CN114989275B - Application of OsERF940 protein in improving rice blast resistance - Google Patents

Abstract

The invention discloses an application of OsERF940 protein in improving rice blast resistance. The invention provides an application of any one of the following 1) -3) in regulating and controlling plant rice blast resistance; 1) Protein OsERF940; 2) A nucleic acid molecule encoding the protein OsERF940; 3) A recombinant vector, expression cassette or recombinant bacterium comprising a nucleic acid molecule encoding a protein OsERF940; the protein OsERF940 is a protein composed of an amino acid sequence shown as a sequence 1 in a sequence table. The invention claims the application of OsERF940 protein to increase the expression of rice disease resistance related genes and improve the resistance of rice to rice blast. The invention has great application value for cultivating rice blast resistant rice varieties.

Description

Application of OsERF940 protein in improving rice blast resistance

Technical field

The invention belongs to the field of biotechnology, and specifically relates to the application of OsERF940 protein in improving rice blast resistance.

Background technique

Ethylene response factors (ERF) belong to a subfamily of the ERF/AP2 superfamily. Their common feature is that they contain a conserved ERF domain, which regulates plant responses to biotic and abiotic stresses. A large number of genes encoding ERF factors have also been isolated from different plants. Related research around these genes has become a new highlight in the field of plant genomics. A large number of studies at home and abroad have shown that ERF plays an important role in plant disease resistance responses. For example, research at the University of Missouri in the United States has shown that the ERF factor ERF6 plays an important role in the formation of resistance to gray mold in Arabidopsis. Zhang Zengyan’s research group at the Crop Research Institute of the Chinese Academy of Agricultural Sciences found that overexpression of the wheat ERF factor ERF1 can significantly inhibit the growth of Rhizoctonia glutinosa and improve wheat resistance to sheath blight. Research from the University of Jena in Germany shows that overexpression of the rice ERF factor OsEREBP1 improves rice resistance to bacterial blight. Research by Zhang Shuzhen’s research group at Northeast Agricultural University found that soybean ERF factors improve soybean resistance to Phytophthora root rot. The above-mentioned domestic and foreign studies have shown that EFR factors play an important role in regulating resistance to various crop diseases in different crops.

However, compared with the extensive research on ERF gene functions in Arabidopsis, the functions of most rice ERF family genes and their regulatory relationships in disease resistance responses are still unclear.

Contents of the invention

The purpose of the present invention is to provide the application of OsERF940 protein in improving rice blast resistance.

The present invention claims the application of OsERF940 protein to increase rice blast resistance.

The present invention also protects the application of OsERF940 gene in cultivating transgenic plants with increased rice blast resistance.

The invention also protects a plant breeding method, which includes the following steps: increasing the activity and/or content of OsERF940 protein in target plants, thereby improving the plant's rice blast resistance.

The invention also protects a method for preparing transgenic plants, which includes the following steps: introducing the OsERF940 gene into the starting plant to obtain a transgenic plant with increased rice blast resistance compared with the starting plant.

The OsERF940 protein is specifically derived from Oryza sativa L. Zhonghua 11, an Asian cultivated rice species.

Any of the above OsERF940 proteins is as follows (a) or (b) or (c) or (d) or (e):

(a) The protein shown in Sequence 1 of the sequence listing;

(b) Proteins derived from Sequence 1 that are related to the increase in plant blast disease, obtained by substituting and/or deleting and/or adding one or several amino acid residues in Sequence 1;

(c) A protein derived from rice that has more than 95% identity with (a) and is related to rice blast resistance;

Any of the above OsERF940 genes is a gene encoding the OsERF940 protein.

