Bacillus subtilis MJ-4 fungicide and application thereof in prevention and control of cockroaches

Abstract

The invention discloses a bacillus subtilis MJ-4 microbial inoculum and application thereof in prevention and control of cockroaches, and the microbial inoculum is bacillus subtilis MJ-4 fermentation liquor obtained by taking bacillus subtilis MJ-4 as a strain and performing seed activation and fermentation. According to the invention, the bacillus subtilis MJ-4 with insecticidal broad spectrum is used as a biocontrol bacterium to prevent and control the ravoc of cockroaches, aiming at the problems in the existing prevention and control, the cockroaches are prevented and controlled to generate drug resistance, and the environment-friendly, non-toxic and harmless biological prevention and control are realized; the strain MJ-4 is environment-friendly, can be combined with baits, can well attract cockroaches to eat, has a remarkable killing effect, has no adverse effect on vertebrates, and can be developed and utilized as a good biological control fungicide due to the fact that bacterial powder is easy to produce and low in cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of biological control, and relates to a bacillus subtilis MJ-4 microbial agent and application thereof in preventing and controlling cockroaches. BACKGROUND

[0002] Cockroaches belong to Blattodea insects, and are dark and light-averse, nocturnal and omnivorous, widely distributed in China, and like to live in warm, humid, food-rich and multi-gap places. The main hazards of cockroaches are the spread of diseases, the induction of allergic reactions, the damage of food and articles, the psychological harm and the destruction of environmental health, etc. The bacteria carried by cockroaches include Salmonella, Escherichia coli and Staphylococcus, which can cause food poisoning, diarrhea and other diseases; the excrement, dander and saliva of cockroaches can cause allergic reactions in human body, such as asthma and urticaria, which are serious hazards to human living environment and health.

[0003] At present, the cockroach control methods on the market mainly rely on chemical insecticides. These insecticides usually kill cockroaches through contact, food or fumigation. However, these insecticides have potential hazards to the environment and human body. First of all, the use of chemical insecticides can cause environmental pollution, especially to water sources and soil. Secondly, chemical insecticides also have potential hazards to human body. Long-term contact with chemical insecticides can cause various health problems, including skin and eye irritation, respiratory problems, nervous system problems and reproductive system problems, etc. In addition, cockroaches may also develop resistance to chemical insecticides, making the effect of chemical insecticides gradually weaken. Biological control method is a method of using natural enemies, pathogens or other biological factors to control pests, which can effectively control pests and reduce the harm to the environment and human body. Therefore, it is necessary to develop an environmentally friendly and harmless biological control method. SUMMARY

[0004] The present application aims to provide a bacillus subtilis MJ-4 microbial agent and application thereof in preventing and controlling cockroaches, so as to solve the technical problem of poor effect of existing cockroach control measures.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions. In a first aspect, the present application provides a bacillus subtilis MJ-4 microbial agent, which is a bacillus subtilis MJ-4 fermentation broth obtained by using bacillus subtilis MJ-4 as a microbial strain and through seed activation and fermentation.

[0006] According to a preferred embodiment, the effective viable cell count of the bacillus subtilis MJ-4 fermentation broth is 1x10 8 ~1x10 11 CFU / mL.

[0007] The second aspect is the application of the bacillus subtilis MJ-4 agent in the product for preventing and controlling cockroaches.

[0008] The bacillus provided by the application is bacillus subtilis (Bacillus subtilis) Bacillus subtilis ) MJ-4, and the preservation number is CGMCC No. 30850. The strain is stored in the China General Microbiological Culture Collection Center, and the preservation date is June 3, 2024, and the state is alive.

