A strain of salt- and heavy metal-tolerant Deinococcus and its application in rice and wheat

Abstract

The present invention provides a salt-resistant and heavy metal-resistant Deinococcus and its application in rice and wheat, belonging to the technical field of microorganism-plant interaction and its application. Deinococcus sp. )NH1, deposited in China Center for Type Culture Collection on July 22, 2024, with the deposit address: Wuhan University, Wuhan, China; the deposit number is CCTCC NO: M 20241625; a microbial agent, comprising the Deinococcus ( Deinococcus sp. )NH1; the Deinococcus ( Deinococcus sp. ) Application of NH1 or the above-mentioned microbial agents in promoting plant growth.

Description

Technical Field

[0001] The invention belongs to the technical field of microorganism-plant interaction and application thereof, and specifically relates to a salt-resistant and heavy metal-resistant Deinococcus and application thereof in rice and wheat. Background Art

[0002] As an important component of the soil ecosystem, microorganisms have multiple functions such as symbiosis with plants, promoting plant growth, and improving plant resistance. Studies have shown that some specific microorganisms can provide plants with essential nutrients through processes such as nitrogen fixation, phosphorus solubilization, and potassium solubilization. At the same time, they can also secrete some beneficial biologically active substances, such as plant hormones and antioxidant enzymes, which can effectively improve the resistance of plants to adverse stress. In addition, microorganisms can also form a protective film on the surface of plant roots, thereby preventing heavy metals from being absorbed by plants, reducing the damage of heavy metals to plants, and reducing the accumulation of heavy metals in plants. Some microorganisms not only have good salt tolerance, but also help plants improve their ability to resist salt stress, so that they can survive in high-salt environments. In recent years, with the rapid development of biotechnology, the method of using microorganisms to improve the resistance of rice and wheat to heavy metals and salt stress has gradually attracted people's attention.

[0003] Research has found that bacteria of the genus Deinococcus have an efficient DNA repair system and antioxidant protection system, as well as abundant reducing substances in the cells, which enable them to not only withstand high-intensity radiation, but also have strong tolerance to a variety of heavy metal ions. Deinococcus bacteria have been reported to be used to reduce chromate and bromate in wastewater, and to use genetic engineering methods to transfer their target genes into recipient organisms to improve the recipient organism's resistance to stress. Deinococcus radiodurans In R1 trkA The gene (DR1666) can enhance the drought resistance of prokaryotic host cells and rapeseed by transferring them. However, using genetic engineering to improve the stress resistance of plants is time-consuming and technically difficult, which limits its application in production. There is no report in the prior art on directly applying Deinococcus to plants to improve their stress resistance without genetic engineering technology. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides a salt-tolerant and heavy metal-tolerant Deinococcus and its application in rice and wheat.

[0005] The inventors screened a strain of Deinococcus bacteria from the soil and named it Deinococcus ( Deinococcus sp. )NH1, the study found that the strain has good resistance to salt and heavy metal stress. In LB medium, the strain has a tolerance to NaCl of 60 g / L and a tolerance to Cd 2+Can withstand 150 mg / L CdCl2 and Ni 2+ It can tolerate 130 mg / L NiCl2. Co-culturing Deinococcus NH1 with rice and wheat seedlings can effectively improve the resistance of rice and wheat to abiotic stresses such as heavy metals and salt.

[0006] The technical solution of the present invention is as follows:

[0007] A Deinococcus Deinococcus sp. )NH1 was deposited in the China Center for Type Culture Collection on July 22, 2024. The deposit address is: Wuhan University, Wuhan, China; the deposit number is CCTCC NO: M 20241625.

[0008] A microbial agent comprising the above-mentioned Deinococcus ( Deinococcus sp. )NH1.

[0009] The above Deinococci ( Deinococcus sp. ) Application of NH1 or the above-mentioned microbial agents in promoting plant growth.

[0010] According to the present invention, preferably, the above-mentioned Deinococcus ( Deinococcus sp. ) Application of NH1 or the above-mentioned microbial agents to promote plant growth in an abiotic stress environment.

