CN112646008B - Application of Elicitin-like gene and its expression vector inducing HR in Pythium ultimum - Google Patents

Abstract

The invention belongs to the technical field of genetic engineering, and discloses an Elicitin gene for inducing HR in pythium ultimum and application of an expression vector thereof. The invention identifies three Elicitin genes PYOD6, PYOD7 and PYOD20 from Pythium ultimum, wherein the nucleotide sequences of the PYOD6, the PYOD7 and the PYOD20 genes are respectively shown in SEQ ID NO. 1-3 in sequence. According to the invention, three Elicitin genes identified from Pythium ultimum can generate obvious HR reaction to stimulate plant immunity.

Description

Application of Elicitin-like gene and its expression vector inducing HR in Pythium ultimum

technical field

The present invention belongs to the technical field of genetic engineering, and specifically relates to an Elicitin gene for inducing HR in Pythium ultimum and the application of its expression vector.

Background technique

During the long-term co-evolution of plants and pathogens, pathogens have evolved a large number of weapons to attack their hosts, such as effectors, in order to infect plants better. Pathogens secrete these effector proteins into plants in order to promote their better infection of host plants. However, along with the co-evolution of plants, some effector proteins will be recognized by genes that regulate disease resistance in the plant's own evolution. Recognition of pathogens often triggers a localized resistance response, known as hypersensitivity (HR), characterized by rapid cell death at the site of infection. For the study of plant-pathogen interactions, this apparent HR response is also an important signal to stimulate plant immunity.

Pythium ultimum is a pathogen that can widely infect soybeans, kidney beans, peas, sweet potatoes, pine seedlings, coffee, apples, citrus, peach, cotton, chrysanthemum, dahlia, pumpkin, watermelon, sugarcane, alfalfa, tomato, etc. More than 150 kinds of economic plants cause various diseases such as seedling wither, damping off, root rot, foot rot, and blight. We obtained three genes from Pythium ultimum that can trigger plant hypersensitivity response (HR) through extensive screening. All three genes contain Elicitin domains and are typical immune elicitors. Stimulating HR, triggering plant immunity, inducing plants to produce disease resistance responses, is helpful for research and development of plant resistance inducers. The powerful functions of these three genes can be used as candidate genes for the development of plant inducers.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an Elicitin gene and its expression vector for inducing HR in Pythium ultimum. The three immune elicitor genes identified in the present invention can be used as theoretical knowledge supplements for developing immune inducers, and provide theoretical guidance for preventing and controlling crop diseases and insect pests.

The object of the present invention can be realized through the following technical solutions:

The present invention identifies three Elicitin genes PYOD6, PYOD7 and PYOD20 from Pythium ultimum, and the nucleotide sequences of the PYOD6, PYOD7 and PYOD20 genes are shown in SEQ ID NO.1-3 respectively. The proteins encoded by the three Elicitin genes are PYOD6, PYOD7 and PYOD20, and their amino acid sequences are shown in SEQ ID NO.4-6 respectively.

The expression cassette, recombinant expression vector, transgenic cell line or transgenic recombinant bacteria containing the above-mentioned Elicitin gene.

The recombinant expression vectors PBIN-PLUS:PYOD6, PBIN-PLUS:PYOD7 and PBIN-PLUS:PYOD20 containing the above-mentioned Elicitin-like genes.

The recombinant expression vectors PBIN-PLUS:PYOD6, PBIN-PLUS:PYOD7 and PBIN-PLUS:PYOD20 of the Elicitin-like genes PYOD6, PYOD7 and PYOD20 genes were constructed. Using the plant expression vector PBIN-PLUS as the starting vector, the PYOD6, PYOD7 and PYOD20 genes were respectively inserted into the Sma1 restriction site of PBIN-PLUS to obtain.

The Elicitin gene and its expression vector can stimulate the immune response of plants, provide a knowledge base for the development of immune inducers, and provide theoretical guidance for the prevention and control of crop diseases and insect pests.

A plant immune inducer, which contains the above-mentioned Pythium ultimum immune-inducing protein or the fermentation broth of the above-mentioned Pythium ultimum immune-inducing protein.

Use of the above Elicitin gene, the above protein or the above recombinant expression vector in inducing plant necrosis.

Application of the above-mentioned Elicitin gene, the above-mentioned protein or the above-mentioned recombinant expression vector in the development of a plant immune inducer.

The application of the above Elicitin gene in breeding disease-resistant crop varieties.

