Development method and application of indigenous bacteria in soil

Abstract

The invention discloses a development method and application of soil indigenous bacteria. The development method of the soil indigenous bacteria comprises the following steps: collecting soil; the method comprises the following steps: preparing a soil suspension from soil and water, inoculating the soil suspension into a culture medium by a gradient dilution method, and separating single colony microorganisms to obtain a plurality of strains; the method comprises the following steps: screening strains which produce indoleacetic acid, produce microbial siderophores, solubilize phosphorus, solubilize potassium and / or have antagonism with soil-borne pathogenic bacteria from various strains to obtain functional strains; bacterial strains with symbiotic and / or synergistic effects are selected from the functional bacterial strains in a mixed culture mode to be compounded, and a composite flora is obtained; single strains in the composite flora or the functional strains are used for soil improvement; the method for developing the indigenous bacteria in the soil has no requirement on the area where the soil is located, the indigenous bacteria can be developed for the soil in any area, the indigenous bacteria highly synergetic with the local soil ecology can be obtained, and the application effect is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of indigenous bacteria, in particular to a development method and application of soil indigenous bacteria. BACKGROUND

[0002] At present, most of the soil microbial agents rely on the introduction of external strains, and there are problems such as poor ecological adaptability to local soil and low colonization efficiency.

[0003] Traditional indigenous bacteria development lacks standardized process, especially in cross-regional application, the screening results are insufficient in repeatability due to the differences in soil type and climate conditions. The existing methods focus on single strain screening, ignoring the synergistic effect of microbial community.

[0004] Therefore, the present application is proposed. SUMMARY

[0005] The purpose of the present application is to provide a development method and application of soil indigenous bacteria, and the development method can obtain indigenous bacteria groups with high ecological synergy to local soil, and improve the application effect.

[0006] In order to achieve the above purpose of the present application, the following technical scheme is adopted:

[0007] The first aspect of the present application provides a development method of soil indigenous bacteria, which comprises the following steps:

[0008] (a) collecting soil by five-point sampling method;

[0009] (b) preparing soil and water into soil suspension liquid, and then inoculating the soil suspension liquid into culture medium by gradient dilution method to separate single colony microorganisms, and obtaining a plurality of strains;

[0010] (c) screening strains with indole acetic acid production, microbial siderophore production, phosphorus solubilization, potassium solubilization and / or antagonistic effect on soil-borne pathogenic bacteria from the plurality of strains, and obtaining functional strains;

[0011] (d) selecting strains with symbiotic and / or synergistic effect from the functional strains by mixed culture to compound, and obtaining a composite microbial community;

[0012] (e) using the composite microbial community or single strain in the functional strains for soil improvement.

[0013] Preferably, in step (a), the depth of the collected soil is 0-20 cm.

[0014] Preferably, in step (b), the culture medium is beef extract peptone culture medium or Gause No. 1 culture medium.

[0015] Preferably, in the step (c), the soil-borne pathogen includes Fusarium and Phytophthora.

[0016] Preferably, in the step (a), the source region of the soil includes Northeast black soil region, North China moist soil region, Yangtze River Basin red soil region, South China lateritic soil region and Northwest Loess Plateau.

[0017] Preferably, in the step (c), the functional strain is further subjected to 16S rRNA or ITS gene sequencing for identification of the functional strain.

[0018] The second aspect of the present application provides a method for developing the soil indigenous bacteria for application in soil improvement.

[0019] The third aspect of the present application provides a method for soil improvement, comprising the following steps:

[0020] (a) determining the functional strain and the composite bacterial community for soil improvement by the method for developing the soil indigenous bacteria;

[0021] (b) adding the functional strain and the composite bacterial community to the soil for soil improvement.

[0022] Compared with the prior art, the present application has at least the following beneficial effects:

[0023] The method for developing the soil indigenous bacteria has no requirement for the region where the soil is located, and can develop the indigenous bacteria for the soil in any region, and obtain the indigenous bacterial community highly coordinated with the local soil ecology, thereby improving the application effect; in addition, the method for developing the soil indigenous bacteria has a standard process from sampling to application, and is convenient for popularization and application in different regions.

[0024] The method for developing the soil indigenous bacteria can avoid the ecological risk caused by introduction of foreign bacteria, and meets the demand for sustainable agricultural development. DETAILED DESCRIPTION

[0025] The technical solutions of the present application will be described in detail below with reference to the embodiments. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, but cannot limit the protection scope of the present application.

[0026] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present application should be understood as the general meanings understood by the persons skilled in the art to which the present application belongs.

[0027] The embodiment of the present application provides a method for developing soil indigenous bacteria, which comprises the following steps:

[0028] (a) collecting soil by five-point sampling method;

[0029] (b) preparing the soil and water into a soil suspension, inoculating the soil suspension into a culture medium by gradient dilution method to separate single colony microorganisms, and obtaining a plurality of strains;

[0030] (c) screening strains with indole acetic acid production, microbial siderophore production, phosphorus solubilization, potassium solubilization and / or antagonistic effect on soil-borne pathogens from the plurality of strains, and obtaining functional strains;

[0031] (d) selecting strains with symbiotic and / or synergistic effect from the functional strains by mixed culture to obtain a compound microbial community;

[0032] (e) applying the compound microbial community or single strain in the functional strains to soil improvement.

[0033] The development method of the soil indigenous bacteria has no requirement for the region where the soil is located, can develop indigenous bacteria for the soil in any region, and can obtain indigenous bacteria groups highly synergistic with local soil ecology, thereby improving the application effect; in addition, the development method of the soil indigenous bacteria has a standard process from sampling to application, and is convenient for popularization and application in different regions.

[0034] The development method of the soil indigenous bacteria can avoid ecological risks possibly caused by introduction of foreign bacteria, and meets the needs of sustainable agricultural development.

