Antarctic moesziella MaWFY-1 and application thereof

Abstract

The application discloses a multi-effect plant growth promoting bacterium Moesziomyces antarcticus MaWFY-1 and application thereof. The Moesziomyces antarcticus MaWFY-1 has a preservation number of GDMCC No: 68057. The MaWFY-1 has good adaptability to a rice field environment, can effectively colonize in a rice rhizosphere, and has the functions of dissolving inorganic phosphorus and organic phosphorus, nitrogen fixation and potassium dissolution. The MaWFY-1 is environment-friendly and non-toxic, is inoculated into the rice rhizosphere as a plant growth promoter, has little influence on an ecological environment, and is safe and reliable for rice production and processing. In addition, the MaWFY-1 has low culture condition requirements, is easy to scale, and has a good development and application prospect.

Description

Technical Field

[0001] This invention belongs to the field of plant growth-promoting bacteria technology, specifically relating to a multi-functional plant growth-promoting bacterium, Antarctic Moserella fuciformis MaWFY-1, and its applications. Background Technology

[0002] Rice is one of my country's most important crops. The heavy use of chemical fertilizers and pesticides has been crucial for high rice yields. However, long-term excessive application of these fertilizers and pesticides has not only reduced rice yield and quality but also led to a series of environmental pollution problems. Therefore, developing and utilizing microbial fertilizers to improve the utilization rate of phosphorus fertilizer in rice has become an urgent problem to be solved in rice production, and is of great significance to ensuring my country's food security. Plant growth-promoting fungi (PGPF), as a type of beneficial microorganism, can promote crop growth and nutrient absorption by secreting plant hormones, solubilizing phosphorus, and releasing potassium. They can also help alleviate the adverse effects of stress on crop growth by producing antibiotics, chitinases, and other substances. Compared with traditional chemical fertilizers, PGPF can reduce production costs while mitigating environmental pollution, and is expected to become a key component in green and sustainable agriculture, replacing chemical fertilizers and pesticides.

[0003] While some research has been conducted on plant growth promoters (PGPFs) in the rice rhizosphere, the majority of reports focus on Penicillium, Aspergillus, Trichoderma, and Fusarium fungi due to the complex environmental factors in paddy fields (such as soil type and soil Eh) and limitations of early research techniques. Many plant growth promoters in the rice rhizosphere remain undiscovered, and no studies have reported on the plant growth promoter function of *Ustilago maydis* fungi. Furthermore, although previous studies have reported the ecological functions of PGPFs in some species, these reports primarily focused on the functions of PGPFs in the rhizospheres of other plants such as cucumber, *Eupatorium fortunei*, wheat, pepper, and eggplant, with relatively few studies and reports on the ecological functions of PGPFs in the rice rhizosphere. Therefore, further research on *Ustilago maydis* fungi will deepen our understanding of the diversity and ecological functions of PGPFs in paddy field ecosystems, providing an important foundation for the development and utilization of plant growth promoters in paddy fields.

[0004] *Moesziomyces antarcticus*, belonging to the family Ustilaginaceae and the genus *Moesziomyces*, is a type of smut fungus. Originally discovered in sediments of Lake Vanda in Antarctica, current research indicates that *Moesziomyces antarcticus* has a wide distribution. This fungus can reproduce asexually in soil and lakes, and can also exist symbiotically in the tissues of various gramineous plants such as rice, sugarcane, and barnyard grass. Due to its ability to synthesize some active substances and enzymes, *Moesziomyces antarcticus* is currently widely used in industrial fields. This fungus can produce the natural biosurfactant mannosylerythritol lipid (MEL), which is more easily degraded and environmentally friendly compared to synthetic surfactants. The fungus can also synthesize a plastic-degrading enzyme; the plastic-degrading enzyme produced by strain JCM10317 has been reported to have strong degradation activity against biodegradable plastics such as agricultural mulch films composed of polybutylene succinate and polybutylene adipate. In addition, the lipases A and B produced by this bacterium have been applied in the field of biocatalysis. However, there is currently limited research on Antarctic Moserella in paddy field environments, and no Antarctic Moserella with pleiotropic properties has been reported. Summary of the Invention

[0005] The first objective of this invention is to provide a multifunctional plant rhizosphere growth-promoting bacterium, *Moesziomyces antarcticus* MaWFY-1, which has the functions of solubilizing inorganic and organic phosphorus, fixing nitrogen, and solubilizing potassium. It was deposited on April 7, 2026, at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at 10th Floor, Building 58, No. 100 Xianlie Middle Road, Yuexiu District, Guangzhou, Guangdong Province, 510070, China, with accession number GDMCC No: 68057.