Any of the above OsERF940 genes is specifically a DNA molecule as described in (1) or (2) or (3) or (4) as follows:

(1) The DNA molecule whose coding region is as shown in Sequence 2 in the sequence listing;

(2) A DNA molecule that has more than 75% identity with (1) and encodes a protein related to plant rice blast disease resistance;

(3) DNA molecules derived from rice and having more than 90% identity with (1) and encoding proteins related to rice blast disease resistance;

(4) DNA molecules that hybridize with (1) under stringent conditions and encode proteins related to plants and plant blast disease resistance;

Any of the above mentioned plants is a monocotyledonous plant or a dicotyledonous plant. The monocotyledonous plant is a gramineous plant. The gramineous plant is a plant of the genus Oryza. The Oryza plant is rice, such as Oryza sativa 11.

In any of the above methods, "introducing the OsERF940 gene into the starting plant" is achieved by introducing the recombinant expression vector into the starting plant. The recombinant expression vector is a plasmid obtained by inserting the OsERF940 gene into a plant expression vector and capable of expressing the OsERF940 gene. The recombinant expression vector can be specifically: insert the double-stranded DNA shown in the 1-954th nucleotides of Sequence 2 of the sequence list into the multiple cloning site of the pCAMBIA3301 vector (for example, between the Sac I and BamHI restriction sites). The molecularly obtained recombinant plasmid pCAMBIA3301-OsERF940.

Experiments of the present invention prove that overexpression of the OsERF940 gene of the present invention significantly increases the transcriptional expression of rice disease resistance-related genes and increases rice blast resistance. It shows that OsERF940 protein plays an important role in improving rice blast resistance. The invention has great application value for cultivating rice varieties resistant to rice blast.

Description of drawings

Figure 1 is a schematic diagram of the components of the recombinant plasmid pCAMBIA3301-OsERF940.

Figure 2 shows the relative expression level of OsERF940 gene in transgenic lines, M: nucleic acid molecule marker, Control: control (wild type), T1-T8: RT-PCR detection results of T0 generation plant lines.

Figure 3 shows the qPCR detection of disease resistance gene expression levels in OsERF940 overexpression lines OE3 and OE5.

Figure 4 is a picture of transgenic rice lines inoculated with rice blast in the field and laboratory. WT represents the wild-type control, OE3, OE4, and OE5 represent different transgenic lines; (A) represents the disease resistance phenotype of transgenic materials in the disease spectrum field. ; (B) Represents the disease resistance phenotype of transgenic materials under indoor inoculation conditions.

Detailed ways

The experimental methods used in the following examples are conventional methods unless otherwise specified.

Materials, reagents, etc. used in the following examples can all be obtained from commercial sources unless otherwise specified.

The following examples facilitate a better understanding of the present invention, but do not limit the present invention. The experimental methods in the following examples are all conventional methods unless otherwise specified. The test materials used in the following examples were all purchased from conventional biochemical reagent stores unless otherwise specified. The quantitative experiments in the following examples were repeated three times, and the results were averaged.

The protein shown in Sequence 1 of the sequence listing is named OsERF940 protein. In the rice cDNA, the coding region of OsERF940 protein is shown in Sequence 2 of the sequence listing, which is named OsERF940 gene.

pCAMBIA3301 vector, the full name is pCAMBIA3301-myc plant overexpression vector: Shanghai Jiran Biotechnology Co., Ltd., product catalog number is JR13080311.

Agrobacterium LBA4404: Xingzhi Biotechnology Co., Ltd., product catalog number is AABV02-03.

Rice Floral Repressor Early flowering1 Affects Spikelet Fertility By ModulatingGibberellin Signaling.Rice(N Y).2015Dec;8(1):58.doi: 10.1186/s12284-015-0058-1, available to the public from the applicant.

Magnaporthe oryzae strain (strain GD08-T13) was donated by Li Xiaoxiang, Institute of Rice, Hunan Academy of Agricultural Sciences; recorded in the following documents: Liu Q, Li X, Yan S, Yu T, Yang J, Dong J, Zhang S, Zhao J, Yang T, Mao X, Zhu 1479-y, available to the public from the applicant.

