Compound microbial agent capable of inhibiting bacterial wilt of solanaceae crops and application of compound microbial agent

Abstract

The invention provides a compound microbial agent capable of inhibiting bacterial wilt of solanaceae crops and application of the compound microbial agent, and belongs to the technical field of microorganisms. The compound microbial agent is mainly prepared by mixing arbuscular mycorrhizal fungi, bacillus subtilis, bacillus licheniformis, bacillus mucilaginosus and saccharomycetes. The compound microbial agent is characterized in that various strains capable of degrading plant root systems and residual branches and fallen leaves are added, degradation of organic matters in soil can be promoted, substance circulation is promoted, plants can obtain more nutrient substances, arbuscular mycorrhizal fungi can resist bacterial wilt infection of solanaceae crops, the arbuscular mycorrhizal fungi can resist bacterial wilt infection of solanaceae crops, and when the arbuscular mycorrhizal fungi are mixed with the strains, the growth of solanaceae crops is promoted. The bacterial wilt can be resisted, the survival rate and the germination rate of crops can be increased, absorption and utilization of plants to nutrient substances in soil can be promoted, and the yield of solanaceae crops can be increased.

Description

Technical Field

[0001] The present invention relates to the technical field of microorganisms, and particularly relates to a composite microbial inoculum capable of inhibiting bacterial wilt of solanaceous crops and its application. Background Art

[0002] Long-term continuous cropping can lead to the accumulation of pathogenic bacteria and plant self-toxins in the soil, causing the occurrence of soil-borne diseases. Among them, bacterial wilt is a common soil-borne disease, which has a great impact on the growth of crops. In severe cases, it can lead to crop yield reduction and economic losses.

[0003] Bacterial wilt is a vascular disease caused by Ralstonia solanacearum, and it is particularly severe during the flowering and fruiting periods of the host. Tomatoes belong to solanaceous crops and are not tolerant to continuous cropping. The extensive use of chemical fertilizers and pesticides has led to an imbalance in the soil microbial population structure, a reduction in the beneficial microbial population, a decrease in soil fertility, crop yield reduction, and a high incidence of bacterial wilt, resulting in a yield loss of nearly 60%-100%. At present, agriculture usually adopts chemical control methods to control bacterial wilt of solanaceous plants: at the initial stage of the disease, 500-fold liquid of 77% copper hydroxide wettable powder, 1500-fold liquid of 86% cuprous oxide wettable powder, 500-fold liquid of 75% chlorothalonil wettable powder, 500-fold liquid of 50% carbendazim wettable powder, 800-fold liquid of 25% bacterial wilt wettable powder, 4000-fold liquid of 72% streptomycin sulfate soluble powder for agricultural use can be used. Each plant is drenched or irrigated with 0.3-0.5 L of the liquid medicine, once every 10 days, and continuously irrigated 2-3 times. However, chemical control is effective in the initial stage of control and ineffective in the later stage of the disease. Once the disease enters the onset stage of bacterial wilt, it is very difficult to find a suitable agent for treatment. Moreover, the long-term use of chemical products such as fungicides and antibiotics will induce the pathogens to produce resistance (tolerance), and will cause environmental pollution. Therefore, biological control has become a safe and effective method for inhibiting bacterial wilt.

[0004] At present, biological control measures are becoming more and more common in integrated disease management, and the biological control effect is beginning to emerge. The root system is the most important place for the interaction between Ralstonia solanacearum and plants. Rhizosphere microorganisms mediate the absorption of nutrients, disease resistance and stress tolerance of plants, and are crucial for plant health and growth and development. At present, biological control methods using soil beneficial microorganisms such as bacteria (such as Flavobacterium, Bacillus and Pseudomonas fluorescens), phages, fungi (such as Trichoderma harzianum and mycorrhizal fungi), etc. account for more than 50% of the relevant research on the prevention and control of bacterial wilt, and are one of the important directions for future prevention and control of Ralstonia solanacearum.