[0006] A second objective of this invention is to provide a microbial inoculum containing the cells of the aforementioned Antarctic Mucor MaWFY-1 and / or its metabolites.

[0007] Preferably, the microbial agent is a microbial fertilizer.

[0008] A third objective of this invention is to provide the application of the aforementioned Antarctic Moserella MaWFY-1 or microbial inoculants in promoting plant growth.

[0009] Preferably, the promotion of plant growth is to promote the growth of plants under nutrient deficiency stress, wherein the nutrient deficiency stress is one or more of phosphorus deficiency, potassium deficiency, and nitrogen deficiency.

[0010] Further preferably, the plant is rice. Even more preferably, the application period is the seedling stage of rice.

[0011] A fourth objective of this invention is to provide the application of the aforementioned Antarctic Moserella MaWFY-1 or microbial agents in promoting the dissolution of inorganic and / or organic phosphorus.

[0012] The fifth objective of this invention is to provide the application of the aforementioned Antarctic Moserella MaWFY-1 or microbial agents in nitrogen fixation.

[0013] The sixth object of the present invention is to provide the application of the above-mentioned Antarctic Moserella MaWFY-1 or microbial agents in potassium solubilization.

[0014] The seventh object of the present invention is a method for promoting plant growth by applying the above-mentioned Antarctic Moserella MaWFY-1 or microbial agents to the plant or its growing environment.

[0015] Preferably, the plant is rice.

[0016] Preferably, the application method is root irrigation.

[0017] The beneficial effects of this invention are as follows:

[0018] This invention marks the first time that *Morrificus antarctica* MaWFY-1 has been isolated from the root system of the rice variety Wufengyou 615 at the Dafeng Base of the Rice Research Institute of the Guangdong Academy of Agricultural Sciences. MaWFY-1 can colonize rice roots well and exhibits good solubility for both inorganic phosphorus (calcium phosphate Ca3(PO4)2) and organic phosphorus (calcium phytate). MaWFY-1 demonstrates good nitrogen fixation and potassium solubilization in the rice rhizosphere, significantly promoting biomass and root growth in rice seedlings under nutrient-deficient stress. Furthermore, MaWFY-1 is environmentally friendly and non-toxic, with minimal impact on the ecological environment, making it safe and reliable. In addition, MaWFY-1 has low cultivation requirements, survives well in soil, and shows great promise for development and application.

[0019] Moesziomyces antarcticus MaWFY-1 was deposited on April 7, 2026, at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at 10th Floor, Building 58, No. 100 Xianlie Middle Road, Yuexiu District, Guangzhou, Guangdong Province, 510070, China, with accession number GDMCC No: 68057. Attached Figure Description

[0020] Figure 1 The identification results of strain MaWFY-1 in Example 1 are shown. A shows the morphology of strain MaWFY-1 on MA medium; B shows the microscopic morphology of strain MaWFY-1; and C shows the phylogenetic tree of MaWFY-1 constructed based on ITS rDNA sequence homology.

[0021] Figure 2The results of the phosphorus solubility characteristics of Antarctic Moserella MaWFY-1 on PVK solid medium in Example 3 are shown. A represents the phosphorus solubility zone produced by MaWFY-1 strain on PVK solid medium supplemented with Ca3(PO4)2 and calcium phytate (cultured for 72 h); B represents the phosphorus solubility of MaWFY-1 strain on Ca3(PO4)2 and calcium phytate under PVK solid culture conditions.

[0022] Figure 3 The results of nitrogen fixation characteristics of Antarctic Moserella MaWFY-1 on Ashby nitrogen-free medium in Example 4 are shown. In this example, A represents the nitrogen-fixing zone produced by MaWFY-1 strain on Ashby nitrogen-free medium (after 7 days of culture); and B represents the nitrogen fixation capacity of MaWFY-1 strain under Ashby nitrogen-free culture conditions.

[0023] Figure 4 The results of potassium solubilization characteristics of Antarctic Moserella MaWFY-1 on silicate medium in Example 5 are shown. In this example, A represents the potassium solubilization zone produced by MaWFY-1 strain on silicate medium (after 7 days of culture); and B represents the potassium solubilization capacity of MaWFY-1 strain under silicate culture conditions.