Example 1. Obtaining transgenic plants

1. Construction of recombinant plasmid

1. Extract total RNA from rice Nipponbare and then reverse-transcribe to obtain cDNA.

2. Use the cDNA obtained in step 1 as a template, use the primer pair composed of F1 and R1 to perform PCR amplification, and recover a 236bp PCR amplification product.

F1: 5'-CGGTA GGATCC ATGGTGCCCTCTTCACGGGAAAG-3'

R1: 5'- CCCCGAGCTC AAGACAGTTGAGTTCTTGTTCCA-3'.

3. Double-digest the PCR amplification product obtained in step 2 with restriction endonuclease Sac I and BamH, and recover the digested product.

4. Use restriction endonuclease Sac I and BamH to double-digest the pCAMBIA3301 vector and recover the vector backbone.

5. Connect the enzyme digestion product obtained in step 3 to the vector backbone obtained in step 4 to obtain the recombinant plasmid pCAMBIA3301-OsERF940.

According to the sequencing results, the recombinant plasmid pCAMBIA3301-OsERF940 is a plasmid obtained by inserting the DNA molecule shown in positions 1-951 of Sequence 2 of the sequence list between the Sac I and BamH restriction sites of the pCAMBIA3301 vector. This plasmid contains OsERF940 Coding sequence of the gene, expressing protein OsERF940.

The schematic diagram of the components of the recombinant plasmid pCAMBIA3301-OsERF940 is shown in Figure 1.

2. Obtaining OsERF940 transgenic rice

1. Introduce the recombinant plasmid pCAMBIA3301-OsERF940 into Agrobacterium LBA4404 to obtain the recombinant Agrobacterium.

2. Suspend the recombinant Agrobacterium obtained in step 1 in the liquid ASAA culture medium to obtain a bacterial liquid with an OD _600nm value = 0.3.

Liquid ASAA medium: liquid NB medium containing 2 mg/L 2,4-D and 100 μM/L AS.

3. Take the seeds of rice Zhonghua 11 (hereinafter referred to as wild-type rice), sterilize them with 75% ethanol, then place them on a solid NB medium plate, cultivate them in the dark at 28°C for 2 weeks, and then transfer the calli to a new medium. The callus was cultured on a solid NB medium plate at 28°C in the dark for 2 weeks, and then the calli were transferred to a new solid NB medium plate and cultured in the dark at 28°C for 2 weeks.

4. After completing step 3, place the naturally dispersed, light yellow embryogenic callus particles in the callus on the subculture medium plate and culture them in the dark at 28°C for 3 days.

Subculture medium: solid NB medium containing 2 mg/L 2,4-D.

5. After completing step 4, take the callus and soak it in the bacterial solution obtained in step 2 for 10-20 minutes, shaking gently during this period.

6. After completing step 5, take the callus tissue, use filter paper to absorb the bacterial liquid on the surface, and then place it on the co-culture medium plate and cultivate it in the dark at 21°C-22°C for 3 days.

Co-culture medium: solid NB medium containing 2 mg/L 2,4-D and 100 μM AS.

7. After completing step 6, take the callus and place it on the screening medium plate and cultivate it in the dark at 28°C for 2 weeks. Then transfer the callus to a new screening medium plate and cultivate it in the dark at 28°C for 2 weeks. Then put the callus The injured tissue was transferred to a new screening medium plate and cultured in the dark at 28°C for 2 weeks.

Screening medium: solid NB medium containing 2 mg/L 2,4-D and 50 mg/L Bar.

8. After completing step 7, take the vigorously growing, milky white or slightly yellow fresh callus, place it on the pre-differentiation medium plate, culture it in the dark at 28°C for 1 week and then in the light at 28°C for 2 weeks, and then transfer to the differentiation medium. On the medium plate, culture at 28°C under light to obtain differentiated seedlings.