[0011] Further preferably, in the application, abiotic stress includes the following:

[0012] Heavy metal stress;

[0013] Salt stress;

[0014] Heavy metal and salt stress.

[0015] More preferably, in the application, the heavy metal includes one or more of cadmium, nickel and copper.

[0016] According to a preferred embodiment of the present invention, in the application, the plants include Gramineae.

[0017] Further preferably, in the application, the plants include rice and wheat.

[0018] The beneficial effects of the present invention include at least the following:

[0019] 1. The Deinococcus provided by the present invention ( Deinococcus sp. ) NH1 can promote plant growth and can improve the growth of plants under abiotic stress conditions such as heavy metals and salt, such as rice and wheat.

[0020] 2. The strain described in the present invention will not cause any harm to rice and wheat seedlings, can coexist with rice and wheat, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The Deinococcus provided by the present invention ( Deinococcus sp. ) Colony image of NH1 on LB solid medium.

[0022] Figure 2 Deinococcus Deinococcus sp. ) Optimal pH diagram of NH1 in LB liquid medium.

[0023] Figure 3 Deinococcus Deinococcus sp. )NH1 to Cd 2+ Tolerance curve diagram.

[0024] Figure 4 Deinococcus Deinococcus sp. )NH1 to Ni 2+ Tolerance curve diagram.

[0025] Figure 5 Deinococcus Deinococcus sp. ) NH1 salt tolerance curve;

[0026] Because LB medium itself contains 10 g / L NaCl, the NaCl concentration marked in the figure is the concentration of additionally added NaCl.

[0027] Figure 6 To apply the Deinococcus aureus ( Deinococcus sp. ) Statistical results of physiological and biochemical indicators when the cells grew to the 30th day after NH1.

[0028] Figure 7 The Deinococcus aureus ( Deinococcus sp. ) Statistical results of physiological and biochemical indicators when the cells grew to the 15th day after NH1.

[0029] Figure 8 The Deinococcus aureus ( Deinococcus sp. ) Statistical results of physiological and biochemical indicators when the cells grew to the 15th day after NH1.

[0030] Figure 9 The Deinococcus aureus ( Deinococcus sp. ) Statistical results of physiological and biochemical indicators when the cells grew to the 15th day after NH1.

[0031] Figure 10 The Deinococcus aureus ( Deinococcus sp. ) Statistical results of physiological and biochemical indicators when the cells grew to the 15th day after NH1.

[0032] Figure 11 To apply the Deinococcus aureus ( Deinococcus sp. ) The growth status and root system status results after growing to the 30th day after NH1.

[0033] Figure 12 The Deinococcus aureus ( Deinococcus sp. ) The growth status and root system status results on the 15th day after growth with NH1.

[0034] Figure 13 The Deinococcus aureus ( Deinococcus sp. ) The growth status results after growing for 15 days after NH1.

[0035] Figure 14 The Deinococcus aureus ( Deinococcus sp. ) The growth status results after growing for 15 days after NH1.

[0036] Figure 15 The Deinococcus aureus ( Deinococcus sp. ) The growth status results after growing for 15 days after NH1. DETAILED DESCRIPTION

[0037] The present invention is described in detail below with reference to the embodiments, but the protection scope of the present invention is not limited thereto.

[0038] All matters not described in detail in the embodiments are based on the prior art in the art.

[0039] Example 1

[0040] Deinococcus Deinococcus sp. ) Isolation and purification of NH1

[0041] 1 g of soil sample from the rice experimental field in Gao'an, Jiangxi Academy of Agricultural Sciences (28°26′N, 115°14′E) treated with long-term fertilization was added to 10 mL of sterile water and mixed to make 10 -1 Dilution, pipette 1 mL 10 -1 Add the diluent to 9 mL of sterile water and mix well to make 10 -2 Dilution, and so on to make 10 -3 , 10 -4 , 10 -5 , 10 -6 Dilution, take 10 -3 , 10 -4 , 10 -5 , 10 -6The diluted solution was spread on LB solid medium (sodium chloride: 10 g / L; peptone: 10 g / L; yeast powder: 5 g / L; agar powder: 15 g / L) and cultured at 28 °C.

