplar roots, so that the poplar roots can develop horizontally.

[0046] CN104871789A, "A Method for Increasing Organic Carbon Sequestration by Halophytic Herbs in Arid Desert Areas," discloses a method for increasing organic carbon sequestration by halophytic herbaceous plants in arid desert areas. The method is characterized by the following steps: In areas where halophytic herbaceous plants such as *Chrysanthemum indicum*, *Chrysanthemum indicum*, *Aquilaria sinensis*, or *Alpinia zerumbet* grow: a) In late spring, when the surface temperature is maintained at 20°C, or when the herbaceous plants *Chrysanthemum indicum*, *Chrysanthemum indicum*, *Aquilaria sinensis*, or *Alpinia zerumbet* grow to 210 cm, dig trenches or drill holes. The trenches are dug every 5 m, with a width of 0.5-1 m and a depth of... a) Drill holes 3-10cm deep using a Luoyang shovel, making 5-25 holes every 5m, each 8mm in size and 5-12cm deep; b) During the growing season, dig strips or drill holes 2-3 times. In the dug strips, apply nitrate nitrogen at a nitrogen level of 10-15mmol / L for 1-5cm, water, and then carry out subsequent management as usual; or in the drilled holes, apply nitrate nitrogen at a nitrogen level of 10-15mmol / L for 1-5cm, water, and then carry out subsequent management as usual.

[0047] The aforementioned methods still suffer from drawbacks such as complexity and high labor costs, and cannot fundamentally address the problem of promoting plant root development in desert areas.

[0048] The components in the composition provided by this invention have a synergistic effect, achieving an integrated function of "root promotion + environmental modification + stress resistance":

[0049] 1. Compound microbial agents: *Bacillus desertica* and *Bacillus sonora* exhibit strong adaptability to the arid, high-temperature, and infertile environments of desert regions, enabling them to stably colonize around plant roots. These two bacteria secrete plant growth regulators such as auxins, indoleacetic acid, and gibberellins, directly promoting root cell division and elongation. They also secrete phosphatases and ureases, converting insoluble phosphorus and nitrogen in the soil into forms that plants can absorb and utilize, improving soil fertility and providing nutritional support for root development. Simultaneously, reduced disease means reduced root damage, indirectly maintaining continuous root growth.

[0050] 2. Sea buckthorn extract: Sea buckthorn extract is rich in flavonoids, which can activate the expression of root-related genes in plant roots, promote the germination of adventitious roots and lateral roots, and also have antioxidant effects. They can eliminate reactive oxygen species produced by plant roots under drought stress, reduce drought damage to roots, and enhance the root system's resistance to stress.

[0051] 3. Potassium fulvate and humic acid: Potassium fulvate has good water solubility and complexing ability, which can complex trace elements in the soil, improve nutrient utilization, and promote the permeability of plant root cell membranes, thereby enhancing the roots' ability to absorb water and nutrients; humic acid can improve soil structure, increase the content of soil aggregates, and enhance the soil's water and fertilizer retention capacity, creating a good soil environment for root development.

[0052] 4. Attapulgite: Attapulgite itself has a large specific surface area and strong adsorption capacity, which can adsorb and slowly release nutrients and microbial metabolites in the formulation, prolonging the effect of the formulation; at the same time, attapulgite can also adsorb salt in the soil, reduce the degree of soil salinization, and improve the soil microenvironment for root growth.

[0053] 5. Potassium nitrate and boric acid: Potassium nitrate provides nitrogen and potassium to plants. Nitrogen is an important raw material for plant protein synthesis and promotes root cell growth. Potassium can enhance the toughness of plant cell walls and improve the root system's resistance to lodging and drought. Boric acid participates in the reproductive growth and cell wall synthesis of plants and can promote root elongation and lateral root differentiation.

[0054] Source of strain:

[0055] Bacillus desertis (KCTC 33693): purchased from Beijing Bio-Bio Biotechnology Co., Ltd., product number: bio-103968;

[0056] Sonora desert bacillus (X-55-3): purchased from Wuhan Gray Algae Biotechnology Co., Ltd., product number: HZB231597.

[0057] The aforementioned strains were activated and fermented using nutrient agar medium (peptone: 10 g / L, beef meal: 3 g / L, sodium chloride: 5 g / L, agar: 15.0, pH: 7.3 ± 0.1 (25℃)); the culture temperature was 37℃ and the time was 18-24 h.

