Method for improving saline-alkali soil by using arbuscular mycorrhizal fungi fertilizer

Abstract

The application discloses a method for improving saline-alkali soil by using arbuscular mycorrhizal fungi fertilizer, and relates to the technical field of biology.The arbuscular mycorrhizal fungi fertilizer comprises a microbial combination for improving saline-alkali soil; the microbial combination comprises Scopulariopsis brevicaulis, Absidia corymbifera and Eurotium chevalieri.The method for improving saline-alkali soil by using arbuscular mycorrhizal fungi fertilizer is a green, environment-friendly and efficient soil improvement technology, can effectively improve the physical and chemical properties of saline-alkali soil, improve soil quality and crop yield, and has a wide market prospect and important social significance.

Description

Technical Field

[0001] This invention relates to the field of biotechnology, and in particular to a method for improving saline-alkali land using arbuscular mycorrhizal fungal fertilizer. Background Technology

[0002] Saline-alkali land refers to soil containing excessive soluble salts, which restricts crop growth. Saline-alkali land not only affects crop yields but also poses a serious threat to the ecological environment. Therefore, developing effective saline-alkali land improvement technologies has become an urgent need for sustainable agricultural development.

[0003] Currently, common methods for improving saline-alkali land include physical, chemical, and biological measures:

[0004] Physical measures, such as drainage and salt leaching, and deep tillage, can improve soil structure in the short term, but they are costly and the effects are not lasting.

[0005] Chemical measures: such as the application of chemical amendments such as gypsum and ferrous sulfate, although they can quickly reduce soil salinity, long-term use may have negative environmental effects and increase agricultural production costs.

[0006] Biological measures, such as planting salt-tolerant plants and inoculating with rhizobia, are environmentally friendly and sustainable, but their improvement rate is slow and difficult to meet the needs of large-scale agricultural production.

[0007] Arbuscular mycorrhizal fungi (AMF) are a group of soil microorganisms that form symbiotic relationships with most terrestrial plants. They can significantly enhance plant resistance to salt stress, mainly through the following mechanisms:

[0008] Promotes plant absorption of water and nutrients: The AMF mycelial network expands the absorption range of plant roots, improving the efficiency of water and nutrient absorption (such as phosphorus and nitrogen).

[0009] Mitigating salt stress damage: AMF can reduce the damage of salt to plant cells by regulating physiological processes such as osmotic pressure and antioxidant systems within the plant.

[0010] Improving soil structure: The extracellular polysaccharides and other substances secreted by AMF can enhance the stability of soil aggregates and improve soil aeration and water retention.

[0011] To address the shortcomings of existing saline-alkali land improvement technologies, this invention aims to develop a method for improving saline-alkali land using arbuscular mycorrhizal fungi as fertilizer. Summary of the Invention

[0012] The purpose of this invention is to provide a method for improving saline-alkali land using arbuscular mycorrhizal fungi fertilizer, thereby solving the problems existing in the prior art. Using the arbuscular mycorrhizal fungi fertilizer provided by this invention, the physical and chemical properties of saline-alkali soil can be effectively improved, increasing soil quality and crop yield.

[0013] To achieve the above objectives, the present invention provides the following solution:

[0014] This invention provides a microbial ensemble for improving saline-alkali land, including Scoplasticiopsis brevicaulis, Absidia corymbifera, and Eurotium chevalieri.

[0015] The present invention also provides the application of the above-mentioned microbial combination in the preparation of arbuscular mycorrhizal fungal fertilizer.

[0016] The present invention also provides an arbuscular mycorrhizal fungal fertilizer comprising the above-mentioned microbial combination.

[0017] Furthermore, the mass ratio of the bacterial cells of the *Bombyx mori*, the *Pteris vittata*, and the *Sherlocksporium* is 1:2:2.

[0018] Furthermore, the arbuscular mycorrhizal fungal fertilizer also includes a fertilizer carrier.

[0019] Furthermore, the fertilizer carrier is corn stalk powder.

[0020] This invention also provides a method for preparing the above-mentioned arbuscular mycorrhizal fungal fertilizer, comprising the following steps:

[0021] Mix the powders of *Bombyx mori*, *Pteris vittata*, and *Sherlockeus squarrosa* in a mass ratio of 1:2:2 to obtain a mixed fungal powder.

