Efficient corn straw composite degrading bacterium DF and application thereof
By using a composite strain of Bacillus belyssus and Bacillus amyloliquefaciens, the problems of low utilization rate and environmental pollution of corn straw have been solved, achieving efficient degradation and resource recycling of straw.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INNER MONGOLIA AGRICULTURAL UNIVERSITY
- Filing Date
- 2025-12-15
- Publication Date
- 2026-05-12
AI Technical Summary
Existing technologies suffer from low utilization rates of corn stalks and environmental pollution, and the degradation effect of a single strain is unstable.
A composite bacterial strain of Bacillus velezensis HW-124 and Bacillus amyloliquefaciens HW-130 in a 1:1 ratio was used to improve the straw degradation rate through synergistic effects. The composite bacterial solution was then inoculated onto the straw surface for degradation.
It significantly improves the degradation rate of straw, enhances straw utilization, is environmentally friendly and efficient, has a clear degradation effect, and promotes straw return to the field.
Smart Images
Figure CN122012267A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of microbial technology, and in particular to a highly efficient corn stalk degrading bacterium DF and its applications. Background Technology
[0002] Corn is the most widely planted grain crop in my country for many years, and corn stalks account for a high proportion of total crop straw resources. Although corn stalk resources are abundant, the actual utilization rate is only about 40%. Corn stalks are rich in lignocellulose, mainly including cellulose, hemicellulose, and lignin. If these components can be fully degraded, they can be broken down into small molecules and nutrients that can be returned to the soil for crop absorption and utilization, achieving sustainable resource recycling. However, the lignocellulose structure is interlocked and complex, making it difficult to fully degrade under natural field conditions. Therefore, the low comprehensive utilization rate of corn stalks is a key problem that urgently needs to be solved in current agricultural production.
[0003] Biodegradation utilizes microorganisms to disrupt the main structure of lignocellulose, thereby promoting straw degradation. This process not only achieves rapid and efficient degradation but also offers environmental benefits, avoiding potential pollution from chemical treatments and saving on labor and machinery costs associated with physical processes. Compared to single strains, composite microbial strains significantly enhance the degradation capacity of lignocellulose in straw, resulting in a more pronounced promoting effect. Screening for degradative composite microbial communities is crucial in crop straw degradation research and is an indispensable means of promoting the effective utilization of crop straw resources. Therefore, it is necessary to screen and cultivate composite microbial communities with highly efficient straw degradation capabilities to address the aforementioned challenges. Summary of the Invention
[0004] The technical problem to be solved by this invention is to overcome the problems of low utilization rate and environmental pollution in the existing straw treatment methods, and to provide a highly efficient corn straw composite degrading bacteria DF and its application.
[0005] The technical solution adopted to solve the above technical problems is: a highly efficient corn straw composite degrading bacteria DF, wherein the composite degrading bacteria DF is composed of Bacillus belysinus (… Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens HW-130; the aforementioned Bacillus belesia ( Bacillus velezensis HW-124 has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC NO.7.626 and deposit date of December 3, 2025; the described Bacillus amyloliquefaciens ( Bacillus AmyloliquefaciensHW-130 has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC NO.7.625 and deposit date of December 3, 2025.
[0006] Furthermore, the aforementioned Bacillus belye ( Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens The composite ratio of HW-130 is 1:1.
[0007] Furthermore, the application of the compound degrading bacteria DF in the degradation of crop straw.
[0008] Furthermore, the crops mentioned include corn, rice, wheat, potatoes, and sorghum.
[0009] The beneficial effects of this invention are as follows: This invention uses Bacillus belye ( Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens HW-130 and Bacillus amyloliquefaciens work synergistically to significantly improve the degradation rate of straw. The degradation process involves inoculating a composite bacterial solution prepared by mixing the two single-strain bacterial solutions at a 1:1 ratio into an enzyme-producing liquid culture medium, and then uniformly contacting the treated straw surface with the resulting bacterial solution. Bacillus bellis HW-124 and Bacillus amyloliquefaciens HW-130 have the ability to efficiently degrade corn straw and work synergistically to significantly improve straw utilization and promote straw return to the field. Attached Figure Description
[0010] Figure 1 This is a graph showing the degradation rate of straw fermentation experiment using the single strain HW-124 of this invention.
[0011] Figure 2 This is a graph showing the degradation rate of straw fermentation experiment using a single strain of HW-130.