[0035] In an embodiment, in the step (a), the depth of the collected soil is 0-20 cm.

[0036] In an embodiment, in the step (b), the culture medium is beef extract peptone culture medium or Gause No. 1 culture medium.

[0037] In an embodiment, in the step (c), the soil-borne pathogen can be a pathogen of a plant planted in the soil, and specifically can include fusarium and pythium.

[0038] In an embodiment, in the step (a), the source region of the soil includes the northeast black soil region, the north China moist soil region, the Yangtze River basin red soil region, the south China lateritic soil region and the northwest loess region.

[0039] In an embodiment, in the step (c), the method further comprises 16S rRNA or ITS gene sequencing of the functional strains, so as to identify the functional strains.

[0040] Another embodiment of the present application provides a soil indigenous bacteria development method for application in soil improvement.

[0041] Still another embodiment of the present application provides a soil improvement method, comprising the following steps:

[0042] (a) determining functional strains and composite microbial flora for soil improvement by using the development method of the soil indigenous bacteria;

[0043] (b) adding the functional strains and composite microbial flora into the soil for soil improvement.

[0044] The technical solutions of the present application are further described in detail through specific examples.

[0045] Example 1

[0046] The present example is a development method of soil indigenous bacteria, which comprises the following steps:

[0047] (a) in the northeast region, corn fields are selected, soil is collected by using five-point sampling method, the soil pH value is 6.8, and the organic matter content is 4.2%;

[0048] (b) the soil and water are prepared into a soil suspension, and then the soil suspension is inoculated into a beef extract peptone culture medium by using gradient dilution method for isolation of single colony microorganisms, thereby obtaining a plurality of strains;

[0049] (c) a strain with an antibacterial rate of 78% against corn large spot bacteria and an IAA production capacity of 35 mg / L is screened from the plurality of strains, and 16S rRNA sequencing is performed on the functional strain for identification of the functional strain;

[0050] (d) the strain with an antibacterial rate of 78% against corn large spot bacteria and an IAA production capacity of 35 mg / L is expanded and then added into the soil for soil improvement.

[0051] The soil is improved according to the above method, and the control soil is not added with the functional strain;

[0052] Corn is planted in the above soil, and then the corn yield and root fresh weight in the improved soil and the control soil are detected, and the results are that the corn yield in the improved soil is increased by 15% and the root fresh weight is increased by 22% compared with the control soil.

[0053] Example 2

[0054] The present example is a development method of soil indigenous bacteria, which comprises the following steps:

[0055] (a) in the south China region, rubber plantations are selected, soil is collected by using five-point sampling method, the soil pH value is 4.5, and the organic matter content is 2.1%;

[0056] (b) The soil and water are formulated into a soil suspension, and the soil suspension is inoculated into beef extract peptone culture medium by gradient dilution method to separate single colony microorganisms, and a plurality of strains are obtained;

[0057] (c) A strain with anti-rubber tree anthracnose fungus and phosphorus solubilizing is screened from the plurality of strains, and a functional strain with an antibacterial rate of 65% against rubber tree anthracnose fungus and a phosphorus solubilizing capacity of 22 mg / L is obtained, 16S rRNA sequencing is performed on the functional strain to identify the functional strain;

[0058] (d) The functional strain with an antibacterial rate of 78% against rubber tree anthracnose fungus and a phosphorus solubilizing capacity of 22 mg / L is expanded and then added to the soil to improve the soil.

[0059] The soil is improved according to the above method, and the control soil is not added with the functional strain;

[0060] The rubber tree disease incidence and latex yield in the improved soil and the control soil are detected, and the results show that the rubber tree disease incidence in the improved soil is reduced by 30% and the latex yield is increased by 8% compared with the control soil.

[0061] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application.

Claims

1. A method for developing a soil indigenous bacteria, characterized by, The method for developing the soil indigenous bacteria comprises the following steps: (a) collecting soil by using five-point sampling method; (b) preparing the soil and water into a soil suspension, inoculating the soil suspension into a culture medium by gradient dilution method to separate single colony microorganisms, and obtaining a plurality of strains; (c) screening strains with the functions of producing indole acetic acid, producing microbial iron carrier, decomposing phosphorus, decomposing potassium and / or having antagonistic effect on soil-borne pathogenic bacteria from the plurality of strains, and obtaining functional strains; (d) selecting strains with symbiotic and / or synergistic effect from the functional strains by mixed culture to compound, and obtaining a composite microbial community; (e) using the composite microbial community or single strain in the functional strains for soil improvement.

2. The development method of soil indigenous bacteria according to claim 1, characterized in that, In the step (a), the depth of the collected soil is 0-20 cm.

3. The development method of soil indigenous bacteria according to claim 1, characterized in that, In the step (b), the culture medium is beef extract peptone medium or Gause No. 1 medium.

4. The development method of soil indigenous bacteria according to claim 1, characterized in that, In the step (c), the soil-borne pathogenic bacteria include fusarium and pythium.

5. The development method of soil indigenous bacteria according to claim 1, characterized in that, In the step (a), the source areas of the soil include Northeast black soil area, North China moist soil area, Yangtze River basin red soil area, South China lateritic soil area and Northwest loess area.

6. The development method of soil indigenous bacteria according to claim 1, characterized in that, In the step (c), the functional strains are further subjected to 16S rRNA or ITS gene sequencing for identification.

7. Application of the method for developing the soil indigenous bacteria according to any one of claims 1-6 in soil improvement.

8. A method of soil improvement, characterized by, The method comprises the following steps: (a) determining the functional strains and the composite microbial community for soil improvement by using the method for developing the soil indigenous bacteria according to any one of claims 1-6; (b) adding the functional strains and the composite microbial community into soil for soil improvement.