[0058] Example 1: Preparation of compound microbial agent and sea buckthorn extract

[0059] Preparation of compound bacterial agents: Bacillus desertica and Bacillus sonora were inoculated into nutrient agar medium for activation to obtain Bacillus desertica seed liquid and Bacillus sonora seed liquid respectively;

[0060] Seed cultures of *Bacillus desertica* and *Bacillus sonora* were inoculated onto nutrient agar medium and fermented at 37°C for 24 hours. After fermentation, the cultures were diluted to obtain *Bacillus desertica* bacterial cultures (with an effective viable count of 2 × 10⁻⁶). 8 CFU / mL) and Sonora desert Bacillus bacterial suspension (effective viable count 2×10⁻⁶) 7 (CFU / mL)

[0061] The bacterial cultures of Bacillus desertis and Bacillus sonora are mixed in equal proportions to obtain a compound bacterial agent (in this invention, the mass of 1 mL of the compound bacterial agent is recorded as 1 g).

[0062] Preparation of sea buckthorn extract:

[0063] Sea buckthorn and water were mixed at a ratio of 1g:8mL, extracted at 55℃ for 8 hours, and then filtered to obtain sea buckthorn extract.

[0064] The compound microbial agent and sea buckthorn extract prepared in this embodiment were used in subsequent experiments.

[0065] Example 2

[0066] Weigh the components according to the following mass proportions:

[0067] The mixture consists of 20 parts compound microbial agent, 8 parts sea buckthorn extract, 10 parts potassium humate, 25 parts attapulgite, 12 parts humic acid, 4 parts potassium nitrate, 1.5 parts boric acid, and 80 parts deionized water.

[0068] Preparation of agents to promote root development in desert plants:

[0069] Attapulgite, potassium humate and humic acid were mixed and added to a high-speed mixer. The mixture was stirred at 1800 r / min for 18 min to obtain a composite carrier.

[0070] Sea buckthorn extract, potassium nitrate, boric acid and deionized water were mixed and dissolved in a water bath at 55°C for 10 min, stirred at 900 r / min, and cooled to room temperature to obtain the aqueous phase component.

[0071] The compound microbial agent and the compound carrier were mixed and stirred at 600 r / min for 12 min; the aqueous phase component was slowly added and stirring was continued for 35 min to obtain a preparation that promotes the root development of plants in desert areas.

[0072] Comparative Example 1

[0073] Weigh the components according to the following mass proportions:

[0074] The mixture consists of 22 parts compound microbial agent, 12 parts potassium humate, 27 parts attapulgite, 14 parts humic acid, 4 parts potassium nitrate, 1.5 parts boric acid, and 80 parts deionized water.

[0075] The preparation method of the agent that promotes the root development of plants in desert areas is the same as in Example 2.

[0076] Comparative Example 2

[0077] Weigh the components according to the following mass proportions:

[0078] The mixture consisted of 20 parts of Bacillus desertis bacterial culture, 8 parts of sea buckthorn extract, 10 parts of potassium humate, 25 parts of attapulgite, 12 parts of humic acid, 4 parts of potassium nitrate, 1.5 parts of boric acid, and 80 parts of deionized water.

[0079] The preparation method of the agent that promotes the root development of plants in desert areas is the same as in Example 2.

[0080] Comparative Example 3

[0081] Weigh the components according to the following mass proportions:

[0082] The ingredients included 20 parts of Sonora desert Bacillus bacterial suspension, 8 parts of sea buckthorn extract, 10 parts of potassium humate, 25 parts of attapulgite, 12 parts of humic acid, 4 parts of potassium nitrate, 1.5 parts of boric acid, and 80 parts of deionized water.

[0083] The preparation method of the agent that promotes the root development of plants in desert areas is the same as in Example 2.

[0084] Comparative Example 4

[0085] Weigh the components according to the following mass proportions:

[0086] The ingredients included 18 parts sea buckthorn extract, 15 parts potassium humate, 25 parts attapulgite, 17 parts humic acid, 4 parts potassium nitrate, 1.5 parts boric acid, and 80 parts deionized water.

[0087] The preparation method of the agent that promotes the root development of plants in desert areas is the same as in Example 2.

[0088] Example 1

[0089] The preparations for promoting root development of desert plants obtained in Example 2 and Comparative Examples 1-4 were diluted with water at a ratio of 1g:250mL to obtain root irrigation solutions.

[0090] One-year-old sea buckthorn seedlings were drenched for the first time 8 days after transplanting, with 300 mL applied to each seedling; a second drenching was performed 18 days later, with 300 mL applied to each seedling, and no further drenching was performed. Meanwhile, the watering treatment was used as a control. 100 seedlings were treated with each preparation. The rooting rate of sea buckthorn seedlings was counted 3 months after transplanting, and the survival rate was counted 6 months after transplanting.