[0009] The application has the following beneficial effects: 1. The strain MJ-4 is environmentally friendly, can attract cockroaches to eat when combined with bait, has no adverse effects on vertebrates, and is simple and low-cost in production, so it can be developed and utilized as a good biological control agent. 2. The strain MJ-4 has good contact and stomach poison insecticidal activity on nymphs and male and female adult cockroaches, and can produce a killing effect on cockroaches in a short period of time. Compared with chemical agents on the market, it has better virulence and is not easy to produce drug resistance to cockroaches, and the mortality rate can reach 100%. 3. The application uses a bacillus subtilis (Bacillus subtilis) Bacillus subtilis ) MJ-4 with broad-spectrum insecticidal activity as a biocontrol bacterium to prevent and control cockroaches, and solves the problem of drug resistance of cockroaches in the existing prevention and control, and achieves environmental protection, non-toxic and harmless biological control. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 The contact killing mortality of different concentrations of MJ-4 bacterial liquid on cockroaches; Figure 2 The stomach poison mortality of different concentrations of MJ-4 bacterial powder on cockroaches; Figure 3 The contact killing mortality of the srfAA knockout mutant on dubia cockroaches is counted; Figure 4 The anatomic diagram of each organ of the control cockroaches and the dead cockroaches feeding on the bacterial powder; Figure 5 The anatomic diagram of the rectal pad and the Malpighian tubule of the control cockroaches and the dead cockroaches feeding on the bacterial powder; Figure 6 The section diagram of the invasion of the MJ-4-GFP marked strain into the gastric caecum and fat body; Figure 7 The sequence phylogenetic tree of 16S rDNA, gyrB and rpoB of the MJ-4 strain. DETAILED DESCRIPTION

[0011] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0012] A Bacillus subtilis MJ-4 inoculant, the inoculant being a Bacillus subtilis MJ-4 inoculum obtained through seed activation and fermentation to produce a Bacillus subtilis MJ-4 fermentation broth.

[0013] A Bacillus subtilis MJ-4 inoculant, wherein the inoculant is a Bacillus subtilis MJ-4 powder, paste, granules, emulsion or suspension obtained from the fermentation broth of Bacillus subtilis MJ-4.

[0014] The effective viable count of Bacillus subtilis MJ-4 fermentation broth is 1×10⁻⁶. 8 ~1×10 11 CFU / mL.

[0015] The 16S rDNA sequence of Bacillus subtilis MJ-4 is shown in SEQ ID NO. 1.

[0016] Application of Bacillus subtilis MJ-4 in cockroach control products.

[0017] The application of Bacillus subtilis MJ-4 in the biological control of cockroaches demonstrates that this strain exhibits contact and stomach poison insecticidal activity against all stages of cockroach development.

[0018] The classification and nomenclature of Bacillus provided by this invention is Bacillus subtilis (Bacillus subtilis) Bacillus subtilis MJ-4, with accession number CGMCC No. 30850, is deposited at the China General Microbiological Culture Collection Center on June 3, 2024, and is in viable condition.

[0019] Example 1 Bacillus subtilis ( Bacillus subtilis MJ-4 screening.

[0020] I. Screening Process This invention relates to the diseased and dead coleopteran insect, the bark beetle (*Pinus tabuliformis*), which cuts the branches of pine trees in horizontal pits. Blastophagus minorA few suspected pathogenic bacteria were isolated in vivo and in the environment, and after streak culture purification and culture in LB liquid medium, the above strain MJ-4 was gradually screened out after being inoculated into healthy bark beetles one by one, and the strain MJ-4 with the strongest virulence was inoculated into cockroaches, and the cockroaches also had strong pathogenicity. The strain MJ-4 was successfully isolated from the dead cockroaches, and was inoculated into healthy cockroaches again, and still had pathogenicity, so the strain MJ-4 was determined to be the pathogenic bacteria of the cockroaches.

[0021] II. Colony morphological characteristics and identification The most suitable temperature for growth of the strain MJ-4 is 37 DEG C. On the LB plate medium, the colony is light yellow, the color is positive and negative without difference, slightly transparent, the surface is rough and lusterless, the edge is round or oval, the colony has pentagonal or irregular small protrusions, the surface is dry and presents wrinkles, the bacterial body is viscous and moist and easy to pick up, the distribution is small and uniform, and has a smell. The three pairs of primers are used for PCR amplification respectively, and the gene sequences are 1028 bp, 16s rDNA 、 gyrB 、 rpoB The three pairs of primers are used for PCR amplification respectively, and the gene sequences are 1028 bp, 16s rDNA 1348 bp, gyrB and 764 bp. The BLAST comparison result of the multi-primers on the NCBI website shows that the similarity of the strain MJ-4 and Bacillus subtilis is higher than 99.9%. After determining the three pairs of gene sequences of the isolated strain MJ-4, the morphological identification is combined to determine that the isolated strain is Bacillus subtilis (Bacillus subtilis) MJ-4. rpoB 、 16s rDNA 、 gyrB 、 rpoB Bacillus subtilis ) MJ-4.