[0042] Single colonies with different morphological characteristics were selected for purification, and the growth-promoting properties of the screened strains were determined. The strains with the most growth-promoting properties were selected, and one of them was named NH1 and stored in a glycerol tube.

[0043] Example 2

[0044] Deinococcus Deinococcus sp. ) Identification of NH1

[0045] (1) Morphological, physiological and biochemical characteristics of the strain

[0046] Deinococcus Deinococcus sp. ) The colony morphology of NH1 on LB solid plate is as follows Figure 1 As shown, the Deinococcus ( Deinococcus sp. ) NH1 is a Gram-positive bacterium with round colonies of 1-3 mm in diameter. The bacteria are red and opaque with a smooth and moist surface without halos and a slight bacterial odor. The suitable growth temperature for this bacterium is 25-37 ℃.

[0047] Prepare LB liquid medium (chlorinated sodium : 10 g / L; peptone: 10 g / L; yeast powder: 5 g / L) were divided into 50 mL conical flasks, 20 mL in each bottle. The pH was adjusted with NaOH solution and HCl solution to 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, respectively, and sterilized at 121 ℃ for 15 min. After it was cooled to room temperature, NH1 bacterial suspension was added at a ratio of 2%. Each conical flask was placed on a shaker at 28 ℃ and 180 rpm for 24 h, and the absorbance at 600 nm was measured. Figure 2 As shown, the optimal growth pH of the bacteria is about 6.5, and it can grow normally in LB liquid culture medium with a pH of 5.5-8.

[0048] (2) Identification of the 16S rRNA gene of the strain

[0049] The genome of strain NH1 was extracted using a genome extraction kit and used as a template to amplify the 16S rDNA sequence using 16S rRNA universal primers 27F (5'-GAGAGTTTGATCCTGGCTCAG-3' SEQ ID NO.2) and 1492R (5'-ACGGATACCTTGTTACGACTT-3' SEQ ID NO.3).

[0050] The PCR reaction system was (25 μL): 10× buffer 2.5 μL, dNTP 2 μL, upstream primer 27F 0.5 μL, downstream primer 1492R 0.5 μL, Taq enzyme 0.15 μL, DNA template 1 μL, ultrapure water 18.35 μL. The PCR program was: 94 °C pre-denaturation for 10 min, 94 °C denaturation for 40 s, 53 °C annealing for 40 s, 72 °C extension for 90 s, 35 cycles, 72 °C extension for 10 min, 10 °C insulation. The results of 1% agarose gel electrophoresis showed that the single size of the PCR product band was about 1.5 kb. The PCR product was sent to Qingdao Ruiboxingke Sequencing Company for sequencing. The sequencing results are shown in the nucleotide sequence of SEQ ID NO.1 in the sequence list. The sequencing results were compared on NCBI (https: / / www.ncbi.nlm.nih.gov / ) and it was found that the sequence similarity between the strain and Deinococcus was 100%, so the strain was judged to be Deinococcus. The present invention screened Deinococcus ( Deinococcus sp. ) NH1 was deposited in the China Center for Type Culture Collection on July 22, 2024. The deposit address is: Wuhan University, Wuhan, China; the deposit number is CCTCC NO: M 20241625.

[0051] Example 3

[0052] Deinococcus Deinococcus sp. ) Preparation of NH1 bacterial suspension

[0053] The Deinococcus ( Deinococcus sp. ) The method for preparing the bacterial suspension of NH1 includes the following steps: inoculating the purified strain NH1 into LB liquid culture medium (sodium chloride: 10 g / L; peptone: 10 g / L; yeast powder: 5 g / L) at a 1% inoculation rate, culturing in a constant temperature shaking incubator at 28°C and 180 rpm for 24 h, transferring the strain fermentation liquid to a sterilized centrifuge tube, centrifuging at 8000 rcf for 10 min at room temperature, then carefully discarding the supernatant, resuspending the bacteria with sterile distilled water, measuring OD600, adjusting the absorbance at 600 nm to 0.25, and obtaining the NH1 bacterial suspension for use.