[0005] Arbuscular mycorrhizal fungi (AMF) are the earliest originated and most widely distributed in terrestrial mycorrhizae. They can form mutualistic symbionts with the roots of most plants and are known as the "mother of plant endosymbionts in roots". After AMF infects plants, it will form typical septum-free arbuscules, intra-root hyphae and vesicle structures in the root cortex tissue of plants. The extra-root structures include spores and extra-root hyphae in the soil. Among them, arbuscules are hyphal structures similar to dendritic formed by continuous dichotomous branching after AMF invades the cortical cells of plant roots. They are important sites for the exchange of substances between fungi and plants. The curly structure of arbuscules increases the surface area of their substance exchange. Therefore, the infection rate of arbuscules is often used to evaluate the symbiotic state of AMF-host plants. Research shows that Ralstonia can multiply in large numbers in the vascular bundles, causing the blockage of vessels and the destruction of the entire vessel, resulting in the blockage of vessels and the destruction of the entire vessel as well as the obstruction of nutrient transport, leading to the disease of solanaceous crops. And the intercellular hyphae of the root cells of plants infected by AMF penetrate into the root cells, new entrances appear in the cell walls, and there are numerous cell nuclei and rough endoplasmic reticulum.

[0006] Therefore, in order to reduce the incidence of bacterial wilt in solanaceous plants, it is urgent to develop a compound microbial agent that acts on the rhizosphere of solanaceous plants to resist the infection of Ralstonia solanacearum and effectively prevent and control the occurrence of bacterial wilt in solanaceous plants. Summary of the Invention

[0007] The purpose of the present invention is to provide a compound microbial agent that can inhibit bacterial wilt in solanaceous crops and its application. The compound microbial agent can not only resist bacterial wilt, improve the survival rate and germination rate of crops, but also promote the absorption and utilization of nutrients in the soil by plants, which is beneficial to increasing crop yields.

[0008] In order to achieve the above invention purpose, the present invention provides the following technical solutions:

[0009] The present invention provides a compound microbial agent that can inhibit bacterial wilt in solanaceous crops. The compound microbial agent includes arbuscular mycorrhizal fungi, Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus, and yeast.

[0010] Preferably, the arbuscular mycorrhizal fungi are purchased from the Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Sciences, with the preservation number of BGCHLJ02; the preservation number of Bacillus subtilis subsp. is BNCC 191150; the preservation number of Bacillus licheniformis is BNCC 188032; the Bacillus mucilaginosus is purchased from Wuxi Baifude Biotechnology Co., Ltd. with the preservation number of BM-B10; the preservation number of yeast is CICC 32846.

[0011] Preferably, the volume ratio of Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus, and yeast is 1-2:1-2:1-2:1-2. First, Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus, and yeast are mixed to prepare a mixed microbial agent, and the volume ratio of arbuscular mycorrhizal fungi to the mixed microbial agent is 1-2:1-2..

[0012] Preferably, the concentration of Bacillus subtilis is 2×10 11 CFU / g, the concentration of Bacillus licheniformis is 2×10 11 CFU / g, the concentration of Bacillus mucilaginosus is 4×10 10 CFU / g, the concentration of yeast is 2×10 11 CFU / g, and the concentration of arbuscular mycorrhizal fungi is 1×10 11 CFU / g.

[0013] The present invention also provides an application of the above-mentioned compound microbial agent capable of inhibiting bacterial wilt of solanaceous crops in inhibiting bacterial wilt of solanaceous crops.

[0014] The present invention also provides a microbial bacterial fertilizer capable of inhibiting bacterial wilt of solanaceous crops, and the microbial bacterial fertilizer includes the above-mentioned compound microbial agent capable of inhibiting bacterial wilt of solanaceous crops.

