SNP molecular marker related to bruchid resistance in mung bean and its application in genetic breeding

Abstract

This invention discloses a SNP molecular marker associated with mung bean resistance to the bean weevil and its application in genetic breeding. The problem this invention aims to solve is how to identify mung bean resistance to the bean weevil. The SNP molecular marker is a locus (SNP site) on mung bean chromosome 4, with a nucleotide type of T or C, located at nucleotide position 164 of sequence 3 in the sequence listing. This invention provides the application of substances for detecting polymorphisms or genotypes of SNP sites in the mung bean genome in identifying or assisting in the identification of mung bean resistance to the bean weevil. This invention can be used to assist in the identification of mung bean resistance to the bean weevil, for early screening of mung beans, and for marker-assisted breeding of mung beans.

Description

Technical Field

[0001] This invention relates to the fields of molecular biology and genetic breeding technology, and in particular to SNP molecular markers related to mung bean resistance to bean weevil and their application in genetic breeding. Background Technology

[0002] Mung bean (Vigna radiata (Linn.) Wilczek.) has been cultivated in China for two thousand years and is an important food crop. In recent years, with the adjustment of the planting structure and changes in people's dietary structure, the demand for mung beans has been increasing, and the planting area has been expanding year by year. Studies have shown that pests and diseases seriously affect mung bean seed germination and yield. In view of this, in-depth research on the genes involved in bean weevil resistance and the insect resistance mechanism in bean weevil-resistant mung bean varieties is of great significance for screening superior varieties with strong bean weevil resistance and for screening bean weevil-resistant breeding materials.

[0003] The bean weevil (Callosobruchus chinensis Linnaeus), belonging to the order Coleoptera, family Leguminosae, and genus Callospermum, is a global storage pest. It primarily feeds on legumes rich in carbohydrates and protein but low in fat, such as mung beans, adzuki beans, cowpeas, broad beans, peas, and chickpeas, with a particular preference for mung beans. Initial infestations typically occur in the field; adults feed on pollen and lay eggs on mung bean pods, which are then carried into storage, continuing the damage. After adult emergence, secondary and even multiple infestations can occur, leading to mold growth and potentially rendering all stored mung beans unusable. Furthermore, the bean weevil has a high reproductive rate, making it difficult to eradicate once an infestation occurs, resulting in severe damage. Therefore, it is necessary to breed bean weevil-resistant mung bean varieties, and using high-throughput molecular marker-assisted selection platforms is an effective means to improve the efficiency and accuracy of pest and disease resistance breeding. Summary of the Invention

[0004] The problem to be solved by this invention is how to identify or assist in the identification of mung bean weevil resistance.

[0005] To address the above technical problems, this invention first provides the application of a substance for detecting polymorphisms or genotypes of SNP sites in the mung bean genome.

[0006] The application provided by this invention is the use of substances for detecting SNP site polymorphisms or genotypes in the mung bean genome in any of the following applications.

[0007] (1) To identify or assist in the identification of mung bean weevil resistance;

[0008] (2) Screening or breeding mung bean single plants, lines, strains or varieties resistant to bean weevil;

[0009] (3) Screening or breeding mung bean single plants, lines, strains or varieties susceptible to bean weevil;

[0010] (4) Mung bean breeding;

[0011] (5) Prepare products for identification or auxiliary identification of mung bean weevil resistance;

[0012] (6) Prepare or select mung bean single plants, lines, strains or varieties resistant to bean weevil;

[0013] (7) Prepare products of single mung bean plants, lines, strains or varieties that are susceptible to bean weevil;

[0014] (8) Prepare mung bean breeding products;

[0015] The SNP site is a site on chromosome 4 of the mung bean, and its nucleotide type is T or C, which is the 164th nucleotide of sequence 3 in the sequence listing.

[0016] Using the genome sequence of Zhonglv No. 5 as a reference genome, the SNP site is located at 10060247 bp on chromosome 4 of mung bean (specifically, position 164 of sequence 3 in the sequence listing).

[0017] This invention also provides a method for identifying or assisting in the identification of mung bean weevil resistance.

[0018] The method for identifying or assisting in the identification of mung bean weevil resistance provided by the present invention includes detecting the genotype of the SNP locus in the genome of the mung bean to be tested, and identifying or assisting in the identification of mung bean weevil resistance based on the genotype. The genotype is TT, TC or CC, where TT is a homozygous type with the SNP locus being T, CC is a homozygous type with the SNP locus being C, and TC is a heterozygous type with the SNP locus being both T and C.