[0012] Figure 3 This is a bar chart showing the changes in DF cellulase activity in the complex bacteria.
[0013] Figure 4 This is a graph showing the degradation rate of corn straw in a pot experiment using compound bacteria DF.
[0014] Figure 5 This is a graph showing the degradation rate curve of corn straw in a pot experiment using compound bacteria DF and commercial bacterial agents.
[0015] Figure 6 This is a scanning electron microscope image of straw treated with water (CK).
[0016] Figure 7 This is a scanning electron microscope image of straw treated with DF (diethyltoluene) compound bacteria.
[0017] Figure 8 This is a scanning electron microscope image of straw treated with the commercial preservative CF1.
[0018] Figure 9 This is a scanning electron microscope image of straw treated with the commercial preservative CF2. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0020] The composite degrading bacteria DF in this embodiment is composed of Bacillus vesiculosus (Belaseinus) Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens HW-130, Bacillus belysinus ( Bacillus velezensis HW-124 has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC NO.7.626 and deposit date of December 3, 2025. (Bacillus amyloliquefaciens) Bacillus Amyloliquefaciens HW-130 has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC NO.7.625 and deposit date of December 3, 2025. (Bacillus belye) Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens The composite ratio of HW-130 is 1:1.
[0021] The application of compound degrading bacteria DF in the degradation of crop straw, including corn, rice, wheat, potatoes, and sorghum. Bacillus berreatus HW-124 and Bacillus amyloliquefaciens HW-130 have a high capacity for degrading corn straw, working synergistically to significantly improve straw utilization and promote straw return to the field.
[0022] Bacillus belesiensis ( Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens HW-130 and the other two work synergistically to significantly improve the straw degradation rate. The degradation process is carried out by inoculating a compound bacterial solution prepared by mixing the two single-strain bacterial solutions at a 1:1 ratio into an enzyme-producing liquid culture medium, and then uniformly contacting the bacterial solution of a certain concentration with the treated straw surface.
[0023] Strains were enriched and isolated from soil where straw has been returned to the field for many years. After initial screening with Congo red and secondary screening through straw fermentation experiments, their degradation rate was determined, resulting in a single lignocellulose-degrading strain. Morphological, physiological, biochemical, and molecular biological identifications were performed. Different compound bacterial combinations were constructed at a 1:1 ratio, and the compound bacterial strain with the highest cellulase activity was selected. Its cellulase activity was measured within 7 days of growth. The compound bacterial solution was evenly sprayed onto corn straw for a pot experiment simulating a field, and the degradation rate was measured. Scanning electron microscopy was used to investigate the degradation effect. Finally, based on these results, a compound degrading bacterium with highly efficient degradation ability for corn straw was obtained and named DF.
[0024] In this embodiment, the two single bacteria in the composite degrading bacteria composition produce cellulase after acting on straw, synergistically breaking down the dense structure of the straw, entering the interior of the structure, digesting and utilizing the lignocellulose components, and improving the overall degradation rate. The carboxymethyl cellulase activity of the composite degrading bacteria DF reaches its peak on the 4th day of cultivation. The compound bacterial DF showed a straw degradation rate of 43.40% after 45 days of potted plant degradation, which was 3.2 times that of the control (CK). The microscopic morphological changes of the straw after 45 days of potted plant degradation were significant under an electron microscope. The straw structure after degradation by the compound bacterial DF was severely damaged, with obvious decomposition pores and a high degree of decay. The compound bacterial DF of this invention is environmentally friendly, efficient, and non-toxic, and has good application prospects in the utilization of agricultural waste.
[0025] Currently, there are three main methods for promoting effective in-situ straw return to the field: physical, chemical, and biological treatments. Physical treatment involves breaking down straw into small pieces using mechanical methods, such as crushing, to disrupt its rigid lignocellulose structure and increase the contact area between the straw and the soil, thereby improving the straw degradation rate. Chemical treatment involves fermenting the straw or adding exogenous chemicals to gradually break down its complex fiber structure, promoting degradation, such as biogas fermentation technology. Biological treatment utilizes microbial degrading bacteria to absorb and utilize lignocellulose, breaking down its structure and decomposing it into smaller molecules and nutrients. This not only enhances straw degradation but also indirectly promotes the cycling of available nutrients between the soil and straw, thus promoting crop growth and development. Compared to the previous two methods, biological treatment reduces the input of manpower and machinery and avoids potential chemical residues and pollution to the soil and crops at the source. Degrading bacteria are naturally occurring organisms that adapt well to the soil microenvironment and can remain active for a longer period, thus exerting a stronger degradation effect. The composite microorganisms exhibit stronger stability and degradation capabilities. Therefore, by screening out composite degrading bacteria with strong degradation properties and good stability, it is possible to achieve efficient degradation of corn straw, thereby improving resource utilization and promoting effective in-situ straw return to the field. The development of this technology solves the potential problems and shortcomings of physical and chemical straw treatment methods, such as the instability of single-strain performance, thus protecting the agricultural ecological environment.