[0022] The corn stalks are crushed and then sieved to obtain corn stalk powder;

[0023] The mixed bacterial powder and the corn stalk powder are mixed evenly to obtain the arbuscular mycorrhizal fungal fertilizer.

[0024] The present invention also provides the application of the above-mentioned microbial combination or arbuscular mycorrhizal fungal fertilizer in the improvement of saline-alkali land.

[0025] The present invention also provides a method for improving saline-alkali land, including the step of applying the above-mentioned arbuscular mycorrhizal fungal fertilizer to the saline-alkali land.

[0026] Furthermore, the method specifically includes the following steps:

[0027] After mixing the red clover seeds with the arbuscular mycorrhizal fungal fertilizer, the mixture was sown in saline-alkali soil. At harvest time, the above-ground part of the red clover was harvested, while the underground part was retained and the soil was tilled.

[0028] The present invention discloses the following technical effects:

[0029] This invention develops an arbuscular mycorrhizal fungal fertilizer that can improve saline-alkali soil. Using this arbuscular mycorrhizal fungal fertilizer can effectively improve the physical and chemical properties of saline-alkali soil, and enhance soil quality and crop yield.

[0030] The method for improving saline-alkali land using arbuscular mycorrhizal fungal fertilizer provided by this invention is a green, environmentally friendly, and efficient soil improvement technology with the following technical advantages:

[0031] The root system of the host plant and the activity of specific AMF species help enhance soil aggregate stability, improve aeration and water retention, enhance plant resistance to salt stress, and promote healthy plant growth. By optimizing the soil environment and plant nutrient supply, they ultimately improve crop yield and quality. As a natural microbial resource, arbuscular mycorrhizal fungi do not pollute the environment and meet the requirements of green agriculture. Compared with traditional physical and chemical improvement methods, arbuscular mycorrhizal fungal fertilizers have lower cost input and higher long-term benefits, making them suitable for large-scale promotion and application.

[0032] In summary, this invention provides an innovative, environmentally friendly, and efficient method for improving saline-alkali land, which has broad market prospects and significant social implications. Detailed Implementation

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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 apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0037] 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.

[0038] To improve saline-alkali soil, this invention develops an arbuscular mycorrhizal fungal fertilizer, which has significant technical effects in improving saline-alkali soil, specifically in the following aspects:

[0039] 1. Adjust soil pH

[0040] AMF can regulate soil pH in multiple ways:

[0041] Acidic metabolites: AMF secretes organic acids during its growth process. These acidic metabolites can neutralize alkaline substances in the soil and lower the soil pH.

[0042] Promotes plant absorption: The AMF mycelial network expands the absorption range of plant roots, improves the absorption efficiency of plants for cations such as calcium and magnesium, reduces the accumulation of these ions in the soil, and thus indirectly lowers the soil pH.

[0043] 2. Reduce soil electrical conductivity (EC)

[0044] High conductivity usually indicates a high content of soluble salts in the soil. AMF can reduce soil conductivity in the following ways:

[0045] Enhancing plant salt tolerance: After forming a symbiotic relationship with plants, AMF can enhance the plants' resistance to salt stress. By regulating the osmotic pressure and antioxidant system within the plant, AMF reduces the damage of salt to plant cells, enabling plants to grow normally in high-salt environments.

[0046] Promotes nutrient absorption: AMF mycelium can effectively absorb nutrients in the soil, especially elements such as phosphorus and potassium, reducing the presence of these nutrients in the soil solution in ionic form, thereby reducing the soil conductivity.

[0047] Improving soil structure: The extracellular polysaccharides and other substances secreted by AMF can enhance the stability of soil aggregates, improve soil aeration and water retention, reduce salt accumulation, and further reduce conductivity.

[0048] 3. Increase soil organic matter content

[0049] During their growth and reproduction, AMF (ammonia pilosa) generates a large amount of biomass, and its remains after death decompose into organic matter, increasing the organic carbon content in the soil. In addition, AMF can also promote the secretion of more rhizosphere deposits (such as sugars and amino acids) by plant roots, which can also be converted into soil organic matter, improving soil fertility and buffering capacity.