[0024] Figure 5 The results of Antarctic Moserella MaWFY-1 promoting rice growth in Example 6 are shown. In this example, A represents the difference in rice growth between non-inoculated and inoculated treatments; B represents the effect of non-inoculated and inoculated treatments on the fresh weight of rice; C represents the effect of non-inoculated and inoculated treatments on the root volume of rice; Control and MaWFY-1 represent non-inoculated and inoculated treatments, respectively. Detailed Implementation

[0025] The following are specific implementation examples of the present invention. It should be noted that these embodiments are merely exemplary and do not constitute any limitation on the scope of the present invention. Modifications and substitutions to the details and form of the implementation schemes within the scope and concept of the present invention all fall within the protection scope of the present invention. Unless otherwise defined, the technical terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art. Unless otherwise specified, the experimental reagents used in the following embodiments are conventional biochemical reagents; the experimental methods, unless otherwise specified, are conventional methods.

[0026] Example 1: Isolation, purification, identification and preservation of Antarctic Moraxella fusiforme MaWFY-1

[0027] 1. Experimental Methods

[0028] (1) Preparation of PDA (potato glucose agar medium): Weigh 200 g of potatoes, cut them into small pieces, mix them with 1000 mL of water and boil for 30 min. After filtration, take the filtrate, add 20 g of glucose and 20 g of agar, add deionized water to make up to 1000 mL, set the natural pH value, sterilize at 121℃ for 20 min, cool and store for later use.

[0029] (2) Preparation of MA (Marine Agar Medium): Weigh 5 g of peptone, 1.0 g of yeast extract, 25 g of NaCl, 10.0 g of glucose, and 15.0 g of agar powder. Add deionized water to make up to 1000 mL. Adjust the pH value to 5.5-6.0. Sterilize at 121℃ for 20 min. After cooling, store for later use.

[0030] (3) Sampling: The rhizosphere soil of rice variety Wufengyou 615 was collected from the Dafeng Base of the Rice Research Institute of Guangdong Academy of Agricultural Sciences. The samples were placed in clean sampling bags (bottles), labeled, and stored in a refrigerator at 4℃ for later use.

[0031] (4) Separation and purification: Weigh 100 g of rice rhizosphere soil, dissolve it in 100 mL of sterile water, let it stand for 2 h, and dilute the supernatant 10 times to prepare 10 -1 ~10 -7 Dilute the bacterial suspension. Spread 100 µL of the bacterial suspension onto PDA fungal culture plates and incubate at 28°C for 48-72 h. Pick out the fungal strains, purify and isolate them, and subculture them multiple times.

[0032] (5) Identification: The pure culture strain obtained by the above isolation and purification was transferred to MA medium for fungal morphology identification, and its DNA was extracted and used as a template. The 26S rDNA universal primer was used as a primer to amplify the 26S rDNA nucleotide fragment. The amplified fragment was directly sequenced. The name of the fungal strain was obtained based on the sequenced results and it was deposited in the strain preservation center.

[0033] 2. Experimental Results

[0034] 2.1 Morphological identification

[0035] Pure culture strain MaWFY-1 was isolated and purified. After culturing on MA medium for 3 days, the colonies were milky white with a rough surface and irregular edges; the vegetative cells were oval, exhibiting budding reproduction and containing ascospores, with each ascus containing 1-4 ascospores, and pseudohyphae (…). Figure 1 ).

[0036] 2.2 Molecular Identification

[0037] The amplified 26S rDNA sequence of strain MaWFY-1 was 567 bp in length, and homology comparison showed a homology of 99.77% with *Moesziomyces antarcticus*. Strain MaWFY-1 was named *Moesziomyces antarcticus* MaWFY-1 and deposited on April 7, 2026, at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at 10th Floor, Building 58, No. 100 Xianlie Middle Road, Yuexiu District, Guangzhou, Guangdong Province, 510070, China, with accession number GDMCC No: 68057.

[0038] The 26S rDNA gene sequence (SEQ ID NO.1) of strain MaWFY-1 is as follows: .

[0039] Example 2: Physiological and biochemical characteristics of Antarctic Morphyrus MaWFY-1

[0040] The physiological and biochemical characteristics of strain MaWFY-1 were determined, and the results are shown in Table 1 below.