[0022] Example 2 Touching and stomach poison virulence determination of Bacillus subtilis (Bacillus subtilis) MJ-4 on cockroaches. Bacillus subtilis

[0023] I. Touching: the Bacillus subtilis MJ-4 bacterial powder was weighed and dissolved in water, and the bacterial liquid concentration was adjusted to 1x10 10 CFU / mL, 1x10 9 CFU / mL and 1x10 8 ​​CFU / mL three concentrations, 2-3 drops of Tween 20 surfactant was added to the bacterial liquid for standby. Secondly, take healthy individuals of cockroaches, cockroaches are common indoor cockroaches in southern China, 15 in each group, and the bacterial liquid of each concentration is sprayed evenly on the back of the cockroaches with a spray bottle until the back is wet. The mortality rate of cockroaches was counted after 24 h, and the observation was continuously counted to the 6th day. The experimental data was analyzed for significance by software SPSS, and each group was repeated 3 times. The contact killing mortality rate of Bacillus subtilis MJ-4 bacterial liquid on cockroaches is shown in detail in Table 1. Figure 1 .

[0024] Secondly, the stomach poison: take Bacillus subtilis MJ-4 bacterial powder and mix it with corn flour. Adjust the concentration of the mixed bacterial powder to 1×10 10 CFU / g, 1×10 9 CFU / g, 1×10 8 CFU / g three gradients, and place the mixed bacterial powder in the container for feeding the cockroaches. Starve the cockroaches for 24 h before feeding. Observe the reaction of the cockroaches after they eat the bacterial powder. The cockroaches do not eat, spit out mucus from the mouth, move slowly, and other phenomena. Start to die after 24 h, and lose physiological response. The stomach poison mortality rate of Bacillus subtilis MJ-4 bacterial powder on cockroaches is shown in detail in Table 2. Figure 2 、 Figure 3 .

[0025] The contact killing results show that the treatment with a bacterial liquid concentration of 1×10 10 CFU / mL, the cockroaches died successively on the first day, reaching 100% mortality rate. The treatment with a concentration of 1×10 9 CFU / mL, the mortality rate of cockroaches was 43.25% on the first day, and reached 67.81% on the 6th day. The treatment with a concentration of 1×10 8 CFU / mL, the mortality rate of cockroaches was 9.19% on the first day, and reached 27.58% on the 6th day. The mortality rate of the control group was 2.96% on the 6th day.

[0026] Experimental observation: after the cockroaches in each treatment contacted the bacterial liquid, they began to react violently, did not eat, and the cockroaches in the high concentration treatment turned their bellies, their bodies were stiff, and gradually lost physiological response. After 24 h, the dead cockroaches in each group showed symptoms of darkening of the body color.

[0027] After the cockroaches that died from eating the bacteria powder were dissected, it was found that the rectal pads and the Malpighian tubules of the digestive organs showed obvious blackening and lesions compared with the healthy organs of the control cockroaches. The PHT01-P43-GFP-mut3a fluorescent plasmid was transformed into Bacillus subtilis MJ-4 by natural transformation to obtain a Bacillus subtilis MJ-4-GFPmut3a fluorescent mutant strain. After the cockroaches ate the fluorescent bacteria, they also showed a state of death. The fluorescent signal in the tissues of the organs of the corpse was detected by making a section. Green fluorescent signals were found in the fat body and gastric caecum.

[0028] The stomach poison results show that: in the treatment with a bacteria powder concentration of 1×10 10 CFU / g, the cockroaches died successively on the first day, and the mortality rate reached 52.72%. On the second day, the mortality rate reached 100%. In the treatment with a concentration of 1×10 9 CFU / g, the mortality rate of the cockroaches was 40% on the first day, and reached 91% on the sixth day. In the treatment with a concentration of 1×10 8 CFU / g, the mortality rate of the cockroaches was 22% on the first day, and reached 86% on the sixth day. The mortality rate of the control group was 3.15% on the sixth day.