Predifferentiation medium: solid NB medium containing 5 mg/L ABA and 0.5 mg/L NAA.

Differentiation medium: solid NB medium containing 0.5 mg/L NAA and 3 mg/L 6-BA.

9. After completing step 8, transfer the well-differentiated seedlings to an Erlenmeyer flask containing solid MS culture medium. Cultivate in the light at 28°C for 1-2 weeks and then transplant to the greenhouse. Continue cultivating until the seeds are harvested, which is T _1st generation seeds.

10. Cultivate T ₁ generation seeds into plants, which are T ₁ generation plants. The T ₁ generation plants are selfed to obtain T ₂ generation seeds.

12. Cultivate T ₂ generation seeds into plants, which are T ₂ generation plants. The T ₂ generation plants are selfed to obtain T ₃ generation seeds.

13. Cultivate the T _3rd generation seeds into plants, which are T _3rd generation plants.

For a certain T ₁ generation plant, if the following two conditions are met, the T ₁ generation plant is a single-copy inserted transgenic plant: ① The T ₁ generation plant has Bar resistance (2% Basta is used in the field (Company: Beijing Huayueyang Biological Product No.: W9062-100ml) sprayed three-leaf one-year-old rice seedlings, and after 1 week of treatment, screened green rice seedlings, which were positive transgenic materials); ② Among the T _2- generation plants obtained from self-crossing of the T _1- generation plants , the number ratio of Bar-resistant plants to non-Bar-resistant plants is basically consistent with 3:1 (after Basta screening, the Basta-resistant seedlings of rice plants (about 50 plants) in the strain: Basta-sensitive seedlings ≈ 3:1).

For a certain T ₂ generation plant, if the following three conditions are met, the T ₂ generation plant and its selfed progeny are a homozygous transgenic line: ① The T ₂ generation plant is Bar resistant (field use 2 % Basta was sprayed on 3-leaf and one-center-old rice seedlings, and the rice seedlings remained green after 1 week of treatment); ② Its T ₁ generation plants are single-copy inserted transgenic plants (after Basta screening, the Basta of the rice plants in the line (about 50 plants) Resistant seedlings: Basta-sensitive seedlings ≈ 3:1); ③ The T _3- generation plants sampled and tested are all Bar-resistant (3-leaf one-year-old rice seedlings were sprayed with 2% Basta in the field, and the rice seedlings remained green after 1 week of treatment) .

3. PCR identification

Randomly select two lines from the homozygous transgenic lines obtained in step 2, the OE1 line and the OE2 line, and identify the T ₂ generation plants. Rice Zhonghua 11 was used as the wild-type control of the transgenic line.

Total RNA from plants (4-week-old seedlings) was extracted and reverse transcribed into cDNA. The cDNA was used as a template to identify the expression level of OsERF940 gene by quantitative PCR.

The primers for qPCR identification of OsERF940 gene are as follows:

F2: 5'-GATGAGATTCCTGTGAGCAAC-3';

R2: 5'-GTTCCAATGAAGCAAAGTCGA-3'.

Taking the expression level of OsERF940 in rice Zhonghua 11 as 1, the relative expression level of OsERF940 gene in homozygous transgenic lines was calculated.

The results are shown in Figure 2. It can be seen that the expression levels of ERF940 in the eight T2 generation lines are higher than those in the control, indicating that the eight T2 generation lines obtained are positive OsERF940 transgenic rice.

Example 2. Detection of disease resistance-related gene expression in rice transgenic with OsERF940 gene

The T2 generation plants of positive OsERF940 transgenic rice were used as the test plants below.

Test plants: T ₂ generation plants of OE3 strain, T ₂ generation plants of OE5 strain and rice Zhonghua 11 plant (WT).

Total RNA was extracted from the test plant leaves (4-week-old seedlings), reverse transcribed into cDNA, and the cDNA was used as a template to identify the expression levels of each related gene through quantitative PCR. Taking the expression level of disease resistance-related genes in rice Zhonghua 11 as 1, the relative expression levels of disease resistance-related genes in transgenic lines were calculated.