[0054] Example 4

[0055] Deinococcus Deinococcus sp. )NH1Cd 2+ Tolerance test

[0056] The Deinococcus ( Deinococcus sp. )NH1Cd 2+The tolerance test method includes the following steps: a total of 11 treatment groups were set up in the experiment, and 20 mL of LB liquid culture medium (sodium chloride: 10 g / L; peptone: 10 g / L; yeast powder: 5 g / L) was added to 50 mL conical flasks respectively, and then CdCl2 mother liquor was added respectively, so that the CdCl2 concentration in each treatment was 0 mg / L, 5 mg / L, 10 mg / L, 15 mg / L, 20 mg / L, 40 mg / L, 60 mg / L, 100 mg / L, 150 mg / L, 200 mg / L, and 250 mg / L. All treatment groups were sterilized in an autoclave at 121 ° C for 15 min. When the temperature of the culture medium of each treatment group was lower than 35 ° C, the NH1 bacterial suspension prepared in Example 3 was inoculated into the above culture medium at an inoculum amount of 2% by volume in a clean bench. The OD600 values ​​were measured at 24 h, 48 h, 72 h, and 96 h in a constant temperature shaking incubator at 28 °C and 180 rpm. Figure 3 .Depend on Figure 3 It can be seen that Deinococcus ( Deinococcus sp. ) NH1 can tolerate 150 mg / L CdCl2, and when the CdCl2 concentration is ≤10 mg / L, it is effective against Deinococcus ( Deinococcus sp. ) There was no obvious inhibition on the growth of NH1.

[0057] Example 5

[0058] Deinococcus Deinococcus sp. ) NH1 Ni 2+ Tolerance test

[0059] The Deinococcus ( Deinococcus sp. ) NH1 Ni 2+ The tolerance test method includes the following steps: a total of 9 treatment groups were set up in the experiment, and 20 mL of LB liquid culture medium (sodium chloride: 10 g / L; peptone: 10 g / L; yeast powder: 5 g / L) was added to 50 mL conical flasks respectively, and then NiCl2 mother liquor was added respectively, so that the NiCl2 concentration in each treatment was 0 mg / L, 30 mg / L, 60 mg / L, 75 mg / L, 90 mg / L, 105 mg / L, 115 mg / L, 130 mg / L, and 160 mg / L. All treatment groups were sterilized in an autoclave at 121 ° C for 15 min. When the culture medium temperature of each treatment group was lower than 35 degrees Celsius, the NH1 bacterial suspension prepared in Example 3 was inoculated into the above culture medium at an inoculum amount of 2% by volume in a clean bench. The OD600 was measured at 24 h, 48 h, 72 h and 96 h in a constant temperature shaking incubator at 28 °C and 180 rpm. Figure 4 .Depend onFigure 4 It can be seen that Deinococcus ( Deinococcus sp. ) NH1 can tolerate 130 mg / L NiCl2, and when NiCl2 concentration is ≤90 mg / L, it is effective against Deinococcus ( Deinococcus sp. ) There was no obvious inhibition on the growth of NH1.

[0060] Example 6

[0061] Deinococcus Deinococcus sp. ) Salt tolerance experiment of NH1

[0062] The Deinococcus ( Deinococcus sp. ) The salt tolerance experimental method of NH1 includes the following steps: a total of 11 treatment groups were set up in the experiment, and 20 mL of LB liquid culture medium (sodium chloride: 10 g / L; peptone: 10 g / L; yeast powder: 5 g / L) was added to 50 mL conical flasks respectively, and then NaCl solid was added respectively, so that the NaCl concentration added in each treatment was 0 g / L, 5 g / L, 10 g / L, 15 g / L, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L, and 50 g / L (LB culture medium itself contains 10 g / L of NaCl, so the NaCl concentration marked here is the additional NaCl concentration). All treatment groups were sterilized in an autoclave at 121 ° C for 15 min. When the culture medium temperature of each treatment group was lower than 35 degrees Celsius, the NH1 bacterial suspension prepared in Example 3 was inoculated into the above culture medium at an inoculum amount of 2% by volume in an ultra-clean workbench. The OD600 values ​​were measured at 24 h, 48 h and 72 h in a constant temperature shaking incubator at 28 °C and 180 rpm. Figure 5 .Depend on Figure 5 It can be seen that Deinococcus ( Deinococcus sp. )NH1 has a salt tolerance of 60 g / L, and is effective against Deinococcus when the salt concentration is ≤20 g / L ( Deinococcus sp. ) There was no obvious inhibition on the growth of NH1.