[0015] The beneficial effects of the present invention compared with the prior art are as follows:

[0016] The present invention provides a compound microbial agent capable of inhibiting bacterial wilt of solanaceous crops, which is mainly prepared by mixing arbuscular mycorrhizal fungi, Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus, and yeast. The arbuscular mycorrhizal fungi, Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus, and yeast of the present invention are isolated from the soil, which helps to maintain the stability of the original soil flora. The compound microbial agent is characterized by adding a variety of strains that can degrade the roots of plants and fallen leaves and branches, which can promote the degradation of organic matter in the soil, promote the material cycle, and is beneficial for plants to obtain more nutrients. Among them, the arbuscular mycorrhizal fungi can resist the invasion of bacterial wilt pathogens of solanaceous crops. The mixture of arbuscular mycorrhizal fungi and the above-mentioned strains can not only resist bacterial wilt and improve the survival rate and germination rate of crops, but also promote the absorption and utilization of nutrients in the soil by plants, which is beneficial to increasing the yield of solanaceous crops. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 This is the digital micrograph of the roots of red pearl tomatoes colonized by arbuscular mycorrhizal fungi in Test Example 1 of the present invention;

[0019] Figure 2 This is the digital micrograph of the roots of red pearl tomatoes colonized by arbuscular mycorrhizal fungi under different fields of view in Test Example 1 of the present invention. Detailed implementation manners

[0020] The various exemplary implementation manners 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, characteristics, and implementation manners of the present invention.

[0021] It should be understood that the terms used in the present invention are only for describing particular implementation manners and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0022] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0023] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific implementation manners of the present invention specification, which are obvious to those skilled in the art. Other implementation manners obtained from the present invention specification are obvious to those skilled in the art. The present invention specification and examples are only exemplary.

[0024] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0025] Table 1 Sources of the strains used in the examples

[0026]

[0027] Example 1

[0028] In Example 1 of the present invention, a compound microbial inoculant capable of inhibiting bacterial wilt of solanaceous crops was prepared. The specific steps are as follows:

[0029] Take Bacillus subtilis (specification: 2×10 11 CFU / g), Bacillus licheniformis (specification: 2×10 11 CFU / g), Bacillus mucilaginosus (specification: 4×10 10 CFU / g), and yeast (specification: 2×10 11 CFU / g), mix them in a volume ratio of 1:1:1:1 to obtain a mixed microbial agent, and then mix the mixed microbial agent with arbuscular mycorrhizal fungi (specification: 1×10 11 CFU / g) in a volume ratio of 1:1 to obtain a composite microbial agent that can inhibit bacterial wilt of solanaceous crops.

[0030] Test Example 1

[0031] In Test Example 1 of the present invention, the effect of AMF strains on controlling tomato bacterial wilt was detected. The specific steps are as follows:

[0032] (1) Verify the control effect of AMF on bacterial wilt

[0033] Transplant the seedlings cultivated to the stage of two true leaves and one heart leaf to four true leaves and one heart leaf. During the transplanting process, set a control group (root incision treatment) and an AMF infection group (bury 1 g of sandy soil containing AMF spores at the root incision) and place them in a shaded place for cultivation for 10 days. Then make root incisions and apply Ralstonia solanacearum (Ral.) (purchased from Beijing Baocang Biotechnology Co., Ltd., strain number: BJMCC60145).

[0034] After staining with 0.01% acid fuchsin - lactic acid - glycerol and eluting, observe the plant roots. The results are as Figure 1 shown.

[0035] Use the cross - method to count a large number of results: total colonization rate = (527670) = 78.65%

[0036] Determine the total chlorophyll content of each group by visible light spectrophotometry. The results are shown in Table 1

[0037] Table 1 Chlorophyll content of each group

[0038]

[0039] As can be seen from Table 1, AMF can significantly increase the chlorophyll content of the leaves of Red Pearl tomato plants, which is helpful for the growth of the plants.