The primers used to identify the OsMYC2 gene are as follows:

Upstream primer: 5'-ATCATGACTAGAGAGGAGCA-3';

Downstream primer: 5'-CCAACACGAGCCTCACAATCA-3';

The primers used to identify the PR1 gene are as follows:

Upstream primer: 5'-GCGCTGCAGGAGGACTACGTA-3';

Downstream primer: 5'-CCCTCCGGCACAAGTATACA-3'.

The primers used to identify the PR4 gene are as follows:

Upstream primer: 5'-CTTCAAGAAGATCGACACAGA-3';

Downstream primer: 5'-CAGAGTGCCAACCTCTTCCA-3'.

The primers used to identify the Chitinase gene are as follows:

Upstream primer: 5'-TTGGCGGCGGTGCAGTGAACA-3';

Downstream primer: 5'-CATGCATATATATCGGTTTCA-3'.

Taking the expression level of 11 genes in rice flowers as 1, the relative expression level of the corresponding genes in the transgenic lines was calculated.

The results are shown in Figure 3. The relative expression levels of disease resistance-related genes in the T _2- generation OsERF940 transgenic rice were higher than those in the wild-type rice variety Zhonghua 11 plants, indicating that overexpression of the OsERF940 gene can significantly increase OsMYC2 and PR1. , PR4 and Chitinase and other rice disease resistance related genes expression.

The above results show that the OsERF940 gene plays an important role in regulating the expression of rice disease resistance-related genes. Overexpression of the OsERF940 gene can improve rice blast resistance by increasing the expression of disease resistance-related genes.

Example 3. Analysis of rice blast disease of transgenic plants

Test plants: rice Zhonghua 11 plant (WT, control), T ₂ -generation OsERF940 transgenic rice plants of OE1-OE8 lines.

1. Field testing

The test plants were planted in the experimental field and were planted according to the requirements of production and inoculation specifications.

Figure 4A is a photograph of rice blast disease in OE3, OE4, OE5 and rice Zhonghua 11.

The disease resistance of field test plants was tested according to the International Rice Research Institute rice blast resistance classification standard (Master's thesis of Xiao Junzhi of Central South University in May 2011 "Selection of core germplasm of heterogeneous local rice resources in Hunan").

The results are shown in Table 1 below. It can be seen that compared with the control, the transgenic lines are all resistant to leaf blast.

Table 1 shows the statistics of disease resistance of transgenic lines of Magnaporthe oryzae inoculated

2. Indoor testing:

Inoculate the filter paper piece containing the blast fungus strain (strain GD08-T13) into the starch medium (2g yeast extract, 10g soluble starch, 15g agar powder, add water to make the volume to 1L water), and activate and culture at 26°C for 7 days , then inoculate the activated mycelium into oat culture medium (sugar-free oatmeal 50g/beat to powder, 20g sucrose, 20g agar, add water to make the volume to 1L), and cultivate in the dark at 26°C for 7 days until the mycelium is full. After the culture medium, the hyphae are scraped off, and the culture is continued to produce spores for 3-4 days under constant light and moisture. After that, the test plant rice Zhonghua 11, the T _2- generation OsERF940 gene-transformed rice OE3 and the T ₂ -generation OsERF940 gene-transformed rice OE5 seedlings in the three-leaf and one-heart stage were respectively inoculated with M. oryzae: wash the growth medium on the culture medium with sterilized water. spores, adjust the spore concentration to 5 × 10 ⁵ /mL, and add 2/10,000 Tween20, use a small sprayer to evenly spray the spore solution onto the surface of the rice leaves (three-leaf, one-heart stage rice seedlings) (the dosage is to make the leaves uniform moist).