[0063] Example 7

[0064] Deinococcus Deinococcus sp. ) Experiment on cadmium tolerance and growth promotion of soil-cultured rice seedlings with NH1

[0065] Four treatment groups were set up in the experiment, namely control treatment (CK), single inoculation of bacteria treatment (NH1), single inoculation of cadmium treatment (Cd), and cadmium stress + bacteria treatment (Cd+NH1); the rice seeds were sterilized and germinated at 28 °C for 5 days, and rice seedlings with the same growth status were selected and divided into 4 groups, with 20 plants in each group. They were placed in 7 cm culture dishes, and 15 mL of sterile water was added to the control group (CK) and the single inoculation of cadmium treatment group (Cd); 15 mL of OD prepared in Example 3 was added to the single inoculation of bacteria treatment group (NH1) and cadmium stress + bacteria treatment (Cd+NH1). 600 = 0.25 of bacterial suspension, and soaked the roots for 1 h. After soaking the roots, the rice seedlings were planted in seedling pots with 100 g of soil. The control treatment (CK) was added with 10 mL of sterile water, and the single inoculation treatment (NH1) was added with 5 mL of OD prepared in Example 3. 600 = 0.25 bacterial suspension and 5 mL sterile water, single cadmium treatment (Cd) added 5 mLCdCl2 solution and 5 mL sterile water to make the final CdCl2 concentration of the soil 5 mg / kg, cadmium stress + bacterial treatment (Cd+NH1) added 5 mL CdCl2 solution 5 mL bacterial suspension, so that the final CdCl2 concentration of the soil is 5 mg / kg. Cultivate in a greenhouse (28 ℃ / 16 h light and 26 ℃ / 8 h dark) and water in time to keep the pot soil moist. Samples were taken on the 30th day of growth of rice seedlings to measure various physiological indicators. Statistical results of rice physiological and biochemical indicators can be found in Figure 6 The growth status and root status of rice on the 30th day are as follows: Figure 11 As shown. Figure 6 As shown, under cadmium stress conditions, Deinococcus ( Deinococcus sp. )NH1 bacterial suspension effectively alleviated the restrictions on rice growth and physiological activity, as shown by a significant increase in the biomass (total fresh weight, plant height, and root length) of rice seedlings compared to those not inoculated with bacteria, an increase in chlorophyll content, and a significant decrease in the activities of peroxidase (POD) and catalase (CAT) in rice leaves, indicating that the restrictions on rice growth and physiological activity caused by cadmium stress were alleviated.

[0066] The experimental results show that the bacterial suspension can promote the growth of rice seedlings under cadmium stress and alleviate the damage caused by cadmium stress to rice seedlings.

[0067] Example 8

[0068] Deinococcus Deinococcus sp. ) Experiment on nickel tolerance and growth promotion of hydroponic rice seedlings with NH1