In a method for stimulating plant immunity, the above-mentioned Elicitin gene or recombinant expression vector is introduced into plants, which can stimulate plant immune response and improve plant resistance. It is also a method for constructing disease-resistant varieties. The above-mentioned gene or recombinant expression vector is introduced into crop plants, and positive transformed plants are obtained through resistance screening to obtain disease-resistant crop varieties.

Beneficial effects of the present invention:

The present invention identifies three Elicitin genes from Pythium ultimum, and inserts them into the expression vector PBIN-PLUS. Introducing the vector into plants can generate a significant HR response and stimulate plant immunity. The three PYOD6, PYOD7 and PYOD20 genes can be used as potential candidates for the development of plant immune inducers, which provide theoretical support for the prevention and control of plant diseases.

Description of drawings

Figure 1 is a phenotypic map and a bar chart of quantitative calibration of HR degree of PYOD6, PYOD7 and PYOD20 genes inducing HR in plants.

Among them, A is the phenotype diagram of the significant effect of inducing plant HR, the left one is the negative control GFP gene treatment, the second left is the positive control INF1 gene treatment, and the three right three are the three gene treatments of PYOD6, PYOD7, PYOD20; it can be clearly seen Three genes PYOD6, PYOD7, PYOD20 were identified to stimulate HR response. B is the bar graph of quantitative calibration of HR degree, the number corresponding to Figure 1A, it can be clearly seen that the three genes stimulated the HR degree similar to that of the positive control, and significantly higher than that of the negative control (Student's t test: ****p <0.0001).

Detailed ways

The present invention will be described in detail below with reference to specific embodiments. From the following description and these Examples, one skilled in the art can ascertain the essential characteristics of this invention, and without departing from the spirit and scope of the invention, can make various changes and modifications of the invention to adapt it to various uses and conditions.

Example 1 Amplification and sequencing of three Elicitin-like genes

1. Experimental strains

The test strain, Pythium ultimum, was preserved in the 10% V8 solid medium by the Interaction Laboratory of Plant and Phytophthora, Department of Plant Diseases, Nanjing Agricultural University, and the preservation temperature was 10°C.

2. Preparation of N. benthamiana seedlings for testing

Nicotiana benthamiana was sown in plastic pots (d=10cm) filled with vermiculite (2-4mm) and grown in a 14h light (strong light)/10h dark greenhouse. Let it grow for 7 days, after growing two true leaves, transplant it to the vermiculite black soil and the culture soil with a volume ratio of 5:1 for 30 days, take the leaves of the same 3, 4, and 5 leaf positions for 30 days. For expression of experimental genes, and then continue to observe whether the leaf phenotype has obvious HR for 7 days.

3. Extract the RNA of Pythium ultimum and obtain the cDNA of the target gene

The ultimate Pythium hyphae were collected, then snap-frozen in liquid nitrogen and then put into a mortar for cooling and grinding. The ultimate Pythium total RNA extraction and purification was carried out with reference to the method recommended by the total RNA extraction and purification kit of Tiangen Company. Referring to the method provided by the RNA reverse transcription kit of Novozymes, cDNA was synthesized by reverse transcription with Oligo(dT) as the primer. Using the above cDNA as a template, PCR amplification was performed with the corresponding upstream and downstream primers (see Table 1 for primer sequences).

Table 1 Primer sequences

name sequence PBIN-PLUS-Sma1-PYOD6-F CGATAGGGTACCCCCATGTACACCAAGTTCGCC PBIN-PLUS-Sma1-PYOD6-R GGATCCGTCGACCCCGCAAGCTGGCTTGACGGT PBIN-PLUS-Sma1-PYOD7-F CGATAGGGTACCCCCATGTACACCAAGTTCGCC PBIN-PLUS-Sma1-PYOD7-R GGATCCGTCGACCCCGCAAGCTGGCTTGACGGT PBIN-PLUS-Sma1-PYOD20-F CGATAGGGTACCCCCATGAAGTTCCAAGCCGTC PBIN-PLUS-Sma1-PYOD20-R GGATCCGTCGACCCCGAAGCAGCTGCCCTCGAA

The PCR reaction system was: 2.5 μL 10× PCR reaction buffer; 1.5 μL 1.5 mM MgCl2; 0.5 μL 2.5 mM dNTPs; 0.25 μL Taq DNA polymerase (5.0 U/μL); 0.5 μL primer; 0.5 μL template; to 25 μL.