[0026] The specific method for obtaining the composite degrading bacteria DF in this embodiment is as follows: S1, Enrichment, Isolation, and Purification of Degrading Strains: Soil samples were collected from 5-10 cm below the surface in Arong Banner, Hulunbuir City, Inner Mongolia Autonomous Region using a five-point sampling method and passed through a 1 mm sieve. The soil sources were: farmland soil treated with organic fertilizer (cow dung) and soil from fields where corn stalks had been returned year-round. 10 g of each sample was weighed and placed in an Erlenmeyer flask, and 90 mL of sterile water was added. The flasks were then incubated at 30°C using a constant temperature shaking incubator. Shake for 30 minutes, place in a clean bench and let stand for 30 minutes. Dilute the supernatant to 10 using a dilution gradient method. -2 10 -3 10 -4 10 -5 10 -6 10 -7 10 -8Seven concentrations were prepared, with 100 μL of liquid evenly spread on LB solid medium (bacterial medium), PDA medium (fungal medium), and Gao's No. 1 medium (actinomycete medium). Each concentration was repeated three times. The cultures were incubated upside down in a constant temperature incubator at 30°C, and the growth was observed daily. After the emergence of single colonies, each single colony with different morphologies was picked up with an inoculation loop and streaked. The process of picking and streaking was repeated for each strain until a purified strain was obtained.
[0027] S2, Congo red staining method for initial bacterial screening: Under aseptic conditions, isolated single strains were picked and inoculated onto sodium carboxymethyl cellulose selection medium plates. Each plate was inoculated three times, with the three spots forming an equilateral triangle. Each strain was repeated three times. After incubation at 30°C upside down until colonies appeared, 1 mg / mL of [amount missing] was added to the medium. -1 Apply Congo red staining solution until it just covers all colonies on the plate, and let it stand for 30 minutes. After complete staining, discard the staining solution and add an equal volume of 1 mol·L⁻¹. -1 The bacteria were decolorized in NaCl solution and allowed to stand for 20 minutes. The diameters of the colonies and the surrounding clear zone were observed and measured, and recorded as h and H, respectively. The H / h value was calculated, and the ratio of H to h reflects the degradation ability of the strain. Strains with strong degradation ability were screened with H / h > 1.5 for further investigation.
[0028] Results: White transparent halos formed around the colonies of strains HW-124 and HW-130, with the ratios (H / h) of the halos diameter to the colony diameter being 3.92 and 5.59, respectively. This demonstrates that these two single strains possess a certain ability to hydrolyze cellulose, thus yielding two single strains with cellulose degradation capabilities.
[0029] Table 1 shows the hydrolysis results of Congo red for strains HW-124 and HW-130 (data in the table are average ± SD): Table 1
[0030] The method for determining the DF of the compound degrading bacteria in this embodiment is as follows: (1) Degradation rate determination of straw liquid fermentation experiment: Take well-grown strains and inoculate them into LB liquid medium to prepare bacterial suspension. Different bacterial suspensions were inoculated into liquid fermentation medium with corn straw as the sole carbon source at a concentration of 9% (V / V). An equal volume of sterile water was used as a control. Each treatment was repeated three times. The mixture was incubated at 30°C for 35 days. On days 0, 5, 15, 25, and 35 of fermentation, the straw and its residue in the Erlenmeyer flasks were removed, rinsed with running tap water, and repeatedly washed with sterile water. The residues were then dried at 80°C to constant weight and weighed to calculate the degradation rate of the corn straw.
[0031] Corn stalk degradation rate (%) = (Y1-Y2) / Y1×100 Where Y1 is the dry weight (g) of corn stalks before fermentation, and Y2 is the dry weight (g) of corn stalks after fermentation.