[0019] Optionally, according to the above method, the identification or auxiliary identification of mung bean weevil resistance can be carried out in any of the following ways:

[0020] (1) The mung beans to be tested with the genotype TT or TC at the SNP locus are or candidates for mung beans resistant to bean weevil.

[0021] (2) The mung bean with the genotype CC at the SNP site is a mung bean that is susceptible to bean phenotype.

[0022] (3) The bean weevil resistance of the mung bean with the genotype TT or TC at the SNP site is higher than that of the mung bean with the genotype CC at the SNP site.

[0023] As one implementation scheme, the method for identifying or assisting in the identification of mung bean weevil resistance may include the following steps:

[0024] (1) Sequencing was performed using the genomic DNA of the mung bean to be tested as a template and a primer composition was used; the primer composition consisted of primer A and primer B;

[0025] Primer A is a single-stranded DNA molecule whose nucleotide sequence is sequence 1 in the sequence listing;

[0026] Primer B is a single-stranded DNA molecule whose nucleotide sequence is sequence 2 in the sequence listing;

[0027] (2) After completing step (1), determine the genotype of the SNP site of the mung bean to be tested;

[0028] (3) Identify the bean weevil resistance of the mung beans to be tested based on the genotype results: the bean weevil resistance of the mung beans to be tested with the genotype TT or TC at the SNP site is higher than that of the mung beans to be tested with the genotype CC at the SNP site.

[0029] In the above method, the PCR reaction procedure can be as follows: Step 1: 95℃ pre-denaturation for 5 min; Step 2: 95℃ denaturation for 30 s, 55℃ annealing for 45 s, 72℃ extension for 45 s, 32-35 cycles; Step 3: 72℃ extension for 5 min.

[0030] The application of the above-described method in mung bean breeding also falls within the scope of protection of this invention.

[0031] This invention also provides a method for breeding mung beans.

[0032] The mung bean breeding method provided by this invention is M1 or M2:

[0033] M1. The method includes detecting the genotype of the SNP site in the mung bean genome, selecting mung beans with the genotype of TT or TC at the SNP site as parents for breeding, wherein TT is a homozygous type with the SNP site being T, and TC is a heterozygous type with the SNP sites being T and C. The breeding objective of the method includes selecting mung beans with resistance to bean weevils.

[0034] M2. The method includes detecting the genotype of the SNP site in the mung bean genome, selecting mung beans with the genotype CC at the SNP site as parents for breeding, wherein CC is a homozygous type of the SNP site C, and the breeding objective of the method includes selecting mung beans susceptible to bean weevils.

[0035] As an implementation method, mung bean breeding methods may include the following steps:

[0036] (1) Using the genomic DNA of the mung bean to be tested as a template, PCR amplification was performed using the above primer set;

[0037] (2) After completing step (1), perform sequencing to determine the genotype of the SNP site of the mung bean to be tested;

[0038] (3) Select mung beans with the TT genotype for breeding against bean weevil.

[0039] This invention also provides products for detecting polymorphisms or genotypes of SNP sites in the mung bean genome.

[0040] The product provided by this invention for detecting the polymorphism or genotype of the SNP sites in the mung bean genome includes the aforementioned substance for detecting the polymorphism or genotype of the SNP sites in the mung bean genome, and the product may be any of the following:

[0041] C1) Products that detect single nucleotide polymorphisms or genotypes related to resistance to bean weevil in mung beans;

[0042] C2) Products used for identification or auxiliary identification of mung bean weevil resistance;

[0043] C3) Products used in mung bean breeding;

[0044] C4) Screening or breeding of mung bean single plants, lines, strains or varieties resistant to bean weevil;

[0045] C5) Screening or breeding of mung bean single plants, lines, strains or varieties susceptible to bean weevil;

[0046] In the above applications, methods, and products, the substance may be a reagent and / or instrument required to determine the polymorphism or genotype of the SNP site by at least one of the following methods: DNA sequencing, restriction fragment length polymorphism, single-strand conformation polymorphism, denaturing high-performance liquid chromatography, and SNP chips. The SNP chips include chips based on nucleic acid hybridization reactions, chips based on single-base extension reactions, chips based on allele-specific primer extension reactions, chips based on one-step reactions, chips based on primer ligation reactions, chips based on restriction endonuclease reactions, chips based on protein-DNA binding reactions, and chips based on fluorescent molecule-DNA binding reactions.