[0041] Table 1

[0042] Example 3: Phosphate-solubilizing characteristics analysis of Moesziomyces antarcticus MaWFY-1

[0043] Experimental methods

[0044] (1) Preparation of PVK (fungal inorganic phosphorus / organic phosphorus medium): 10.0 g glucose, 0.3 g NaCl, 0.3 g KCl, 0.5 g (NH4)2SO4, 0.3 g MgSO4·7H2O, 0.03 g MnSO4·4H2O, 0.03 g FeSO4·7H2O, 5.0 g Ca3(PO4)2 / calcium phytate, 18 g agar powder, bring the volume to 1000 mL, adjust the pH to 7.0-7.2, sterilize at 121℃ for 20 min, cool and store for later use.

[0045] (2) Determination of phosphorus solubility of Antarctic Moserella MaWFY-1 on PVK solid medium: MaWFY-1 bacterial blocks (block size Φ0.5 cm) were inoculated into PVK solid medium (using Ca3(PO4)2 / calcium phytate as phosphorus source) and cultured at 28℃ for 72 h. The diameter of the colony (d) and the diameter of the phosphorus solubility zone (D) were measured. The ability of MaWFY-1 strain to dissolve Ca3(PO4)2 and calcium phytate was analyzed based on the ratio of the diameter of the phosphorus solubility zone to the diameter of the colony (D / d).

[0046] Experimental results

[0047] like Figure 2 As shown, Antarctic Moserella MaWFY-1 has the ability to dissolve both inorganic phosphorus (Ca3(PO4)2) and organic phosphorus (calcium phytate), which are poorly soluble phosphates.

[0048] Example 4: Analysis of nitrogen fixation characteristics of Moesziomyces antarcticus MaWFY-1

[0049] Experimental methods

[0050] (1) Preparation of Ashby nitrogen-free medium: Weigh 0.2 g of KH2PO4, 5.0 g of CaCO3, 0.2 g of MgSO4·7H2O, 0.2 g of NaCl, 0.1 g of CaSO4·2H2O, and 10.0 g of mannitol. Dissolve them in deionized water and bring the final volume to 1000 mL. Adjust the pH to 7.0, add 15 g of agar powder, and sterilize at 115℃ for 25 min.

[0051] (2) Preparation of single colonies of Antarctic Moserella MaWFY-1: Using a punch, a 0.5 cm mycelial cake was taken from the edge of an Antarctic Moserella MaWFY-1 colony cultured on PDA medium for 5 days and inoculated into Ashby solid medium for activation culture for 7 days.

[0052] (3) Determination of nitrogen fixation characteristics of Antarctic Moserella MaWFY-1 on Ashby solid medium: MaWFY-1 bacterial blocks (block size Φ0.5 cm) were inoculated into Ashby solid medium and cultured at 28℃ for 7 days. The diameter of the colony (d) and the diameter of the nitrogen fixation zone (D) were measured. The nitrogen fixation ability of the MaWFY-1 strain was analyzed based on the ratio of the diameter of the nitrogen fixation zone to the diameter of the colony (D / d).

[0053] Experimental results

[0054] like Figure 3 As shown, Antarctic Moserella MaWFY-1 can form a clear zone in nitrogen-free medium, indicating that the strain has nitrogen-fixing ability.

[0055] Example 5: Analysis of potassium-solubilizing characteristics of Moesziomyces antarcticus MaWFY-1

[0056] Experimental methods

[0057] (1) Preparation of silicate culture medium: Weigh 10.0 g of glucose, 0.3 g of NaCl, 0.3 g of KCl, 0.5 g of (NH4)2SO4, 0.3 g of MgSO4·7H2O, 0.03 g of MnSO4·4H2O, 0.03 g of FeSO4·7H2O, and 2 g of potassium feldspar powder. Make up to 1000 mL with deionized water, adjust the pH value to 7.0-7.2, add 18 g of agar, sterilize at 121℃ for 20 min, cool and store for later use.

[0058] (2) Preparation of single colonies of Antarctic Moserella MaWFY-1: A 0.5 cm mycelial cake was taken from the edge of an Antarctic Moserella MaWFY-1 colony cultured on PDA medium for 5 days using a punch, and then inoculated into silicate medium for activation culture for 7 days.