[0032] The results are as follows Figure 1 , Figure 2 As shown, the straw degradation rate of strains HW-124 and HW-130 increased with the increase of fermentation time, reaching the maximum on day 35 of fermentation, at 49.38% and 52.5% respectively, which were much higher than those of the CK control group, further verifying that the above single strains have good straw degradation ability.
[0033] (2) Single-strain cellulase activity assay: The carboxymethyl cellulase activity of the strains was determined using the DNS method. HW-124 and HW-130 cells were inoculated into culture medium to prepare bacterial suspensions, which were then inoculated into liquid enzyme-producing medium at 9% (V / V) and cultured at 30℃ and 180 r / min in a shaker to obtain bacterial solutions. The bacterial solutions were centrifuged at 4000 r / min for 10 min, and the supernatant was used as crude enzyme solution.
[0034] In the enzyme activity calculation formula described above, X is the glucose content (mg) obtained from the glucose standard curve, N is the dilution factor of the enzyme solution, T is the time of the enzyme-catalyzed reaction (min), and A is the volume of enzyme solution added (mL).
[0035] The specific procedure for the DNS method is as follows: Take four clean test tubes of the same size, one as a blank and the other three as test tubes (repeat three times). Accurately weigh 1.5 mL of 1% CMC-Na standard solution and add it to each of the four test tubes. Add 0.5 mL of diluted crude enzyme solution to each test tube, shake well, and place all test tubes in a 50℃ constant temperature water bath for 30 min. Then, add 0.5 mL of boil-inactivated diluted crude enzyme solution to the blank tube, shake well, and immediately add 1.5 mL of DNS reagent to each test tube. Boil in a water bath for 10 min, remove and cool to room temperature, add 10 mL of distilled water, shake well, and let stand. Measure the absorbance at 540 nm using a UV spectrophotometer. Then, determine the reducing sugar content according to the glucose standard curve, and then calculate the carboxymethyl cellulase activity.
[0036] The specific method for obtaining the above glucose curves is as follows: Dry, clean test tubes were numbered 0-8, and different volumes of distilled water and glucose standard solution were added to each tube to obtain glucose solutions of different concentration gradients. Then, 1.5 mL of DNS reagent was added, and the solutions were thoroughly mixed and boiled in a water bath for 10 min. After cooling to room temperature, 10 mL of distilled water was added to each test tube. After mixing, the optical density of the solution in each test tube was measured using a UV spectrophotometer at a wavelength of 540 nm. The OD values for each group were plotted with glucose content (mg) on the x-axis. 540 Using the values as the ordinate, a glucose standard curve is plotted.
[0037] Result: The equation for the glucose standard curve obtained is as follows: The maximum carboxymethyl cellulase activities of strains HW-124 and HW-130 during their growth from day 1 to day 7 were calculated. The enzyme activities showed a trend of first increasing and then decreasing with increasing culture time. Strain HW-124 exhibited the maximum enzyme activity of 20.21 U·mL on day 6 of culture. -1 The strain HW-130 exhibited its maximum enzyme activity of 29.64 U·mL on day 5 of culture. -1 This indicates that the strain has the ability to produce cellulase to degrade cellulose.
[0038] (3) Morphological identification of strains HW-124 and HW-130: The bacterial solutions of strains HW-124 and HW-130 were diluted by the dilution gradient plating method and spread on LB solid medium. They were incubated upside down at 30°C until complete single colonies grew, and the morphology of the strains was observed.
[0039] Results: Strain HW-124 was an opaque, milky white, nearly circular colony with a dry surface, a raised center, and irregularly serrated, wrinkled edges; strain HW-130 was a translucent, pale yellow, circular colony with a moist surface, a thick center, and thin, smooth edges.
[0040] (4) Physiological and biochemical identification of strain HW-130: The physiological and biochemical characteristics of the strain were identified with reference to the "Handbook of Systematic Identification of Common Bacteria", including tests on malonate utilization, methyl red test, amylase activity, lipase activity, nitrate, oxidase and catalase activity.
[0041] Results: Strains HW-124 and HW-130 are Gram-positive bacteria exhibiting some characteristics of the Cellulomonas genus, such as glucose homogenization, nitrate reduction, and starch hydrolysis, indicating that these two strains possess similar good cellulose degradation capabilities to this genus. Compared to strain HW-124, HW-130 exhibits additional lipase and catalase activity and can utilize lactose and fructose.