[0050] 4. Improve soil microbial community structure

[0051] The presence of AMF alters the composition and function of the soil microbial community, promoting the proliferation of beneficial microorganisms and inhibiting the growth of harmful microorganisms. This not only helps maintain a healthy soil ecosystem but also further improves the physical and chemical properties of the soil through the metabolic activities of microorganisms.

[0052] 5. Enhance soil water retention and aeration.

[0053] The extracellular polysaccharides and other sticky substances secreted by AMF can bind soil particles together to form stable aggregates. This structure not only enhances the soil's water retention capacity but also improves soil aeration, which is beneficial for plant root respiration and growth.

[0054] The strains and culture media used in the following examples are as follows:

[0055] Scoplasticiopsis brevicaulis was purchased from the China Industrial Microbial Culture Collection Center (CICC), strain number CICC 40382; Absidia corymbifera was purchased from the China Industrial Microbial Culture Collection Center, strain number CICC 3151; Eurotium chevalieri was purchased from the China Agricultural Microbial Culture Collection Center (ACCC), strain number ACCC 31813.

[0056] The Glomus mosseae strain was a gift from Professor Zhang Qianbing and has been published in the paper "Enhancing alfalfa photosynthetic performance through arbuscular mycorrhizal fungiinoculation across varied phosphorus application levels".

[0057] The PDA liquid culture medium consists of 200 g / L potato and 20 g / L glucose, with a natural pH.

[0058] The PDA solid culture medium consists of the following components: 200 g / L potato, 20 g / L glucose, and 15 g / L agar powder, with a natural pH.

[0059] Culture medium:

[0060] The components of CYA liquid culture medium are as follows: yeast extract 5.0 g / L, sucrose 30.0 g / L, NaNO3 3.0 g / L, K2HPO4 1.0 g / L, KCl 0.5 g / L, MgSO4·7H2O 0.5 g / L and FeSO4·7H2O 0.01 g / L.

[0061] The components of CYA solid culture medium are as follows: yeast extract 5.0 g / L, sucrose 30.0 g / L, NaNO3 3.0 g / L, K2HPO4 1.0 g / L, KCl 0.5 g / L, MgSO4·7H2O 0.5 g / L, FeSO4·7H2O 0.01 g / L and agar 15.0 g / L.

[0062] The composition of the mold fermentation medium by weight percentage is as follows: molasses 3%, peptone 1%, soybean meal 1.5%, dipotassium hydrogen phosphate 0.5%, potassium dihydrogen phosphate 0.05%, magnesium sulfate 0.03%, and the balance water, pH 6.5.

[0063] Example 1

[0064] 1. The preparation method of *Bombyx mori* powder is as follows:

[0065] (1) Pick a block of short-stemmed broom mold and inoculate it into PDA liquid culture medium. Incubate at 28℃ and 180r / min for 72h to obtain the culture solution.

[0066] (2) Dilute the culture medium obtained in step (1) and spread it on PDA solid culture medium, and incubate it in an incubator at 28°C for 5 days;

[0067] (3) Pick a single colony from the plate in step (2) and inoculate it into an Erlenmeyer flask containing PDA liquid culture medium. Incubate at 28°C and 200 r / min for 48 h with shaking to obtain seed culture.

[0068] (4) The seed liquid obtained in step (3) was transferred to the mold fermentation medium and cultured continuously at 28℃, 210r / min, and 0.05Mpa for 48h to obtain the fermentation broth of *Bombyx mori*. The bacterial cells were obtained by centrifugation and freeze-dried to obtain *Bombyx mori* powder.

[0069] 2. The preparation method of *Pterocarya stenoptera* powder is as follows:

[0070] (1) Select a block of *Pterocarya stenoptera* fungus and inoculate it into PDA liquid culture medium. Incubate at 28℃ and 180r / min for 72h to obtain the culture solution.

[0071] (2) Dilute the culture medium obtained in step (1) and spread it on PDA solid culture medium, and incubate it in an incubator at 28°C for 5 days;

[0072] (3) Pick a single colony from the plate in step (2) and inoculate it into an Erlenmeyer flask containing PDA liquid culture medium. Incubate at 28°C and 200 r / min for 48 h with shaking to obtain seed culture.