[0069] Four treatment groups were set up in the experiment, namely control treatment (CK), single inoculation of bacteria treatment (NH1), single inoculation of nickel treatment (Ni), and nickel stress + bacteria treatment (Ni+NH1); the rice seeds were sterilized and germinated at 28 ℃ for 5 days, and rice seedlings with the same growth status were selected and divided into 4 groups, with 15 plants in each group. They were placed in 7 cm culture dishes, and 15 mL of sterile water was added to the control group (CK) and the single inoculation of nickel treatment group (Ni); 15 mL of OD prepared in Example 3 was added to the single inoculation of bacteria treatment group (NH1) and nickel stress + bacteria treatment (Ni+NH1). 600 = 0.25 bacterial suspension, soak the roots for 1 h. After soaking the roots, the rice seedlings were placed in planting baskets with a diameter of 7 cm, and the planting baskets were placed in 600 mL milk tea cups. 360 mL of sterilized Hoagland nutrient solution (purchased from Haibo Biotechnology Co., Ltd., used according to the instructions) was added to the milk tea cups. The nutrient solution just covered the seedlings. 10 mL of sterilized Hoagland nutrient solution was added to the control treatment (CK), and 5 mL of OD prepared in Example 3 was added to the single inoculation treatment (NH1). 600 = 0.25 bacterial suspension and 5 mL sterilized Hoagland nutrient solution, single nickel treatment (Ni) added 5 mL NiCl2 stock solution and 5 mL sterilized Hoagland nutrient solution to make the final NiCl2 concentration of 30 mg / L, nickel stress + bacteria treatment (Ni+NH1) added 5 mL NiCl2 stock solution and 5 mL bacterial suspension to make the final NiCl2 concentration of 30 mg / L. Cultured in a light incubator (28 ℃ / 16 h light and 26 ℃ / 8 h dark), the culture medium was replaced every two days, and nickel stress and bacterial agents were applied in the above proportions to ensure stable growth conditions of rice in each treatment group. Samples were taken on the 15th day of growth of rice seedlings to measure various physiological indicators. Statistical results of rice physiological and biochemical indicators can be found in Figure 7 The growth status and root status of rice on the 15th day are as follows: Figure 12 As shown. Figure 7 As shown, under nickel stress conditions, Deinococcus ( Deinococcus sp. ) The biomass of rice seedlings inoculated with NH1 bacterial suspension was significantly increased in terms of plant height, root length, fresh weight, etc., the number of main roots larger than 1 cm in rice seedlings increased, the peroxidase (POD) activity of rice leaves was significantly decreased, and the catalase (CAT) activity was significantly increased, indicating that the restriction of rice growth and physiological activity caused by nickel stress was alleviated.

[0070] The experimental results show that the bacterial suspension can promote the growth of rice seedlings under nickel stress and alleviate the damage caused by nickel stress to rice seedlings.

[0071] Example 9

[0072] Deinococcus Deinococcus sp.) Experiment on cadmium tolerance and growth promotion of hydroponic wheat seedlings using NH1

[0073] Four treatment groups were set up in the experiment, namely control treatment (CK), single inoculation of bacteria treatment (NH1), single inoculation of cadmium treatment (Cd), and cadmium stress + bacteria treatment (Cd+NH1); the wheat seeds were sterilized and germinated at 28 °C for 5 days, and wheat seedlings with the same growth status were selected and divided into 4 groups, with 15 plants in each group. They were placed in 7 cm culture dishes, and 15 mL of sterile water was added to the control group (CK) and the single inoculation of cadmium treatment group (Cd); 15 mL of OD prepared in Example 3 was added to the single inoculation of bacteria treatment group (NH1) and cadmium stress + bacteria treatment (Cd+NH1). 600 = 0.25 bacterial suspension, soak the roots for 1 h. After soaking the roots, place the wheat seedlings in planting baskets with a diameter of 7 cm, and place the planting baskets in 600 mL milk tea cups. Add 360 mL of sterilized Hoagland nutrient solution (purchased from Haibo Biotechnology Co., Ltd. and used according to the instructions) to the milk tea cups. Add 10 mL of sterilized Hoagland nutrient solution to the control treatment (CK), and 5 mL of OD prepared in Example 3 to the single inoculation treatment (NH1). 600 = 0.25 bacterial suspension and 5 mL sterilized Hoagland nutrient solution, single cadmium treatment (Cd) added 5 mL CdCl2 mother solution and 5 mL sterilized Hoagland nutrient solution to make the final CdCl2 concentration of 45 mg / L, cadmium stress + bacteria treatment (Cd+NH1) added 5 mL CdCl2 mother solution and 5 mL bacterial suspension to make the final CdCl2 concentration of 45 mg / L. Cultured in a light incubator (28 ℃ / 16 h light and 26 ℃ / 8 h dark), the culture medium was replaced every two days, and cadmium stress and bacterial agents were applied in the above proportions to ensure stable growth conditions for wheat in each treatment group. Samples were taken on the 15th day of wheat seedling growth to measure various physiological indicators. Statistical results of wheat physiological and biochemical indicators can be found in Figure 8 The growth status of wheat on the 15th day is as follows Figure 13 As shown. Figure 8 As shown, under cadmium stress conditions, Deinococcus ( Deinococcus sp. ) The biomass (total fresh weight, plant height, and root length) of wheat seedlings inoculated with NH1 bacterial suspension was significantly higher than that of wheat seedlings not inoculated with bacteria, and the number of main roots larger than 1 cm was significantly increased. The peroxidase (POD) and catalase (CAT) levels of wheat leaves were reduced, indicating that the limitation of wheat growth and physiological activity caused by cadmium stress was alleviated.