[0042] As shown in Table 2, the physiological and biochemical indicators of strain HW-130 are as follows ("+" indicates positive and "-" indicates negative): Table 2
[0043] (5) Molecular biological identification of strain HW-130: Genomic DNA of strain HX-130 was amplified by PCR using universal primers 27F and 1492R, performed by Beijing Pofansenno Biotechnology Co., Ltd. The sequencing results were compared for homology using BLAST (https: / / blast.ncbi.nlm.nih.gov) in the National Center for Biotechnology (NCBI) database. A phylogenetic tree was constructed using MEGA 11.0 software based on the Neighbor-Joining (NJ) method with a 1000-fold bootstrapping algorithm.
[0044] Amplification primers used: 27F 5'-AGAGTTTGATCCTGGCTCAG-3' 1492R 5'-CTACGGCTACCTTGTTACGA-3' The PCR amplification reaction system was as follows: genomic DNA (20 ng / μl) -1 1.0 μl; 10× Buffer (containing 2.5 mM Mg) 2+ 5.0 μl; extaq 0.25 μl; dNTP(10mM) 2.0 μl; 1 μl of 27F primer (10 uM); 1492R primer (10 uM) 1 μl; ddH2O 39.75 μl; Total volume 50.0 μl.
[0045] Results: Phylogenetic trees of strains HW-124 and HW-130 were constructed using MEGA 11.0 software based on 16S rDNA sequences. Strains HW-124 and Bacillus belye (…) Bacillus velezensis They clustered together, with the accession number (PQ288756.1) being the most closely related; strain HW-130 was related to Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens The strains clustered together, with the accession number (OP753626.1) being the most closely related. Based on the above morphological and physiological / biochemical identification results, strains HW-124 and HW-130 were determined to be *Bacillus belye* (…). Bacillus velezensis ), Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens ).
[0046] (6) Antagonism test between single strains HW-124 and HW-130: One strain was inoculated onto LB agar plates containing the other strain by punching holes in the plates, and incubated upside down at 30°C. The experiment was repeated 3 times. If a clear inhibition zone appeared at the intersection of the two strains, they were antagonistic; otherwise, they were not antagonistic. The larger the inhibition zone, the more obvious the antagonistic effect.
[0047] Results: There was no antagonistic effect between the single strains HW-124 and HW-130, and both strains were able to grow.
[0048] (7) Construction of the compound bacterial DF and determination of cellulase activity: The carboxymethyl cellulase activity of the compound bacterial DF was determined by the DNS method after 7 days of culture, and the determination was performed every 24 h. The compound bacterial suspension was prepared and inoculated into liquid enzyme-producing medium at 9% (V / V) and cultured in a shaker at 30℃ and 180 r / min to obtain the bacterial solution. The bacterial solution was centrifuged at 4000 r / min for 10 min, and the supernatant was used as crude enzyme solution.
[0049] In the enzyme activity calculation formula described above, X is the glucose content (mg) obtained from the glucose standard curve, N is the dilution factor of the enzyme solution, T is the time of the enzyme-catalyzed reaction (min), and A is the volume of enzyme solution added (mL).
[0050] The specific procedure for the DNS method is as follows: Take four clean test tubes of the same size, one as a blank and the other three as test tubes (repeat three times). Accurately weigh 1.5 mL of 1% CMC-Na standard solution and add it to each of the four test tubes. Add 0.5 mL of diluted crude enzyme solution to each test tube, shake well, and then place all test tubes in a 50℃ constant temperature water bath for 30 min. Next, add 0.5 mL of boil-inactivated diluted crude enzyme solution to the blank tube, shake thoroughly, and then immediately add 1.5 mL of DNS reagent to each test tube. Boil in a water bath for 10 min, remove and cool to room temperature, add 10 mL of distilled water, shake well, and let stand. Measure the absorbance at 540 nm using a UV spectrophotometer. Then, determine the reducing sugar content according to the glucose standard curve, and subsequently calculate the carboxymethyl cellulase activity.
[0051] The glucose curves were obtained as follows: Dry, clean test tubes were numbered 0-8. Different volumes of distilled water and glucose standard solution were added to each tube to obtain glucose solutions of different concentration gradients. Then, 1.5 mL of DNS reagent was added, and the solutions were thoroughly mixed and boiled in a water bath for 10 min. After cooling to room temperature, 10 mL of distilled water was added to each tube. After mixing, the optical density of each solution was measured using a UV spectrophotometer at 540 nm. The glucose content (mg) was plotted on the x-axis for each group. Using the values as the ordinate, a glucose standard curve is plotted.