[0073] (4) The seed liquid obtained in step (3) was transferred to the mold fermentation medium and cultured continuously at 28℃, 210r / min, and 0.05Mpa for 48h to obtain the fermentation liquid of *Pterocarya stenoptera*. The bacterial cells were obtained by centrifugation and freeze-dried to obtain *Pterocarya stenoptera* powder.

[0074] 3. The preparation method of Sheivasanus mycelium powder is as follows:

[0075] (1) Select a piece of *Sheravas spp.* and inoculate it into CYA liquid medium. Incubate at 28℃ and 180 r / min for 72 h with shaking to obtain the culture medium.

[0076] (2) Dilute the culture medium obtained in step (1) and spread it on CYA solid medium, and incubate it in an incubator at 28°C for 5 days;

[0077] (3) Pick a single colony from the plate in step (2) and inoculate it into an Erlenmeyer flask containing CYA liquid medium. Incubate at 28°C and 200 r / min for 48 h with shaking to obtain seed culture.

[0078] (4) The seed liquid obtained in step (3) was transferred to the mold fermentation medium and cultured continuously at 28℃, 210r / min, and 0.05Mpa for 48h to obtain the fermentation broth of S. Silva, centrifuged to obtain the cell body, and freeze-dried to obtain S. Silva powder.

[0079] 4. Preparation of arbuscular mycorrhizal fungal fertilizer:

[0080] (1) Mix the powders of *Bombyx mori*, *Pteris vittata*, and *Sherlockeus squarrosa* in a mass ratio of 1:2:2 to obtain a mixed fungal powder.

[0081] (2) After crushing the corn stalks, pass them through a 40-mesh sieve to obtain corn stalk powder. Mix the mixed fungal powder and corn stalk powder evenly at a mass ratio of 9:1 to obtain arbuscular mycorrhizal fungal fertilizer.

[0082] Comparative Example 1

[0083] Same as Example 1, except that *Shervasculus* is replaced with *Gastromyxobolus mosie*.

[0084] Comparative Example 2

[0085] Same as Example 2, except that the powder of *Broomella styracifolium* is removed when preparing the mixed bacterial powder.

[0086] Comparative Example 3

[0087] Same as Example 2, except that the *Pteris vittata* powder is removed when preparing the mixed bacterial powder.

[0088] Comparative Example 4

[0089] Same as Example 2, except that the Sheivasanus powder is removed when preparing the mixed bacterial powder.

[0090] Effect verification example

[0091] 1. Test materials

[0092] The experimental field is located at the saline-alkali land experimental base of Shihezi University. The soil texture is saline-alkali, with a salt content of 0.45% and an alkalinity of 17.5%.

[0093] 2. Test Methods

[0094] A method for improving saline-alkali land using arbuscular mycorrhizal fungal fertilizer:

[0095] (1) Red clover seeds were mixed with arbuscular mycorrhizal fungal fertilizer (any one of Example 1 and Comparative Examples 1-4) at a mass ratio of 10:1, and then sown in the saline-alkali experimental field by broadcasting. The sowing amount of red clover seeds was 800g / mu. The control group was not mixed with arbuscular mycorrhizal fungal fertilizer.

[0096] (2) Planting and management should be carried out in accordance with local conventional methods. Harvest the above-ground part of the red clover during the harvest season, retain the underground part, and plow it to a depth of 15cm.

[0097] (3) After plowing, corn is sown using the hole application method, and then planting and management are carried out in accordance with local conventional methods.

[0098] 3. Indicator Testing

[0099] After tillage, the physicochemical properties of the soil in each experimental group were tested. After corn planting, the seed survival rate was recorded during the seedling stage, and the yield per mu (unit of land area) was recorded at the corn maturity stage.