[0074] The experimental results show that the bacterial suspension can promote the growth of wheat seedlings under cadmium stress and alleviate the damage caused by cadmium stress to wheat seedlings.

[0075] Example 10

[0076] Deinococcus Deinococcus sp. ) Experiment on copper tolerance and growth promotion of hydroponic wheat seedlings using NH1

[0077] Four treatment groups were set up in the experiment, namely control treatment (CK), single inoculation of bacteria treatment (NH1), single inoculation of copper treatment (Cu), copper stress + bacteria treatment (Cu+NH1); the wheat seeds were sterilized and germinated at 28 ℃ for 5 days, and wheat seedlings with the same growth status were selected and divided into 4 groups, with 15 plants in each group. They were placed in 7 cm culture dishes, and 15 mL of sterile water was added to the control group (CK) and the single inoculation of copper treatment group (Cu); 15 mL of OD prepared in Example 3 was added to the single inoculation of bacteria treatment group (NH1) and copper stress + bacteria treatment (Cu+NH1). 600 = 0.25 bacterial suspension, soak the roots for 1 h. After soaking the roots, place the wheat seedlings in planting baskets with a diameter of 7 cm, and place the planting baskets in 600 mL milk tea cups. Add 360 mL of sterilized Hoagland nutrient solution (purchased from Haibo Biotechnology Co., Ltd. and used according to the instructions) to the milk tea cups. Add 10 mL of sterilized Hoagland nutrient solution to the control treatment (CK), and 5 mL of OD prepared in Example 3 to the single inoculation treatment (NH1). 600 = 0.25 bacterial suspension and 5 mL sterilized Hoagland nutrient solution, single copper treatment (Cu) added 5 mL CuSO4 stock solution and 5 mL sterilized Hoagland nutrient solution to make the final CuSO4 concentration of 80 mg / L, copper stress + bacteria treatment (Cu+NH1) added 5 mL CuSO4 stock solution and 5 mL bacterial suspension to make the final CuSO4 concentration of 80 mg / L. Cultured in a light incubator (28 ℃ / 16 h light and 26 ℃ / 8 h dark), the culture medium was replaced every two days, and copper stress and bacterial agents were applied in the above proportions to ensure stable growth conditions for wheat in each treatment group. Samples were taken on the 15th day of wheat seedling growth to measure various physiological indicators. Statistical results of wheat physiological and biochemical indicators can be found in Figure 9 The growth status of wheat on the 15th day is as follows Figure 14 As shown. Figure 9 As shown, under high copper stress conditions, Deinococcus ( Deinococcus sp. ) The biomass (total fresh weight, plant height, and root length) of wheat seedlings inoculated with NH1 bacterial suspension was significantly higher than that of wheat seedlings not inoculated with bacteria, and the number of taproots larger than 1 cm was increased.

[0078] The experimental results show that the bacterial suspension can promote the growth of wheat seedlings under cadmium stress and alleviate the damage caused by copper stress to wheat seedlings.