[0047] Optionally, the substance is D1), D2), or D3):

[0048] D1) The substance described is a primer composition for amplifying mung bean genomic DNA fragments including the SNP sites;

[0049] D2) The substance described is a PCR reagent containing the primer composition described in D1);

[0050] D3) The substance is a kit containing the primer composition described in D1) or the PCR reagent described in D2).

[0051] Optionally, the amplification may be PCR amplification. The primer composition consists of primer A and primer B.

[0052] The present invention also provides a DNA molecule, the nucleotide sequence of which is shown in Sequence 3 of the sequence listing.

[0053] The applications of the aforementioned DNA molecules also fall within the scope of protection of this invention. Specifically, the applications are those found in any of the following:

[0054] (1) To identify or assist in the identification of mung bean weevil resistance;

[0055] (2) Screening or breeding mung bean single plants, lines, strains or varieties resistant to bean weevil;

[0056] (3) Screening or breeding mung bean single plants, lines, strains or varieties susceptible to bean weevil;

[0057] (4) Mung bean breeding;

[0058] (5) Prepare products for identification or auxiliary identification of mung bean weevil resistance;

[0059] (6) Prepare or select mung bean single plants, lines, strains or varieties resistant to bean weevil;

[0060] (7) Prepare products of single mung bean plants, lines, strains or varieties that are susceptible to bean weevil;

[0061] (8) Prepare mung bean breeding products.

[0062] Optionally, in the above applications, the DNA molecule serves as a detection target.

[0063] In this study, the bean weevil resistance of mung beans resistant to bean weevil was higher than that of mung beans susceptible to bean weevil.

[0064] In this article, the mung bean resistant to bean weevil can specifically refer to mung beans with a seed damage rate of less than or equal to 65%.

[0065] In this article, the mung beans susceptible to bean weevil can specifically refer to mung beans with a seed damage rate greater than 65%.

[0066] The bean weevil described in this invention may be any of the following: 1) insects of the family Bruchidae; 2) insects of the genus Callosobrus; 3) green bean weevil Callosobrus chinensis (Linnaeus).

[0067] In this invention, the breeding objective may include cultivating mung beans resistant to bean weevils.

[0068] The substance that detects the SNP site polymorphism and genotype can be combined with other substances (such as substances that detect single nucleotide polymorphisms or genotypes of other molecular markers associated with mung bean resistance to bean weevil) to prepare a product for identifying mung bean resistance to bean weevil.

[0069] This invention provides a SNP molecular marker significantly associated with mung bean weevil resistance. This marker is accurate, efficient, convenient, and stable in detection, and can be used for marker-assisted selection to improve the identification efficiency of different mung bean varieties resistant to the bean weevil. This invention can be used to assist in the identification of mung bean resistance to the bean weevil, for early screening of mung beans, and for marker-assisted breeding of mung beans. This invention has advantages such as simple operation, low cost, short detection cycle, and marker stability, and has significant application value in the research of discovering bean weevil-resistant mung bean germplasm resources and breeding bean weevil-resistant mung bean varieties. Detailed Implementation

[0070] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0071] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0072] The grading criteria for resistance to bean weevil are shown in Table 1.

[0073] Table 1 Grading Standards for Mung Bean Resistance to Bean Wee

[0074]

[0075]

[0076] Seed damage rate = Number of damaged seeds / 50 * 100 (In this experiment, 50 seeds were randomly selected from each sample, and the total number of seeds was 50).

[0077] Example 1: Detection of resistance to bean weevil in mung beans using SNPs

[0078] 1. Discovery of SNP markers associated with resistance to mung bean weevil disease

[0079] Thirty-five hundred mung bean varieties (Table 2) were selected from global core mung bean germplasm resources as experimental materials to identify bean weevil resistance. Fifty healthy seeds were randomly selected from each material, including two control groups of susceptible bean weevil variety Zhonglv 1 (50 seeds each). These were placed in plastic boxes in a bean weevil resistance identification chamber, with the temperature maintained between 25℃ and 29℃ and the humidity controlled between 70% and 80%. Four hundred to five hundred newly emerged adult bean weevils (1-3 days old) were placed in each box and allowed to lay eggs randomly. When more than five eggs were laid on each seed, the adults were removed. After 40-45 days, the number of resistant seeds and the resistance rate were investigated. Resistance was evaluated for each individual plant according to the method described by Cheng Xuzhen et al. (《Mung Bean Germplasm Resource Description Specifications and Data Standards》2006). Materials achieving moderate resistance or higher were repeatedly tested in triplicate. Resequencing of the above mung bean germplasm resources yielded 648,408 high-quality SNP markers.