[0091] Table 1. Rooting rate and survival rate of different treatments

[0092]

[0093] As shown in Table 1, using water irrigation as a control, the rooting rate of the sea buckthorn seedlings was only 50%, and the survival rate was 48%. However, after root irrigation treatment with the formulation prepared in Example 2, the rooting rate of the sea buckthorn seedlings increased to 78%, and the survival rate significantly increased to 97%, representing increases of 56% and 102.08% respectively compared to the control group. This fully demonstrates that the formulation can effectively promote root development in sea buckthorn seedlings in desert areas and enhance their survival ability in desert environments. Comparing Example 2 with Comparative Example 1, it can be seen that Comparative Example 1, without the addition of sea buckthorn extract and only adjusting the dosage of compound microbial agents and some carriers and nutrient components, had a significantly lower rooting rate (67%) and survival rate (81%) than Example 2. This indicates that sea buckthorn extract is a key component for improving the efficacy of the formulation, and its use in combination with compound microbial agents can produce a synergistic effect. Comparing Example 2 with Comparative Examples 2-3, it can be seen that Comparative Examples 2-3, which can replace the compound microbial agent in Example 2 with single Bacillus desertis inoculum and Bacillus sonora inoculum inoculum respectively, showed significantly lower rooting rates (57%, 60%) and survival rates (77%, 79%) than Example 2. This demonstrates that the compound microbial agent formed by combining the two Bacillus species has better root-promoting and survival-preserving effects than a single species, indicating a synergistic effect between the two species. Comparing Example 2 with Comparative Example 4, it can be seen that Comparative Example 4, which did not add the compound microbial agent but only increased the amount of sea buckthorn extract, carrier, and nutrient components to prepare the formulation, showed a rooting rate (51%) and survival rate (66%) similar to the control group, but significantly lower than Example 2. This directly indicates that the compound microbial agent is the core component for the formulation to exert its root-promoting and survival-preserving effects, and the formulation lacking the compound microbial agent cannot effectively improve the growth performance of sea buckthorn seedlings in desert environments. Based on the above comparative analysis, the reason why the formulation of Example 2 of this application can significantly improve the rooting rate and survival rate of sea buckthorn seedlings in desert areas is due to the combined synergistic effect of Bacillus desertis and Bacillus sonora, as well as the synergistic effect of the compound microbial agent and sea buckthorn extract. Using only a single microbial strain, or only sea buckthorn extract, or adjusting the component ratio but lacking key components, cannot achieve the application effect of the formulation of Example 1.

[0094] Example 2

[0095] The root-promoting agents for desert plant development prepared in Example 2 and Comparative Examples 1-4 were mixed with water at a mass ratio of 1g:5mL to prepare coating solutions. 0.1% sodium carboxymethyl cellulose (sodium carboxymethyl cellulose) by weight of the Haloxylon ammodendron seeds was added and stirred until dissolved. The Haloxylon ammodendron seeds were then added to the coating solution and stirred for 8 minutes to ensure even coating of the seeds. Water was used as a control. 100 seeds were used for each treatment. After drying in a cool, ventilated place, the seeds were sown. The rooting rate of the Haloxylon ammodendron seedlings was recorded two months after sowing, and the survival rate was recorded five months after sowing.

[0096] Table 2. Rooting rate and survival rate of different treatments

[0097]