[0059] (3) Determination of potassium solubilization characteristics of Antarctic Moserella MaWFY-1 on silicate medium: MaWFY-1 bacterial blocks (block size Φ0.5 cm) were inoculated into silicate medium and cultured at 28℃ for 7 days. The diameter of the colony (d) and the diameter of the potassium solubilization zone (D) were measured. The potassium solubilization ability of the MaWFY-1 strain was analyzed based on the ratio of the diameter of the potassium solubilization zone to the diameter of the colony (D / d).

[0060] Experimental results

[0061] like Figure 4 As shown, Antarctic Moserella MaWFY-1 forms potassium-solubilizing zones in silicate medium, indicating that it has significant potassium-solubilizing activity.

[0062] Example 6: Growth-promoting effect of Moesziomyces antarcticus MaWFY-1 on rice seedlings under nutrient-deficient stress

[0063] Experimental methods

[0064] (1) Disinfection and germination of rice seeds: Take an appropriate amount of rice seeds for sterilization. First, soak them in 70% ethanol solution for 1 min, rinse them once with sterile water, soak them in 2.5% sodium hypochlorite solution, sterilize them by shaking at 37℃ for 30 min, and wash them 5-6 times with sterile water. Place the cleaned rice seeds in a sterile petri dish lined with sterile double-layer filter paper and incubate them at 30℃ in the dark for 3 days to allow the seeds to germinate and show white sprouts.

[0065] (2) Preparation of potting substrate: The potting substrate is prepared by mixing paddy soil and sand at a volume ratio of 3:1 (v / v), sterilizing at 121℃ for 20 min, cooling and filling into rice pots according to the ratio, with each pot requiring about 300g of planting substrate.

[0066] (3) Preparation of *Moscone antarctica* MaWFY-1 bacterial suspension: A single colony of the growth-promoting strain was collected, and a 0.5 cm mycelial cake was inoculated into PDA solid medium and activated for 7 days. Fungal spores were gently scraped into 3 mL of sterile water using an inoculation loop. The spores were counted on a microscopic counting plate and equilibrated with sterile water until the spore count was approximately 1.0 × 10⁻⁶. 6 CFU / mL.

[0067] (4) Rice planting and index determination: Take 6 rice seeds from step (1), place them in a rice basin with sterile tweezers, and add a 1.0 × 10⁻⁶ ppm solution. 6 A fungal inoculum solution of CFU / mL was applied to the soil at 2% of the soil mass by root irrigation, with a suspension prepared on a non-inoculated culture medium serving as a control. The rice pots were then placed in an artificial climate chamber where the temperature and light were maintained at approximately 30℃ for 16 hours of light and 24℃ for 8 hours of darkness. After one week, the seedlings were thinned, leaving 3 seedlings per pot. The experiment was completed after approximately 60 days of rice cultivation, and the fresh weight and root volume of the rice were recorded.

[0068] Experimental results

[0069] The results of the potted plant control experiment are as follows Figure 5 As shown, Antarctic Moserella MaWFY-1 has a significant promoting effect on rice biomass and root volume.

Claims

1. A strain of Moesziomyces antarcticus MaWFY-1, characterized in that, The accession number is: GDMCC No: 68057.

2. A microbial inoculant, characterized in that, The bacteria comprising the cells of Antarctic Moraxella MaWFY-1 as described in claim 1 and / or its metabolites.

3. The application of Antarctic Moserella MaWFY-1 as described in claim 1 or the microbial agent as described in claim 2 in promoting plant growth.

4. The application according to claim 3, characterized in that, The promotion of plant growth refers to promoting the growth of plants under nutrient deficiency stress, wherein the nutrient deficiency stress is one or more of phosphorus deficiency, potassium deficiency, and nitrogen deficiency.

5. The application according to claim 4, characterized in that, The plant in question is rice.

6. The use of Antarctic Moserella MaWFY-1 as described in claim 1 or the microbial agent as described in claim 2 in promoting the dissolution of inorganic phosphorus and / or organic phosphorus.

7. The application of Antarctic Moserella MaWFY-1 as described in claim 1 or the microbial agent as described in claim 2 in nitrogen fixation.

8. The application of Antarctic Moraxella MaWFY-1 as described in claim 1 or the microbial agent as described in claim 2 in potassium solubilization.

9. A method for promoting plant growth, characterized in that, Apply the Antarctic Moserella MaWFY-1 as described in claim 1 or the microbial agent as described in claim 2 to the plant or its growing environment.

10. The method according to claim 9, characterized in that, The plant in question is rice, and the application method is root irrigation.

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