[0079] Embodiment 11

[0080] Deinococcus Deinococcus sp.) Experiment on salt tolerance and growth promotion of hydroponic wheat seedlings using NH1

[0081] Four treatment groups were set up in the experiment, namely control treatment (CK), single inoculation of bacteria treatment (NH1), single inoculation of salt treatment (Na), and salt stress + bacteria treatment (Na+NH1). After the wheat seeds were sterilized, they were germinated at 28 °C for 5 days, and wheat seedlings with the same growth status were selected and divided into 4 groups, with 15 plants in each group. They were placed in 7 cm culture dishes, and 15 mL of sterile water was added to the control group (CK) and the single inoculation of salt treatment group (Na); 15 mL of OD prepared in Example 3 was added to the single inoculation of bacteria treatment group (NH1) and salt stress + bacteria treatment (Na+NH1). 600 = 0.25 bacterial suspension, soak the roots for 1 h. After soaking the roots, place the wheat seedlings in planting baskets with a diameter of 7 cm, and place the planting baskets in 600 mL milk tea cups. Add 360 mL of sterilized Hoagland nutrient solution (purchased from Haibo Biotechnology Co., Ltd. and used according to the instructions) to the milk tea cups. Add 10 mL of sterilized Hoagland nutrient solution to the control treatment (CK), and 5 mL of OD prepared in Example 3 to the single inoculation treatment (NH1). 600 = 0.25 bacterial suspension and 5 mL sterilized Hoagland nutrient solution, single salt treatment (Na) added 5 mL NaCl stock solution and 5 mL sterilized Hoagland nutrient solution to make the final NaCl concentration 9 g / L, salt stress + bacteria treatment (Na+NH1) added 5 mL NaCl stock solution and 5 mL bacterial suspension to make the final NaCl concentration 9 g / L. Cultured in a light incubator (28 ℃ / 16 h light and 26 ℃ / 8 h dark), the culture medium was replaced every two days, and salt stress and bacterial agents were applied in the above proportions to ensure stable growth conditions for wheat in each treatment group. Samples were taken on the 15th day of wheat seedling growth, and various physiological indicators were measured. Statistical results of wheat physiological and biochemical indicators can be found in Figure 10 The growth status of wheat on the 15th day is as follows Figure 15 As shown. Figure 10 As shown, under salt stress conditions, Deinococcus ( Deinococcus sp. ) The biomass (total fresh weight, plant height, and root length) of wheat seedlings inoculated with NH1 bacterial suspension was significantly higher than that of wheat seedlings not inoculated with bacteria, the number of main roots larger than 1 cm was significantly increased, and the activities of peroxidase (POD) and catalase (CAT) in wheat leaves were reduced, indicating that the limitation of wheat growth and physiological activity caused by salt stress was alleviated.

[0082] In addition to the above results, under soil culture conditions, the Deinococcus provided by the present invention ( Deinococcus sp.)NH1 can also effectively increase the chlorophyll content of rice under copper stress. Compared with the chlorophyll content of rice under copper stress, when the copper sulfate content in the soil was 30 mg / kg, the chlorophyll content of rice in the treatment group treated with NH1 strain increased by 26.5%. However, other physiological and biochemical indicators did not change significantly. The Deinococcus provided by the present invention ( Deinococcus sp. )NH1 cannot effectively alleviate the adverse effects of cobalt stress on the growth of wheat seedlings under hydroponic conditions.

[0083] In summary, the Deinococcus provided by the present invention ( Deinococcus sp. ) NH1 not only has good resistance to salt and heavy metals cadmium and nickel, but also has a plant growth-promoting effect. Applying it to the rhizosphere of rice and wheat seedlings can effectively improve the resistance of rice and wheat to abiotic stresses such as heavy metals and salt, and reduce the damage caused by such abiotic stresses to rice and wheat seedlings.

Claims

1. A Deinococcus species ( Deinococcus sp. )NH1 was deposited in the China Center for Type Culture Collection on July 22, 2024. The deposit address is: Wuhan University, Wuhan, China; the deposit number is CCTCC NO: M 20241625.

2. A microbial agent, characterized in that: comprising the Deinococcus according to claim 1 ( Deinococcus sp. )NH1.

3. The Deinococcus according to claim 1 ( Deinococcus sp. ) Use of the microbial agent described in NH1 or claim 2 in promoting the growth of rice and wheat.

4. The use according to claim 3, characterized in that The Deinococcus according to claim 1 ( Deinococcus sp. ) Use of the microbial agent described in NH1 or claim 2 to promote the growth of rice and wheat in an abiotic stress environment; The abiotic stress is heavy metal stress; salt stress; heavy metal and salt stress; The heavy metal is one or more of cadmium, nickel and copper.

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