[0029] The surfactin knockout mutant Bacillus subtilis MJ-4- ΔsrfAA was used to kill cockroaches. 9 The concentration was set to 1×10 ΔsrfAA CFU / mL. The mortality rate of the cockroaches killed by the surfactin knockout mutant Bacillus subtilis MJ-4- was 17.29% on the sixth day, while the mortality rate of the cockroaches killed by the wild type MJ-4 was 67.81%, and the mortality rate of the control was 2.96%. This shows that surfactin is a key factor in killing insects when the cockroaches are touched.

[0030] Example 3 Killing effect of Bacillus subtilis (B. Bacillus subtilis ) MJ-4 on cockroaches in a closed environment.

[0031] Bacillus subtilis (B. Bacillus subtilis ) MJ-4 bacteria powder was mixed with brown sugar at a ratio of 1:9 to become a bacterial agent. The concentration of the Bacillus subtilis (B. Bacillus subtilis ) MJ-4 bacteria powder was 1×10 11CFU / g, 3 copies of about 30 grams were respectively placed in 3 100 square meter laboratories in Wuhua District of Kunming City, and placed in the corner or hidden place. After putting in, the number of dead cockroaches in the room was investigated every 3 days, and the specific results are shown in Table 1. The results show that after the bacterial agent is put in, dead cockroaches can be seen in the three spaces, and with the passage of time, the number of dead cockroaches is more and more, to the 6th day, the average number of dead cockroaches reaches 152; on the 7th day, the average number of dead cockroaches reaches 163; on the 8th day, the average number of dead cockroaches reaches 172.7; on the 9th day and the 10th day, the average number of dead cockroaches reaches 173, and thereafter, no new dead cockroaches are seen in the space, and no live cockroaches are seen, that is, the cockroaches may be completely eliminated.

[0032] Table 1, results of killing cockroaches by Bacillus subtilis MJ-4 preparation

[0033] Example 4 Effect of Bacillus subtilis (MJ-4) on other pests. Bacillus subtilis

[0034] The Bacillus subtilis MJ-4 described in the present application has a broad-spectrum insecticidal effect on various pests. Through experiments, it can be obtained that the bacteria have strong insecticidal activity on cockroaches, and the bacteria also have certain insecticidal pathogenic ability on pests such as Coleoptera, Lepidoptera and Blattaria. It has selectivity to vertebrates and natural enemy insects such as mice, predatory mites and parasitic bees, is harmless to plants, and is environmentally friendly. Table 2 is the determination of the control effect of MJ-4 on the pine bark beetle.

[0035] Table 2, determination of the control effect of Bacillus subtilis MJ-4 on the pine bark beetle

[0036] Bacillus subtilis (MJ-4) identification sequence number (MJ-4) Bacillus subtilis 16S , rpoB , gyrB three pairs of primers.

[0037] 16S rDNA GGGGGTGCTA TAATGCAAGT CGAGCGGACA GATGGGAGCT TGCTCCCTGA TGTTAGCGGC 60 GGACGGGTGA GTAACACGTG GGTAACCTGC CTGTAAGACT GGGATAACTC CGGGAAACCG 120 ​​GGGCTAATAC CGGATGGTTG TTTGAACCGC ATGGTTCAAA CATAAAAGGT GGCTTCGGCT 180 ACCACTTACA GATGGACCCG CGGCGCATTA GCTAGTTGGT GAGGTAACGG CTCACCAAGG 240 CAACGATGCG TAGCCGACCT GAGAGGGTGA TCGGCCACAC TGGGACTGAG ACACGGCCCA 300 GACTCCTACG GGAGGCAGCA GTAGGGAATC TTCCGCAATG GACGAAAGTC TGACGGAGCA 360 ACGCCGCGTG AGTGATGAAG GTTTTCGGAT CGTAAAGCTC TGTTGTTAGG GAAGAACAAG 420 TACCGTTCGA ATAGGGCGGT ACCTTGACGG TACCTAACCA GAAAGCCACG GCTAACTACG 480 TGCCAGCAGC CGCGGTAATA CGTAGGTGGC AAGCGTTGTC CGGAATTATT GGGCGTAAAG 540 GGCTCGCAGG CGGTTTCTTA AGTCTGATGT GAAAGCCCCC GGCTCAACCG GGGAGGGTCA 600 TTGGAAACTG GGGAACTTGA GTGCAGAAGA GGAGAGTGGA ATTCCACGTG TAGCGGTGAA 660 ATGCGTAGAG ATGTGGAGGA ACACCAGTGG CGAAGGCGAC TCTCTGGTCT GTAACTGACG 720 CTGAGGAGCG AAAGCGTGGG GAGCGAACAG GATTAGATAC CCTGGTAGTC CACGCCGTAA 780 ACGATGAGTG CTAAGTGTTA GGGGGTTTCC GCCCCTTAGT GCTGCAGCTA ACGCATTAAG 840 CACTCCGCCT GGGGAGTACG GTCGCAAGAC TGAAACTCAA AGGAATTGAC GGGGGCCCGC 900 ACAAGCGGTG GAGCATGTGG TTTAATTCGA AGCAACGCGA AGAACCTTAC CAGGTCTTGA CATCCTCTGA ACATCCTAGA PRICECGT CCCCTTCGGG GCAAAATGAC AGGTGGTGCA1020 TGGTTGCC 1028