[0080] Combining the previously determined mung bean seed bean weevil resistance and the 648,408 SNP markers in this population, a genome-wide association study (GWAS) was performed using GEMMA software. The results showed that a single SNP marker located on chromosome 4, at nucleotide 10,060,247, was significantly associated with mung bean seed bean weevil resistance. This SNP was repeatedly detected in two years, with -LOG10(P) values ​​greater than 30 (-LOG10(P) = 34.7). The SNP site differs between the T and C bases. This SNP site (abbreviated as SNP-10060247) and its surrounding nucleotides are shown in Sequence 3 of the sequence listing, where nucleotide 164 is the SNP site, exhibiting a C / T polymorphism. In Sequence 3, y represents either C or T. The genotypes of this SNP site are CC, TC, or TT. CC is the homozygous genotype of the SNP locus C, TT is the homozygous genotype of the SNP locus T, and TC is the heterozygous genotype of both the SNP locus T and C. Mung bean varieties with the genotype TT or TC at this SNP locus exhibit significantly higher resistance to bean weevils than mung bean varieties with the genotype CC at this SNP locus.

[0081] (4) Haplotype analysis

[0082] Genotypic analysis was performed using SNP markers and resistance phenotype data of 350 mung bean weevil-affected materials. The results are shown in Table 2. The SNP genotypes were divided into three groups: CC, CT, and TT. The resistance of mung bean weevil-affected genotypes TT and CT was significantly higher than that of the CC genotype.

[0083] 2. Establishment of a method for detecting resistance to bean weevils in mung beans

[0084] Based on the SNP site information and the whole genome sequence information of mung bean, SNP marker primers were developed. The upstream primer F is sequence 1 in the sequence listing: 5'-GAATGGTAAGTGTTCTGCAAT-3'; the downstream primer R is sequence 2 in the sequence listing: 5'-TCACCAGAAGATGAGAATGCTC-3'. The amplified size was 237 bp, and the SNP site was located at 164 bp of the amplified fragment. The above primer combination was used to detect the variation (SNP-10060247) at base position 10060247 on chromosome 4 of mung bean.

[0085] 2.1 Extraction of genomic DNA from mung bean leaves to be tested

[0086] DNA was extracted from fresh leaves during the seedling stage using the CTAB method. The detailed steps are as follows:

[0087] 1) Add 800 μL of CTAB mixed extraction solution, vortex for 1 min to mix evenly, place the centrifuge tube in a 65℃ water bath and incubate for 45 min-1 h.

[0088] 2) Add 800 μL of chloroform / isoamyl alcohol (V / V = 24:1) solution and mix well for 15 min.

[0089] 3) Centrifuge at 10,000 rpm for 10 min in a constant temperature centrifuge, and transfer 600 μL of supernatant (a small amount is acceptable) into a 2 mL centrifuge tube with the corresponding number.

[0090] 4) Add 900 μL of 95% ethanol and 300 μL of 5M NaCl, then slowly invert for 2 min and place in a -20℃ refrigerator for 30 min. White flocculent matter will appear in the centrifuge tube. Then centrifuge at 10000 rpm for 10 min, discard the supernatant, and keep the precipitate.

[0091] 5) Add 500 μL of 90% ethanol to a centrifuge tube, soak for 5-7 minutes, and then centrifuge at 10,000 rpm for 5 minutes.

[0092] 6) Discard the supernatant, dry at room temperature, add 200 μL of ultrapure water to dissolve the DNA, and store at -20℃ for later use.