The reaction program was as follows: pre-denaturation at 94 °C for 5 min; denaturation at 94 °C for 15 s, annealing at 58 °C for 15 s, extension at 72 °C for 1:30 min, 35 cycles; extension at 72 °C for 10 min; storage at 4 °C.

The above PCR amplification products are subjected to agarose gel electrophoresis, recovered, and confirmed by sequencing, and the obtained sequences are the nucleotide sequences of the three Elicitin genes. The Elicitin gene includes three Elicitin genes PYOD6, PYOD7 and PYOD20 from Pythium ultimum respectively. The nucleotide sequences of the PYOD6, PYOD7 and PYOD20 genes are shown in SEQ ID NO.1-3 respectively. Show. The amino acid sequences of the proteins encoded by the three Elicitin genes are shown in SEQ ID NO. 4-6 respectively. Subsequent studies found that it has a powerful function of inducing plant necrosis and accumulation of reactive oxygen species.

Example 2 Construction of PBIN-PLUS:GFP, PBIN-PLUS:INF1, PBIN-PLUS:PYOD6, PBIN-PLUS:PYOD7 and PBIN-PLUS:PYOD20 expression vectors

The PBIN-PLUS (BIOVECTOR China Plasmid Vector Strain Cell Line Gene Collection Center) empty vector plasmid was digested with SmaI. The cDNA and the vector were ligated using Novozyme's homologous recombinase.

The reaction system is as follows: 2 μL of 10×CEII reaction buffer; 2 μL of the above-mentioned PCR product; 2 μL of the above digested empty vector; 1 μL of homologous recombinase; sterile water to make up to 10 μL.

The reaction procedure was as follows: 30 min at 37°C. The ligation product was transformed into Escherichia coli DH5α, and the transformants were screened on Kan resistance medium, and positive clones were picked to extract plasmids for colony PCR identification. The identified positive clones were sequenced, and the PBIN-PLUS:GFP, PBIN-PLUS:INF1, PBIN-PLUS:PYOD6, PBIN-PLUS:PYOD7 and PBIN-PLUS:PYOD20 expression vectors were obtained correctly.

Example 3 Transformation of Agrobacterium with expression vector and functional verification

1. Obtain Agrobacterium competent cells

Streak the Agrobacterium GV3101 strain on the LB solid medium plate, and invert at 28°C for 18-20h; place a single colony in LB liquid medium (containing 100mg/L Rif), and shake it at 28°C for 18-20 hours. 20h; 100 times the volume of bacterial liquid without antibiotics was added to the bacterial liquid, and the OD600 was shaken to 0.3-0.5 at 28 °C; after cooling on ice, centrifuge at 4000 r/min for 5 min at 4 °C, and discard the supernatant; add 20 mmol /L CaCl ₂ solution to suspend the precipitate, centrifuge at 4000 r/min for 5 min at 4°C, discard the supernatant; add 20 mmol/L CaCl ₂ solution to suspend the cell precipitate again for use.

2. PBIN-PLUS: GFP, PBIN-PLUS: INF1, PBIN-PLUS: PYOD6, PBIN-PLUS: PYOD7, PBIN-PLUS: PYOD20 expression vector to transform Agrobacterium

The PBIN-PLUS:GFP, PBIN-PLUS:INF1, PBIN-PLUS:PYOD6, PBIN-PLUS:PYOD7 and PBIN-PLUS:PYOD20 expression vectors were transformed into Agrobacterium cells by electroporation; the electroporation cup was washed three times with 70% alcohol, and then Air dry alcohol completely. 100ng of the expression vector was added to Agrobacterium-competent, and placed on ice for 30min. The Agrobacterium-competent cells were transferred into electroporation cups and electroporated at a voltage of 2.5 kV. After the electric shock was completed, Agrobacterium competent cells were added to 400 μL of LLB liquid medium, and cultured with shaking at 28° C. for 2 h. Pipette 20 μL of bacterial liquid, spread it evenly on a solid LB medium plate containing 50 mm kanamycin and 25 mm rifampicin, and invert at 28 °C for 48 h. Pick a single colony for colony PCR to obtain positive clones.