Immediately cover the seedlings with a custom-made plexiglass cover and place them in an artificial climate box in the dark at 25°C for 24 hours, and then switch to normal light conditions. The incidence of disease will be investigated 5-7 days after vaccination.

The results are shown in Figure 4B. Photos of rice blast diseases of different materials after laboratory inoculation. It can be seen that compared with rice Zhonghua 11 (WT), the incidence of rice blast disease in T _2- generation OsERF940 gene rice plants is significantly weaker than that of rice plants. In Zhonghua 11, the rice blast resistance of transgenic plants was significantly higher than that of the wild-type control, indicating that overexpression of the OsERF940 gene plays an important role in improving rice blast resistance. The OsERF940 gene can improve rice blast resistance by increasing the expression of rice disease resistance-related genes.

SEQUENCE LISTING

<110> Institute of Biotechnology, Chinese Academy of Agricultural Sciences

<120> Application of OsERF940 protein in improving rice blast resistance

<160> 2

<170> PatentIn version 3.5

<210> 1

<211> 317

<212> PRT

<213> Oryza sativa L.

<400> 1

Met Val Pro Ser Ser Arg Lys Val Arg Val Phe Cys Ser Asp Pro Asp

1 5 10 15

Ala Thr Asp Ser Ser Asp Glu Asp Asp Gln Asn Lys Lys Glu Arg Arg

20 25 30

Phe Ser Arg Glu Ile Leu Ile Pro Met Glu Asn Ser Lys Ala Ser Lys

35 40 45

Pro Val Lys Thr Leu Val Gln Cys Gly Thr Lys Thr Val Lys Asp Ser

50 55 60

Glu Lys Glu Pro Thr Ser Lys Tyr Arg Gly Val Arg Arg Arg Ala Trp

65 70 75 80

Gly Lys Trp Ala Ala Glu Ile Arg Asp Pro Val Arg Lys Ser Arg Lys

85 90 95

Trp Ile Gly Thr Phe Asn Ser Glu Glu Glu Ala Ala Ala Ala Tyr Leu

100 105 110

Ala Gln Ser Asn Gln Phe His Glu Glu Leu Met Ala Leu Lys Ile Gln

115 120 125

Ser Ser Val Ser Glu Gln Glu Asp Leu Ser Ser Ser Val Thr Ile Ser

130 135 140

Cys Val Ser Ser Ser Gln Ser Cys Asp Gln Lys Ile Gln Ala Lys Pro

145 150 155 160

Gln Glu His Lys Arg Val Ser Val Val Val Asn Arg Glu Thr Val Glu

165 170 175

Gln Lys Phe Lys Ala Gln Pro Gln Ala Gln Lys Ile Lys Ala Gln Pro

180 185 190

Glu Val Gln Lys Arg Val Ser Val Lys Ile Ser His Glu Thr Glu Asp

195 200 205

Glu His Leu Leu Asn Leu Pro Ser Thr Pro Lys Gly Lys Glu Ile Ser

210 215 220

Met Gly Ala Val Leu Gly Arg Ile Asp Glu Ile Pro Val Ser Asn Cys

225 230 235 240

Val Gly His Ile Asp Glu Phe Pro Pro Asp Asp Phe Thr Arg Leu Ala

245 250 255

Asp Ala Phe Pro Val Ser Asp Phe Ile Gly Met Ala Asp Val Pro Leu

260 265 270

Gly Asp Asp Tyr Ile Gly Leu Ala Asp Ile Ser His Leu Pro Leu Pro

275 280 285

Ile Thr Asp Leu Lys Phe Asp Leu Asn Ala Glu Leu Asn Trp Asp Gly

290 295 300

Phe Asp Phe Ala Ser Leu Glu Gln Glu Leu Asn Cys Leu

305 310 315

<210> 2

<211> 954

<212> DNA

<213> Oryza sativa L.