[0093] 2.2 PCR

[0094] The PCR amplification reaction system included: 40 ng DNA, 1×Taq enzyme buffer (10 mM Tris-HCl, pH 8.8; 10 mM KCl; 10 mM (NH4)2SO4; 1.5 mM MgCl2; 0.1% Triton X-100), 1 mM dNTPs, 0.25 μM each of forward and reverse primers, and 1 U Taq DNA polymerase, with ddH2O added to a final volume of 10 μL. The reaction program was: 95℃ pre-denaturation for 5 min; 95℃ denaturation for 30 s, 55℃ annealing for 45 s, 72℃ extension for 45 s, for 32-35 cycles; and a final extension at 72℃ for 5 min.

[0095] After the reaction, the reaction products were sequenced for genotyping identification. The results showed SNP site variations as shown in Table 2. This included 10 highly resistant, 9 moderately resistant, and 331 highly susceptible bean weevil-prone materials. The bean weevil resistance of the tested mung bean varieties was identified based on the genotype results: the SNP site genotypes were of three types: CC, TC, or TT. CC is homozygous for SNP-10060247 being C, TT is homozygous for SNP-10060247 being T, and TC is heterozygous for SNP-10060247 being both T and C. If the genotype of the tested mung bean variety is TT or TC, then the variety is bean weevil-resistant; if the genotype is CC, then the variety is bean weevil-prone. Meanwhile, as shown in Table 3, among the bean weevil resistance traits, the bean weevil resistance of the homozygous TT genotype mung bean was significantly greater than that of the CT and CC genotype mung bean (P<0.01), and the differences in bean weevil resistance between the heterozygous CT genotype and the homozygous CC genotype were both extremely significant.

[0096] This invention utilizes SNP-10060247 to identify mung bean weevil resistance phenotypes, and the results are consistent with those obtained from identifying mung bean weevil resistance by genotype. Therefore, molecular markers that detect the polymorphism or genotype of SNP-10060247 in the mung bean genome can be used for marker-assisted selection of mung bean weevil resistance to improve the accuracy of selection.

[0097] The percentage of seeds resistant to bean weevil (%) = 1 - seed damage rate (%), and the seed damage rate (%) = number of damaged seeds / 50 * 100 (50 seeds were randomly selected from each sample in this experiment, and the total number of seeds = 50).

[0098] Table 2. Phenotypic and genotypic information on bean weevil resistance in 350 mung bean varieties.

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112] Table 3. Association analysis of genotype at the C>T locus on chromosome 4 of mung bean (base 10060247) with resistance to bean weevil.

[0113] genotype quantity Percentage of seeds resistant to bean weevil (%) TT 10 <![CDATA[89.5±6.07 a ]]> CT 9 <![CDATA[80.56±5.5 b ]]> CC 331 <![CDATA[0.363±1.657 c ]]>

[0114] Note: Different superscript letters in the same column indicate significant differences (P<0.01).

[0115] When breeding mung bean varieties resistant to bean weevil, it is best to select mung beans with the genotype TT or TC at the aforementioned SNP locus as parents for breeding; when breeding mung bean varieties susceptible to bean weevil, it is best to select mung beans with the genotype CC at the aforementioned SNP locus as parents for breeding.

[0116] The present invention has been described in detail above. For those skilled in the art, the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope, and without requiring unnecessary experiments. Although specific embodiments have been given, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including changes made using conventional techniques known in the art that depart from the scope disclosed herein. Some of the essential features can be applied within the scope of the following appended claims. SEQUENCE LISTING <110> Institute of Crop Science, Chinese Academy of Agricultural Sciences <120> SNP molecular markers associated with mung bean resistance to bean weevil and their application in genetic breeding <160> 3 <170> PatentIn version 3.5 <210> 1 <211> 21 <212> DNA <213> Artificial Sequence <400> 1 gaatggtaag tgttctgcaa t 21 <210> 2 <211> 22 <212> DNA <213> Artificial Sequence <400> 2 tcaccagaag atgagaatgc tc 22 <210> 3 <211> 237 <212> DNA <213> Vigna radiata <400> 3 gaatggtaag tgttctgcaa tttcacgggt caacaacggg gttgaaaatt ttcttttacg 60 gaacagcaca tccaattttg caccgcgcct caatccttct tctgagaaaa aattaattgg 120 tttcaagtga tcatgatgat gatgattaac aattgggcct atcyctcgaa gaacaacacc 180 atttttctta ttaccatatc catgatacag taaaagagca ttctcatctt ctggtga 237