[0040] Furthermore, detect the plant height and stem diameter of the seedlings in each group. The results are shown in Table 2:

[0041] Table 2 Plant height and stem diameter of seedlings in each group

[0042]

[0043] Note: One seedling in the Ral. treatment group died and was not counted. The plant height refers to the above-ground part.

[0044] Furthermore, after removing the Red Pearl tomato plants, the Red Pearl tomatoes were replanted in the original soil, and the emergence rate under continuous cropping was counted. The results are shown in Table 3:

[0045] Table 3 Emergence rates of each group

[0046]

[0047] As can be seen from Table 3, AMF has a good control effect on bacterial wilt during the continuous cropping and planting of Red Pearl tomatoes.

[0048] Experimental Example 2

[0049] In Experimental Example 2 of the present invention, the control effect of the compound microbial inoculant prepared in Example 1 was detected. The specific steps are as follows:

[0050] (1) Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus, and yeast inoculants were respectively applied to the Red Pearl tomato seedlings in each group of Experimental Example 1. 2 mL of a 1×10^8 CFU bacterial solution was applied 5 times by punching holes in the soil near the roots at a depth of 2 cm, and the growth status of the Red Pearl tomato seedlings in each group was observed. The growth of the seedlings in each experimental group was better than that of the control group (without applying the bacterial strain).

[0051] (2) The compound microbial inoculant prepared in Example 1 was applied to the Red Pearl tomato seedlings, and the biological characteristics of the growth of the Red Pearl tomato plants in each group were counted. The results are shown in Table 4.

[0052] Table 4 Characteristics of Red Pearl tomato seedlings in each group after applying the compound microbial inoculant prepared in Example 1

[0053]

[0054] As can be seen from Table 4, the compound microbial inoculant of the present invention can significantly reduce the incidence of bacterial wilt and improve the fruit quality and yield.

[0055] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A composite microbial agent capable of inhibiting bacterial wilt of Solanaceae crops, characterized in that: The composite microbial agent comprises arbuscular mycorrhizal fungi, Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus and yeast.

2. The composite microbial agent capable of inhibiting bacterial wilt of Solanaceae crops according to claim 1, characterized in that: The arbuscular mycorrhizal fungi were purchased from the Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Sciences, with the strain collection number BGCHLJ02; the collection number of Bacillus subtilis is BNCC 191150; the collection number of Bacillus licheniformis is BNCC 188032; the strain number of Bacillus mucilaginosus purchased from Wuxi Bayford Biotechnology Co., Ltd. is BM-B10; the collection number of yeast is CICC32846.

3. The composite microbial agent capable of inhibiting bacterial wilt of Solanaceae crops according to claim 1, characterized in that: The volume ratio of the Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus and yeast is 1-2:1-2:1-2:1-2. The Bacillus subtilis, Bacillus licheniformis, Bacillus mucilaginosus and yeast are first mixed to prepare a mixed bacterial agent, and the volume ratio of the arbuscular mycorrhizal fungi to the mixed bacterial agent is 1-2:1-2.

4. The composite microbial agent capable of inhibiting bacterial wilt of Solanaceae crops according to claim 1, characterized in that: The concentration of Bacillus subtilis is 2×10 11 CFU / g, Bacillus licheniformis concentration is 2×10 11 CFU / g, the concentration of Bacillus colloids was 4×10 10 CFU / g, yeast concentration is 2×10 11 CFU / g, the concentration of arbuscular mycorrhizal fungi was 1×10 11 CFU / g.

5. Use of the composite microbial agent capable of inhibiting bacterial wilt of Solanaceae crops as claimed in any one of claims 1 to 4 in inhibiting bacterial wilt of Solanaceae crops.

6. A microbial fertilizer capable of inhibiting bacterial wilt of Solanaceae crops, characterized in that: The microbial fertilizer comprises the composite microbial agent capable of inhibiting bacterial wilt of Solanaceae crops as claimed in any one of claims 1 to 4.

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