3. Transient expression of PBIN-PLUS:GFP, PBIN-PLUS:INF1, PBIN-PLUS:PYOD6, PBIN-PLUS:PYOD7 and PBIN-PLUS:PYOD20 proteins in N. benthamiana

The above-mentioned positive clones were placed in LB liquid medium and cultured with shaking at 28°C for 30h. The bacterial liquid was collected, centrifuged at 8000 rpm for 2 min, and washed three times with 10 mM MgCl 2 . Finally, the bacterial solution was diluted with 10 mM MgCl2 to an OD600 value of 0.3. The bacterial solution was mixed 1:1 with the bacterial solution containing the silencing inhibitor P19. All genes were injected on the tobacco leaves of this style with a 1mL syringe, with at least 5 replicates each, and the experiment was repeated three times. The results are shown in Figure 1.

PYOD6 gene

ATGTACACCAAGTTCGCCATCCTCGCCCTTGCCGCCTTCGCCGCTACGGCCGCCAACGC CGCGTCCACTGCTCCTTGCCCAAGCAGTGAACTCGCCAAGCTTGCTGGCTTGGCGTCGT CGCAGAACGTGTTCCCGTGCCAGGCCGTGTCGGGTGGTTTCAACATGATCCCACCATCG GGTCTGCCAACCACTGAGCAGCGCGCCAAGATGTGCGCGGCGCCAGTGTGCCACGCCC TGATCAAGGAAATCATCGCCCTCAACCCAACCGACTGCGTGCTCTCGCTCGGCAACTTG AACGTGAACGAACTCGCGAACGGCTTCGAGGCTTCATGCACGGCTTCGTCGCCAGCTC CAGCTGTGACCCCAGCGCCAGCGACTTCGGCTCCATCGACCCCATCCACGACGGCCCCT GGCACCCCATCCACGACGGCTCCATCGACCCCATCCACGACGGCGCCAGCCACCAACG GTACCCCAGCCCCAGCTGCCACCACCGTCAAGCCAGCTTGCTAA

PYOD7 gene

ATGTACACCAAGTTCGCCATCCTCGCCCTTGCCGCCTTCGCCGCTACGGCCGCCAACGC CGCGTCCACTGCTCCTTGCCCAAGCAGTGAACTCGCCAAGCTTGCTGGCTTGGCGTCGT CGCAGAACGTGTTCCCGTGCCAGGCCGTGTCGGGTGGTTTCAACATGATCCCACCATCG GGTCTGCCAACCACTGAGCAGCGCGCCAAGATGTGCGCGGCGCCAGTGTGCCACGCCC TGATCAAGGAAGTTGTCGCCCTCAACCCAACCGACTGCGTGCTCTCGATCGGCAACTTG AACGTGTACGAACTCGCGAACGGCTTCGAGGCTTCATGCACGGCTTCGTCGCCAGCTCC AGCTGTGACCCCAGCGCCAGCGACTTCGGCTCCATCGACCCCATCCACGACGGCCCCTG GCACCCCATCCACGACGGCGCCAGCCACCAACGGTACTCCAGCCCCAGCTGCCACCAC CGTCAAGCCAGCTTGCTAA

PYOD20 gene

ATGAAGTTCCAAGCCGTCCTCTTCGCCGCCGCTGCCGTCTTCGGCCTTGCCGCCGCCTAC GATGAAGTCACCGAGTGCCCAGCCACTGAATTCGTCAAGCTCGCGCCACTTGCGGCCA ACCCGAACTTGAACACCTGCCAAGCGGCATCGGAGGGCTGGCAGATGCTCCCACCAGT GGGTTACCCAACGGACACCCAGCGCGCTGCGATGTGCCTTGAGCCAACGTGCTTCAACT TGATCGACGCCATCAAGGCCCTGAACCCAAGCGACTGCATGTTGGTGTTTGGCGACGTC AAGTTGAACGTAAAGAAGCTCGCTGAAGAGTTCGAGGGCAGCTGCTTCTAA

PYOD6 protein

MYTKFAILALAAFAATAANAASTAPCPSSELAKLAGLASSQNVFPCQAVSGGFNMIPPSGLP TTEQRAKMCAAPVCHALIKEIIALNPTDCVLSLGNLNVNELANGFEASCTASSPAPAVTPAPATSAPSTPSTTAPGTPSTTAPSTPSTTAPATNGTPAPAATTVKPAC*

PYOD7 protein

MYTKFAILALAAFAATAANAASTAPCPSSELAKLAGLASSQNVFPCQAVSGGFNMIPPSGLP TTEQRAKMCAAPVCHALIKEVVALNPTDCVLSIGNLNVYELANGFEASCTASSPAPAVTPAPATSAPSTPSTTAPGTPSTTAPATNGTPAPAATTVKPAC*