Claims

1. The application of substances that detect SNP polymorphisms or genotypes in the mung bean genome in any of the following: (1) To identify or assist in the identification of mung bean weevil resistance in mung beans; (2) Screening or breeding mung bean single plants, lines, strains or varieties resistant to mung bean weevil; (3) Screening or breeding mung bean single plants, lines, strains or varieties susceptible to mung bean weevil; (4) Prepare products for identifying or assisting in the identification of mung bean weevil resistance in mung beans; (5) Prepare or select mung bean single plants, lines, strains or varieties resistant to mung bean weevil; (6) Prepare products by screening or breeding single plants, lines, strains or varieties of mung beans susceptible to mung bean weevil; The SNP site is a site on chromosome 4 of the mung bean, and its nucleotide type is T or C, which is the 164th nucleotide of sequence 3 in the sequence listing.

2. The application according to claim 1, characterized in that: The substance is either D1), D2), or D3). D1) The substance is a primer composition for amplifying mung bean genomic DNA fragments including the SNP sites; D2) The substance is a PCR reagent containing the primer composition described in D1); D3) The substance is a kit containing the primer composition described in D1) or the PCR reagent described in D2).

3. The application according to claim 2, characterized in that: The primer composition consists of primer A and primer B; Primer A is a single-stranded DNA molecule whose nucleotide sequence is sequence 1 in the sequence listing; Primer B is a single-stranded DNA molecule whose nucleotide sequence is sequence 2 in the sequence listing.

4. A method for identifying or assisting in the identification of mung bean weevil resistance in mung beans, characterized in that: This includes detecting the genotype of SNP sites in the genome of the mung bean to be tested, and identifying or assisting in the identification of mung bean weevil resistance based on the genotype. The SNP site is a site on chromosome 4 of the mung bean, and its nucleotide type is T or C, which is the 164th nucleotide of sequence 3 in the sequence listing; the genotype is TT, TC, or CC, where TT is the homozygous type of the SNP site with T, CC is the homozygous type of the SNP site with C, and TC is the heterozygous type of the SNP site with both T and C. The identification or auxiliary identification of mung bean weevil resistance in mung beans is carried out in any of the following ways: 1) The mung beans to be tested with the genotype TT or TC at the SNP locus are or candidates for mung bean resistant to mung bean weevil. 2) The mung beans to be tested with the genotype CC at the SNP locus are or candidates for mung bean phenotypes. 3) The mung bean weevil resistance of the test mung beans with the genotype TT or TC at the SNP site is higher than that of the test mung beans with the genotype CC at the SNP site, and the mung bean weevil resistance of the test mung beans with the genotype TT at the SNP site is higher than that of the test mung beans with the genotype TC at the SNP site.

5. The application of the method described in claim 4 in mung bean breeding.

6. A method for breeding mung beans, characterized by: The method includes detecting the genotype of the SNP locus in claim 1 in the mung bean genome, selecting mung beans with the genotype TT or TC at the SNP locus as parents for breeding, wherein TT is a homozygous type with the SNP locus T, and TC is a heterozygous type with the SNP locus T and C. The mung beans with the genotype TT or TC are mung beans resistant to the mung bean weevil. The breeding purpose of the method is to select mung beans resistant to the mung bean weevil.

7. A method for breeding mung beans, characterized by: The method includes detecting the genotype of the SNP locus in claim 1 in the mung bean genome, selecting mung beans with the genotype CC at the SNP locus as parents for breeding, wherein CC is a homozygous type of the SNP locus C, and the mung bean with the genotype CC is a mung bean susceptible to the mung bean weevil. The breeding purpose of the method is to select mung beans susceptible to the mung bean weevil.

8. A DNA molecule, characterized by: The nucleotide sequence of the DNA molecule is sequence 3 in the sequence listing.

9. The use of the DNA molecule of claim 8 in any of the following: (1) To identify or assist in the identification of mung bean weevil resistance in mung beans; (2) Screening or breeding mung bean single plants, lines, strains or varieties resistant to mung bean weevil; (3) Screening or breeding mung bean single plants, lines, strains or varieties susceptible to mung bean weevil; (4) Prepare products for identifying or assisting in the identification of mung bean weevil resistance in mung beans; (5) Prepare or select mung bean single plants, lines, strains or varieties resistant to mung bean weevil; (6) Prepare products of single mung bean plants, lines, strains or varieties that are susceptible to mung bean weevil by screening or breeding.

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