<400> 2

atggtgccct cttcacggaa agtccgtgtt ttctgctctg atcctgatgc cactgactcc 60

tctgatgaag atgaccagaa taagaaggaa aggagattt caagggaaat actaattcca 120

atggaaaact ccaaggcatc caaacctgtt aagacccttg ttcaatgtgg cacaaagact 180

gtaaaggatt ccgagaagga accgacgagc aaatacaggg gtgtgcgccg gcgggcgtgg 240

ggcaaatggg ctgcagaaat acgtgaccct gtgcgaaaat caaggaaatg gattggcaca 300

tttaacagtg aggaggaggc cgctgcggca tatcttgcac aatcaaacca gttccatgaa 360

gagttgatgg ccttgaaaat ccaatcttct gtatcagagc aggaagattt gtcaagctct 420

gttactatat cctgcgtgtc ctcatctcag tcatgtgacc agaagattca ggcaaagcca 480

caagaacaca agagagtgtc agtggtggtt aaccgtgaga ccgttgagca gaagtttaag 540

gcacagccac aagctcagaa gattaaggca cagccagaag tgcagaagag agtgtcagtg 600

aagattagcc atgagactga ggatgagcac ttgctgaact tgccgtccac gcctaaaggc 660

aaagagattt cgatgggcgc tgttcttggc aggatagatg agattcctgt gagcaactgt 720

gtgggccata ttgatgaatt tccacctgat gatttcacta ggcttgcaga tgcgttccca 780

gttagtgatt ttatcggcat ggcagatgtg ccactgggcg atgattacat tggccttgca 840

gacatcagcc acctgccgct gcctatcaca gatctgaagt tcgacctcaa tgcagaactc 900

aactgggacg ggttcgactt tgcttcattg gaacaagaac tcaactgtct ttga 954

Claims (6)

1. The application of any of the following substances 1) to 3) in improving plant resistance to rice blast; 1) Protein OsERF940; 2) Nucleic acid molecules encoding protein OsERF940; 3) Recombinant vectors, expression cassettes or recombinant bacteria containing nucleic acid molecules encoding protein OsERF940; The protein OsERF940 is as follows (1) or (2): (1) A protein consisting of the amino acid sequence shown in Sequence 1 in the sequence listing; (2) A protein consisting of a tag sequence added to the end of the amino acid sequence shown in Sequence 1 in the sequence listing; The plant is rice. 2. Application according to claim 1, characterized in that: The nucleic acid molecule encoding protein OsERF940 is a DNA molecule in any one of the following 1)-2): 1) The coding region is the DNA molecule shown in sequence 2 in the sequence listing; 2) The DNA molecule shown in positions 1-951 of Sequence 2 in the sequence listing. 3. Application of any one of the substances 1) to 3) in claims 1 or 2 in cultivating blast-resistant rice. 4. Application of any one of the substances 1) to 3) in claims 1 or 2 in cultivating rice with improved rice blast resistance. 5. A method of cultivating transgenic plants with improved rice blast resistance, which is as follows 1) or 2): 1) The method includes the following steps: increasing the content and/or activity of the protein OsERF940 in the target plant to obtain a transgenic plant; 2) The method includes the following steps: improving the expression of the nucleic acid molecule encoding the protein OsERF940 in the target plant to obtain a transgenic plant; The rice blast resistance of the transgenic plant is higher than that of the target plant; The protein OsERF940 is as follows (1) or (2): (1) A protein composed of the amino acid sequence shown in Sequence 1 in the sequence listing; (2) A protein consisting of a tag sequence added to the end of the amino acid sequence shown in Sequence 1 in the sequence listing; The plant is rice. 6. The method according to claim 5, characterized in that: The method of increasing the content and/or activity of protein OsERF940 in a target plant, or the method of increasing the expression of a nucleic acid molecule encoding protein OsERF940 in a target plant, involves introducing the nucleic acid molecule encoding protein OsERF940 into the target plant.