PYOD20 protein

MKFQAVLFAAAAVFGLAAAYDEVTECPATEFVKLAPLAANPNLNTCQAASEGWQMLPPVG YPTDTQRAAMCLEPTCFNLIDAIKALNPSDCMLVFGDVKLNVKKLAEEFEGSCF*.

sequence listing

<110> Nanjing Agricultural University

<120> Application of Elicitin-like gene and its expression vector inducing HR in Pythium ultimum

<160> 6

<170> SIPOSequenceListing 1.0

<210> 1

<211> 513

<212> DNA

<213> Pythium ultimum

<400> 1

atgtacacca agttcgccat cctcgccctt gccgccttcg ccgctacggc cgccaacgcc 60

gcgtccactg ctccttgccc aagcagtgaa ctcgccaagc ttgctggctt ggcgtcgtcg 120

cagaacgtgt tcccgtgcca ggccgtgtcg ggtggtttca acatgatccc accatcgggt 180

ctgccaacca ctgagcagcg cgccaagatg tgcgcggcgc cagtgtgcca cgccctgatc 240

aaggaaatca tcgccctcaa cccaaccgac tgcgtgctct cgctcggcaa cttgaacgtg 300

aacgaactcg cgaacggctt cgaggcttca tgcacggctt cgtcgccagc tccagctgtg 360

accccagcgc cagcgacttc ggctccatcg accccatcca cgacggcccc tggcacccca 420

tccacgacgg ctccatcgac cccatccacg acggcgccag ccaccaacgg taccccagcc 480

ccagctgcca ccaccgtcaa gccagcttgc taa 513

<210> 2

<211> 489

<212> DNA

<213> Pythium ultimum

<400> 2

atgtacacca agttcgccat cctcgccctt gccgccttcg ccgctacggc cgccaacgcc 60

gcgtccactg ctccttgccc aagcagtgaa ctcgccaagc ttgctggctt ggcgtcgtcg 120

cagaacgtgt tcccgtgcca ggccgtgtcg ggtggtttca acatgatccc accatcgggt 180

ctgccaacca ctgagcagcg cgccaagatg tgcgcggcgc cagtgtgcca cgccctgatc 240

aaggaagttg tcgccctcaa cccaaccgac tgcgtgctct cgatcggcaa cttgaacgtg 300

tacgaactcg cgaacggctt cgaggcttca tgcacggctt cgtcgccagc tccagctgtg 360

accccagcgc cagcgacttc ggctccatcg accccatcca cgacggcccc tggcacccca 420

tccacgacgg cgccagccac caacggtact ccagccccag ctgccaccac cgtcaagcca 480

gcttgctaa 489

<210> 3

<211> 345

<212> DNA

<213> Pythium ultimum

<400> 3

atgaagttcc aagccgtcct cttcgccgcc gctgccgtct tcggccttgc cgccgcctac 60

gatgaagtca ccgagtgccc agccactgaa ttcgtcaagc tcgcgccact tgcggccaac 120

ccgaacttga acacctgcca agcggcatcg gagggctggc agatgctccc accagtgggt 180

tacccaacgg acacccagcg cgctgcgatg tgccttgagc caacgtgctt caacttgatc 240

gacgccatca aggccctgaa cccaagcgac tgcatgttgg tgtttggcga cgtcaagttg 300

aacgtaaaga agctcgctga agagttcgag ggcagctgct tctaa 345

<210> 4

<211> 170

<212> PRT

<213> Pythium ultimum

<400> 4

Met Tyr Thr Lys Phe Ala Ile Leu Ala Leu Ala Ala Phe Ala Ala Thr

1 5 10 15

Ala Ala Asn Ala Ala Ser Thr Ala Pro Cys Pro Ser Ser Glu Leu Ala

20 25 30

Lys Leu Ala Gly Leu Ala Ser Ser Gln Asn Val Phe Pro Cys Gln Ala

35 40 45

Val Ser Gly Gly Phe Asn Met Ile Pro Pro Ser Gly Leu Pro Thr Thr

50 55 60

Glu Gln Arg Ala Lys Met Cys Ala Ala Pro Val Cys His Ala Leu Ile

65 70 75 80

Lys Glu Ile Ile Ala Leu Asn Pro Thr Asp Cys Val Leu Ser Leu Gly

85 90 95

Asn Leu Asn Val Asn Glu Leu Ala Asn Gly Phe Glu Ala Ser Cys Thr

100 105 110

Ala Ser Ser Pro Ala Pro Ala Val Thr Pro Ala Pro Ala Thr Ser Ala

115 120 125

Pro Ser Thr Pro Ser Thr Thr Ala Pro Gly Thr Pro Ser Thr Thr Ala