[0052] The results are as follows Figure 3 As shown, the equation for the glucose standard curve is: The carboxymethyl cellulase activity of the compound bacteria DF was calculated from day 1 to day 7 of growth. The enzyme activity showed a trend of first increasing and then decreasing with increasing culture time, and the maximum enzyme activity of 40.25 U·mL was observed on day 4 of culture. -1 The optimal enzyme production time for the compound bacteria DF is on day 4 of fermentation, at which point the carboxymethyl cellulase activity is at its maximum. This indicates that the compound bacteria has the ability to produce cellulase to degrade cellulose.
[0053] (8) Pot test to verify the degradation effect of compound bacteria DF on corn straw: Prepare compound bacteria suspension (1×10 8 cfu·mL -1 Using an equal volume of sterile water as a blank control and two commercial decomposition accelerators as controls, the straw was sprayed evenly on the surface of treated straw segments (3-5 cm) at a volume ratio of 1:1. The straw segments were then placed in small nylon mesh bags and placed in rectangular flowerpots (49 cm × 18 cm), covered with 2-3 cm of soil. Each pot contained 3.0 kg of sterile soil, and five straw bags (each containing 10.0 g of corn straw) were placed parallel to each other. The process was repeated three times, maintaining soil moisture at 60%-80% and an ambient temperature of 22-25℃. The straw bags were left to stand for 45 days. On days 5, 15, 25, 35, and 45, the straw bags were removed, and the soil and humus on the surface of the straw were washed with sterile water. The straw was then dried at 85℃ to constant weight, and the straw degradation rate was calculated.
[0054] The results are as follows Figure 4 , Figure 5 As shown, the degradation rate of corn straw under the treatment of compound bacteria DF increased with the increase of degradation time. After 45 days of degradation, the degradation rate reached the highest level of 43.40%, which was higher than that of commercial accelerators CF1 and CF2, and 3.2 times that of the water group CK.
[0055] (9) Scanning electron microscopy (SEM) verification test of the degradation effect of compound bacteria DF on corn straw: The treated dried potted straw samples were cut into appropriate sizes, fixed and sprayed with gold for 30s, and the micro-morphology of the surface structure of corn straw was observed using a scanning electron microscope under vacuum conditions.
[0056] The results are as follows Figures 6 to 9 As shown, the surface damage of the straw, from highest to lowest, is: DF > CF2 > CF1 > CK. The corn straw surface of the water-treated group CK is smooth and uniform, with a clearly visible coating, and the straw surface is relatively intact. However, the straw structure is severely damaged after degradation by the microbial agent and the compound microbial agent DF. The straw treated with DF shows more obvious decomposition pores and a higher degree of decay. Therefore, compared with single-strain bacteria and commercial microbial agents, the compound microbial agent DF has superior corn straw degradation ability. The microscopic morphological changes of the straw in potted plants after 45 days of degradation are obvious under an electron microscope. The straw structure after degradation by the compound microbial agent DF is severely damaged, with obvious decomposition pores and a high degree of decay. The compound degrading microbial agent DF in this embodiment is environmentally friendly, efficient, and non-toxic, showing good application prospects in the utilization of agricultural waste.
[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.
Claims
1. A highly efficient corn straw composite degrading bacteria DF, characterized in that: The aforementioned compound degrading bacteria DF is composed of Bacillus belesiensis (B. belesiensis) Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens HW-130; The aforementioned Bacillus belesii ( Bacillus velezensis HW-124 has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC NO.7.626 and deposit date of December 3, 2025. The aforementioned Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens HW-130 has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC NO.7.625 and deposit date of December 3, 2025.
2. The high-efficiency corn straw composite degrading bacteria DF according to claim 1, characterized in that: The aforementioned Bacillus belesii ( Bacillus velezensis HW-124 and Bacillus amyloliquefaciens ( Bacillus Amyloliquefaciens The composite ratio of HW-130 is 1:
1.
3. The application of the composite degrading bacteria DF according to any one of claims 1-2 in the degradation of crop straw.
4. The application of the composite degrading bacteria DF according to claim 3 in the degradation of crop straw, characterized in that: The crops mentioned include corn, rice, wheat, potatoes, and sorghum.