[0038] rpoB TTCCGCGCGA GCTATGCTCG CATTAGCGAA GTGTTAGAAT TACCAAATCT CATTGAAATT CAAACCTCTT CTTATCAGTG GTTTCTTGAT GAGGGTCTTA GAGAGATGTT TCAAGACATA 120 TCACCAATTG AGGATTTCAC TGGTAACCTC TCTCTTGAGT TCATTGATTA TAGTTTAGGT 180 240. GAGCCTAAAT ATCCTGTAGA GGAATCAAAA GAACGTGATG TGACTTACTC AGCTCCGCTA AGAGTGAAGG TTCGTTTAAT TAACAAAGAA ACTGGAGAGG TAAAAGACCA AGATGTCTTC ATGGGTGATT TCCCTATTAT GACAGATACA GGTACTTTTA TCATTAACGG TGCGGAACGT 360 GTTATTGTTT CCCAGCTGT TCGGTCTCCA AGTGTATATT TCAGTGGTAA OWNER 420 AACGGTAAAA AAGGTTTTAC CGCAACTGTC ATTCCAAACC GTGGCGCATG GTTAGAATAC 480 GAAACTGATG CGAAAGATGT TGTTTATGTC CGCATTGATC GCACACGTAA GTTGCCGGTT 540 ACGGTTCTTT TGCGTGCTCT CGGCTTCGGC TCCGATCAAG AGATTCTTGA TCTCATAGGA 600 GAAAACGAAT ACCTGCGAAA TACGCTTGAT AAAGATAACA CAGAAAACAG TGACAAAGCG 660 TTGCTGGAAA TTTACGAGCG TCTCCGTCCT GGAGAGCCGC CTACAGTAGA AAATGCGAAA 720 AGCTTGCTTG ATTCTCGTTT CTTTGATCCG AACGATCGAT GCCC 764