130 135 140

Pro Ser Thr Pro Ser Thr Thr Ala Pro Ala Thr Asn Gly Thr Pro Ala

145 150 155 160

Pro Ala Ala Thr Thr Val Lys Pro Ala Cys

165 170

<210> 5

<211> 162

<212> PRT

<213> Pythium ultimum

<400> 5

Met Tyr Thr Lys Phe Ala Ile Leu Ala Leu Ala Ala Phe Ala Ala Thr

1 5 10 15

Ala Ala Asn Ala Ala Ser Thr Ala Pro Cys Pro Ser Ser Glu Leu Ala

20 25 30

Lys Leu Ala Gly Leu Ala Ser Ser Gln Asn Val Phe Pro Cys Gln Ala

35 40 45

Val Ser Gly Gly Phe Asn Met Ile Pro Pro Ser Gly Leu Pro Thr Thr

50 55 60

Glu Gln Arg Ala Lys Met Cys Ala Ala Pro Val Cys His Ala Leu Ile

65 70 75 80

Lys Glu Val Val Ala Leu Asn Pro Thr Asp Cys Val Leu Ser Ile Gly

85 90 95

Asn Leu Asn Val Tyr Glu Leu Ala Asn Gly Phe Glu Ala Ser Cys Thr

100 105 110

Ala Ser Ser Pro Ala Pro Ala Val Thr Pro Ala Pro Ala Thr Ser Ala

115 120 125

Pro Ser Thr Pro Ser Thr Thr Ala Pro Gly Thr Pro Ser Thr Thr Ala

130 135 140

Pro Ala Thr Asn Gly Thr Pro Ala Pro Ala Ala Thr Thr Val Lys Pro

145 150 155 160

Ala Cys

<210> 6

<211> 114

<212> PRT

<213> Pythium ultimum

<400> 6

Met Lys Phe Gln Ala Val Leu Phe Ala Ala Ala Ala Val Phe Gly Leu

1 5 10 15

Ala Ala Ala Tyr Asp Glu Val Thr Glu Cys Pro Ala Thr Glu Phe Val

20 25 30

Lys Leu Ala Pro Leu Ala Ala Asn Pro Asn Leu Asn Thr Cys Gln Ala

35 40 45

Ala Ser Glu Gly Trp Gln Met Leu Pro Pro Val Gly Tyr Pro Thr Asp

50 55 60

Thr Gln Arg Ala Ala Met Cys Leu Glu Pro Thr Cys Phe Asn Leu Ile

65 70 75 80

Asp Ala Ile Lys Ala Leu Asn Pro Ser Asp Cys Met Leu Val Phe Gly

85 90 95

Asp Val Lys Leu Asn Val Lys Lys Leu Ala Glu Glu Phe Glu Gly Ser

100 105 110

Cys Phe

Claims (7)

1. An Elicitin gene for inducing HR in Pythium ultimum, the gene is PYOD6, and its nucleotide sequence is shown in SEQID NO.1. 2 . The Pythium ultimum immune induction protein encoded by the Elicitin gene of claim 1 , the amino acid sequence of the protein is shown in SEQ ID NO 4. 3 . 3. The expression cassette, recombinant expression vector, transgenic cell line or transgenic recombinant bacteria containing the Elicitin gene of claim 1. 4. The recombinant expression vector according to claim 3, wherein the starting vector of the recombinant expression vector is the expression vector PBIN-PLUS. 5. Use of the Elicitin gene described in claim 1, the protein described in claim 2 or the recombinant expression vector described in claim 3 or 4 in inducing plant necrosis. 6. Use of the Elicitin gene described in claim 1, the protein described in claim 2 or the recombinant expression vector described in claim 3 or 4 in inducing HR response in plants. 7. a method for inducing plant HR response, is characterized in that, the Elicitin class gene described in claim 1 or the recombinant expression vector described in claim 3 or 4 is introduced in plant, stimulates plant HR response, improves plant resistance. sex.

Images