[0098] As shown in Table 2, the rooting rate of the control group reached 89%, and the survival rate reached 75%, indicating that the Haloxylon ammodendron seeds had a high basic growth level. Under these conditions, the rooting rate of the formulation treatment group in Example 2 reached 100%, and the survival rate increased to 98%, representing increases of 11% and 23% respectively compared to the control group, with increases of 12.36% and 30.67% respectively. This result shows that even in an environment with a good basic growth foundation for the plants, the formulation of Example 2 of this application can still significantly improve the rooting ability and survival ability of Haloxylon ammodendron seedlings in desert areas, demonstrating the stability and superiority of the formulation effect. The rooting rate (91%) and survival rate (85%) of Comparative Example 1 were much lower than those of Example 2, and only slightly higher than those of the control group. This indicates that the sea buckthorn extract is the key component for enhancing the efficacy of the formulation, and its combination with the compound microbial agent can produce a synergistic effect. Simply adjusting the amount of compound microbial agent and carrier cannot achieve the effect of Example 2. Comparative Example 2 (single *Bacillus desertica*) showed a rooting rate of 95% and a survival rate of 81%, while Comparative Example 3 (single *Bacillus sonora*) showed a rooting rate of 90% and a survival rate of 83%. Both sets of data were significantly lower than those of Example 2. This further verifies that the compound microbial agent formed by combining two *Bacillus* species has a better root-promoting and survival-preserving effect than a single species, and there is a complementary and synergistic mechanism between the two species. Comparative Example 4 showed a rooting rate of 93% and a survival rate of 79%, only slightly higher than the control group, and significantly lower than that of Example 2. This proves that the compound microbial agent is an essential component for the formulation to exert its core efficacy. Without the compound microbial agent, even increasing the amount of sea buckthorn extract cannot significantly improve the root-promoting and survival-preserving performance of the formulation. The comparative analysis of the data in Table 2 shows that the formulation of Example 2 is a complete synergistic system of compound microbial agent, sea buckthorn extract, and carrier nutrients. The absence or replacement of any key component (such as sea buckthorn extract or compound microbial agent) (such as a single species replacing the compound microbial agent) will lead to a significant decrease in the efficacy of the formulation. Only by maintaining the combination of the compound microbial agent and sea buckthorn extract, along with carriers such as attapulgite soil and humic acid, and nutritional components, can the rooting rate and survival rate of Haloxylon ammodendron seedlings be maximized. As can be seen, the data in Table 2 further corroborate the scientific validity and effectiveness of the formulation of this invention. Even when the plants are in good basic growth condition, this formulation can still significantly improve the rooting and survival ability of Haloxylon ammodendron seedlings in desert areas, and the synergistic effect of the compound microbial agent and sea buckthorn extract is the core of the formulation's high efficiency.

[0099] Example 3

[0100] In Xinjiang's Taklamakan Desert, planting pits (30cm in diameter and 40cm in depth) were dug. The root development-promoting agents for desert plants prepared in Example 2 and Comparative Examples 1-4 were mixed with topsoil at a mass ratio of 1:12. A water-retaining agent (40% of the agent's dosage) was added, and the mixture was filled into the bottom of the planting pit to a thickness of 6cm. A 3cm layer of soil was then laid on top, and two-year-old Caragana korshinskii seedlings were planted. The soil was backfilled and compacted. The survival rate was recorded 6 months after transplanting.

[0101] Table 3. Rooting rate and survival rate of different treatments

[0102]

[0103] As shown in Table 3, Example 2 had the highest survival rate, significantly higher than the control and Comparative Examples 1-4. This demonstrates that the formulation provided by this invention, when applied via acupoint application, can also achieve the best results.

[0104] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A composition for promoting root development in desert plants, characterized in that, The product comprises the following components by weight: 15-25 parts of compound microbial agent, 5-10 parts of sea buckthorn extract, 8-12 parts of potassium humate, 20-30 parts of attapulgite, 10-15 parts of humic acid, 3-5 parts of potassium nitrate, 1-2 parts of boric acid, and 50-100 parts of deionized water. The compound microbial agent includes Bacillus desertis and Bacillus sonora.

2. The composition according to claim 1, characterized in that, The effective viable count of *Bacillus desertica* and *Bacillus sonora* in the compound microbial agent is 10. 8 10 7 .

3. The composition according to claim 1, characterized in that, The method for preparing the sea buckthorn extract includes the step of mixing sea buckthorn and water and then performing water extraction.

4. The use of the composition according to any one of claims 1-3 in the preparation of an agent that promotes root development of plants in desert areas.

5. A preparation for promoting root development of plants in desert areas, characterized in that, Includes the composition according to any one of claims 1-3.

6. A method for preparing the agent for promoting root development of plants in desert areas as described in claim 5, characterized in that, Includes the following steps: S1. The *Bacillus desertis* and *Bacillus sonora* were fermented and cultured separately, then mixed to obtain the composite bacterial agent; S2. Mix the attapulgite, potassium humate, and humic acid to obtain a composite carrier; S3. The sea buckthorn extract, potassium nitrate, boric acid, and deionized water are mixed to obtain an aqueous phase component; S4. Mix the compound microbial agent, the compound carrier, and the aqueous phase component to obtain the preparation for promoting root development of plants in desert areas.

7. The use of a composition according to any one of claims 1-3 or an agent according to claim 5 for promoting root development of plants in desert areas.

8. The application according to claim 7, characterized in that, The plants include one or more of the following: sea buckthorn, sand fern, caragana, Mongolian euphorbia, and saxaul.

9. A method for promoting root development in desert plants, characterized in that, The step includes applying the agent for promoting root development of desert plants as described in claim 5 to the plants.

10. The method according to claim 9, characterized in that, The application methods include one or more of seed coating, root irrigation, and hole application; The plants include one or more of the following: sea buckthorn, sand fern, caragana, Mongolian euphorbia, and saxaul.

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