[0039] gyrB ATGGAACAGC AGCAAAACAG TTATGATGAA AATCAGATAC AGGTACTAGA AGGATTGGAA 60 GCTGTTCGTA AAAGACCGGG GATGTATATC GGTTCGACAA ACAGCAAAGG CCTTCACCAC 120 CTGGTATGGG AAATTGTCGA CAATAGTATT GACGAAGCCC TCGCCGGTTA TTGTACGGAT 180 ATCAATATCC AAATCGAAAA AGACAACAGT ATCACGGTTG TAGATAATGG CCGCGGTATT 240 CCAGTCGGTA TTCATGAAAA AATGGGCCGT CCTGCGGTAG AAGTCATTAT GACGGTACTT 300 CATGCCGGAG GAAAATTTGA CGGAAGCGGC TATAAAGTAT CCGGAGGATT ACACGGTGTA 360 GGTGCGTCTG TCGTAAACGC ACTATCAACA GAGCTTGATG TGACGGTTCA CCGTGACGGT 420 AAAATTCACC GCCAAACTTA TAAACGCGGA GTTCCGGTTA CAGACCTTGA AATCATTGGC 480 GAAACGGATC ATACAGGAAC GACGACACAT TTTGTCCCGG ACCCTGAAAT TTTCTCAGAA 540 ACAACCGAGT ATGATTATGA TCTGCTTGCC AACCGCGTAC GTGAATTAGC CTTTTTAACA 600 AAGGGCGTAA ACATCACGAT TGAGGATAAA CGTGAAGGAC AAGAGCGCAA AAATGAATAC 660 CATTACGAAG GCGGAATTAA AAGTTATGTA GAGTATTTAA ACCGCTCTAA AGAGGTTGTC 720 CATGAAGAGC CGATTTACAT TGAAGGCGAA AAGGACGGCA TTACGGTTGA AGTGGCTTTG 780 CAATACAATG ACAGCTACAC AAGCAACATT TACTCGTTTA CAAACAACAT TAACACGTAC 840 GAAGGCGGTA CCCATGAAGC TGGCTTCAAA ACGGGCCTGA CTCGTGTTAT CAACGATTAC 900 GCCAGAAAAA AAGGGCTTAT TAAAGAAAAT GATCCAAACC TAAGCGGAGA TGACGTAAGG 960 GAAGGGCTGA CAGCGATTAT TTCAATCAAA CACCCTGATC CGCAGTTTGA GGGCCAAACG1020 AAAACAAAGC TGGGCAACTC AGAAGCACGG ACGATCACCG ATACGTTATT TTCTACGGCG1080 ATGGAAACAT TTATGCTGGA AAATCCAGAT GCAGCCAAAA AAATTGTCGA TAAAGGCTTA1140 ATGGCGGCAA GAGCAAGAAT GGCTGCGAAA AAAGCCCGTG AACTAACACG TCGTAAGAGT 1200 GCTTTGGAAA TTTCAAACCT GCCCGGTAAG TTAGCGGACT GCTCTTCAAA AGATCCGAGC 1260 ATCTCCGAGT TATATATCGT AGAGGGTGAC TCTGCCGGAG GATCTGCTAA ACAAGGACGC 1320 GACAGACATT TCCAAGCCAT TTTGCCGCTT AGAGGTAAAA TCCTAAACGT TGAAAAGGCC 1380 AGACTGGATA AAATCCTTTC TAACAACGAA GTTCGCTCTA TGATCACAGC GCTCGGCACA 1440 GGTATTGGGG AAGACTTCAA CCTTGAGAAA GCCCGTTACC ACAAAGTTGT CATTATGACA 1500 GATGCCGATG TTGACGGCGC GCACATCAGA ACACTGCTGT TAACGTTCTT TTACAGATAT 1560 ATGCGCCAAA TTATCGAGAA TGGCTACGTG TACATTGCGC AGCCGCCGCT CTACAAGGTT 1620 CAACAGGGGA AACGCGTTGA ATATGCGTAC AATGACAAGG AGCTTGAAGA GCTGTTAAAA 1680 ACTCTTCCTC AAACCCCTAA GCCTGGACTG CAGCGTTACA AAGGTCTTGG TGAAATGAAT 1740 GCCACCCAGC TATGGGAGAC AACCATGGAT CCTAGCTCCA GAACACTTCT TCAGGTAACT 1800 CTTGAAGATG CAATGGATGC GGACGAGACT TTTGAAATGC TTATGGGCGA CAAGGTAGAA 1860 CCGCGCCGAA ACTTCATAGA AGCGAATGCG AGATACGTTA AAAATCTTGA CATCTAA 1917

Claims

1. A Bacillus subtilis MJ-4 inoculant, characterized in that: The inoculant is a Bacillus subtilis MJ-4 fermentation broth obtained through seed activation and fermentation.

2. The Bacillus subtilis MJ-4 inoculant according to claim 1, characterized in that: The bacterial agent is a powder, paste, granule, emulsion or suspension of Bacillus subtilis MJ-4 obtained from the fermentation broth of Bacillus subtilis MJ-4.

3. The Bacillus subtilis MJ-4 inoculant according to claim 1, characterized in that: The effective viable count in the Bacillus subtilis MJ-4 fermentation broth was 1×10⁻⁶. 8 ~1×10 11 CFU / mL.

4. The Bacillus subtilis MJ-4 according to claim 1, characterized in that: The 16S rDNA sequence of Bacillus subtilis MJ-4 is shown in SEQ ID NO.

1.

5. The application of Bacillus subtilis MJ-4 according to any one of claims 1 to 4 in products for cockroach control.

6. The application of Bacillus subtilis MJ-4 according to claim 5 in the biological control of cockroaches, characterized in that: This strain exhibits both contact and stomach poison insecticidal activity against all stages of cockroach development.

Images