[0100] 4. Test Results

[0101] After tillage, the physicochemical properties of the soil in each experimental group were tested, and the results are shown in Table 1. After corn planting, the seed survival rate was recorded during the seedling stage, and the corn yield per mu (unit of land area) was recorded at the corn maturity stage, and the results are shown in Table 2. The results show that the arbuscular mycorrhizal fungal fertilizer prepared in this invention significantly improved the physicochemical properties of the soil, such as pH and conductivity, and significantly increased soil quality and crop yield. Specifically, the soil pH decreased from 11.07 to 9.13, the conductivity decreased from 4.72 ms / cm to 1.97 ms / cm, and the seedling survival rate and corn yield were significantly improved.

[0102] Table 1. Results of physicochemical property tests for each experimental group

[0103] Group pH Conductivity (ms / cm) Comparison 11.07±0.15 4.72±0.09 Example 1 <![CDATA[9.13±0.21 *** ]]> <![CDATA[1.97±0.06 *** ]]> Comparative Example 1 <![CDATA[10.5±0.20 **## ]]> <![CDATA[3.10±0.38 *# ]]> Comparative Example 2 <![CDATA[9.93±0.25 **# ]]> <![CDATA[2.58±0.14 **# ]]> Comparative Example 3 <![CDATA[10.27±0.15 **## ]]> <![CDATA[3.09±0.15 **## ]]> Comparative Example 4 <![CDATA[9.97±0.12 ***## ]]> <![CDATA[2.87±0.15 **## ]]>

[0104] Note: Compared to the control group, * P<0.05, ** P<0.01, *** P<0.001; compared to Example 1, # P<0.05, ## P<0.01.

[0105] Table 2 Emergence rate and yield of each experimental group

[0106] Group Emergence rate (%) Yield (kg / mu) Comparison 72.5 282 Example 1 95.8 520 Comparative Example 1 82.6 367 Comparative Example 2 78.5 319 Comparative Example 3 81.0 353 Comparative Example 4 76.1 308

[0107] 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 microbial assemblage for improving saline-alkali land, characterized in that, Including short-stemmed broom mold ( Scopulariopsis brevicaulis ), Umbrella branch plowshare mold ( Absidia corymbifera ) and Shevarium ( Eurotium chevalieri ); The strain numbers of *Bombyx mori* and *Pterocarya stenoptera* at the China Industrial Microbial Culture Collection Center are CICC 40382 and CICC 3151, respectively; the strain number of *Schizophyllum septum* at the China Agricultural Microbial Culture Collection Center is ACCC 31813. The mass ratio of the bacterial cells of *Bruscheri styracifolium*, *Pteris vittata*, and *Sherlocksporium styracifolium* is 1:2:

2.

2. The application of the microbial ensemble as described in claim 1 in the preparation of arbuscular mycorrhizal fungal fertilizer.

3. An arbuscular mycorrhizal fungal fertilizer, characterized in that, Includes the microbial assemblages described in claim 1.

4. The arbuscular mycorrhizal fungal fertilizer according to claim 3, characterized in that, The arbuscular mycorrhizal fungal fertilizer also includes a fertilizer carrier.

5. The arbuscular mycorrhizal fungal fertilizer according to claim 4, characterized in that, The fertilizer carrier is corn stalk powder.

6. A method for preparing arbuscular mycorrhizal fungal fertilizer as described in claim 4 or 5, characterized in that, Includes the following steps: Mix the powders of *Bombyx mori*, *Pteris vittata*, and *Sherlockeus squarrosa* in a mass ratio of 1:2:2 to obtain a mixed fungal powder. The corn stalks are crushed and then sieved to obtain corn stalk powder; The mixed bacterial powder and the corn stalk powder are mixed evenly to obtain the arbuscular mycorrhizal fungal fertilizer.

7. The application of a microbial combination as described in claim 1 or an arbuscular mycorrhizal fungal fertilizer as described in any one of claims 3-5 in the improvement of saline-alkali land.

8. A method for improving saline-alkali land, characterized in that, The step includes applying the arbuscular mycorrhizal fungal fertilizer according to any one of claims 3-5 to saline-alkali land.

9. The method according to claim 8, characterized in that, The method specifically includes the following steps: After mixing the red clover seeds with the arbuscular mycorrhizal fungal fertilizer, the mixture was sown in saline-alkali soil. At harvest time, the above-ground part of the red clover was harvested, while the underground part was retained and the soil was tilled.