CN113322343A

CN113322343A - Application of SNP molecular marker related to wheat powdery mildew resistance

Info

Publication number: CN113322343A
Application number: CN202110694662.3A
Authority: CN
Inventors: 吕亮杰; 陈希勇; 李辉; 赵爱菊; 刘玉平; 张业伦
Original assignee: Institute of Grain and Oil Crops of Hebei Academy of Agriculture and Forestry Sciences
Current assignee: Institute of Grain and Oil Crops of Hebei Academy of Agriculture and Forestry Sciences
Priority date: 2021-06-22
Filing date: 2021-06-22
Publication date: 2021-08-31
Also published as: CN113584215A; CN113584215B

Abstract

The invention discloses a method for identifying or assisting in identifying wheat powdery mildew resistance, application of a substance for detecting SNP molecular markers related to wheat powdery mildew resistance and a product. The method comprises the following steps: detecting the genotype of the wheat to be detected, and identifying or assisting in identifying the wheat powdery mildew resistance according to the genotype of the wheat to be detected; the genotype is CC genotype, AA genotype or CA genotype; the CC genotype represents that the nucleotide type of the KASP-7015 site in the wheat genome is homozygote of C; the AA genotype represents that the nucleotide type of KASP _7015 locus in the wheat genome is homozygous for A; the CA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is a heterozygous type of C and A; KASP _7015 is a SNP site in wheat genome located on chromosome 5A of wheat at nucleotide 101 of SEQ ID No. 4. Experiments prove that the powdery mildew resistance of the wheat variety with the KASP _7015 site AA genotype is lower than that of the wheat variety with the KASP _7015 site CC genotype, which shows that the KASP _7015 site is an SNP molecular marker related to the wheat powdery mildew resistance.

Description

Application of SNP molecular marker related to wheat powdery mildew resistance

Technical Field

The invention relates to the technical field of biology, in particular to application of SNP molecular markers related to wheat powdery mildew resistance.

Background

Wheat (Triticum aestivum) is one of the most important grain crops in China, and has a cultivation history for over ten thousand years in China (Jiang 36191, Wang Xiutong, China wheat industry development status problems and strategies shallow analysis [ J ] southern agriculture 2020, v.14; No.329 (31): 35-38.). As the largest wheat producing and consuming countries all over the world, the wheat yield in China reaches 13359 ten thousand tons and the planting area reaches 2373 thousand hectares by 2019 (the announcement of the food yield data in 2019 by the State statistics bureau, http:// www.stats.gov, cn/tjsi/zxfb/201912/t20191206_1715827. html). Therefore, stabilizing and improving the grain yield are the primary tasks for ensuring the basic life of the national people in China.

Powdery mildew is one of the main diseases of wheat production, and the wheat yield can be reduced by 20% in severe disease-affected areas, thus seriously threatening the yield and quality of wheat in China. The breeding of wheat powdery mildew resistant varieties is an efficient, green and sustainable approach for solving the problem. Breeding of varieties by molecular Marker-assisted Selection (MAS) has also become the mainstream, which remedies many disadvantages in traditional breeding and becomes an effective method for breeding resistant varieties with high efficiency (Tanksley et al, RFLPmapping in plant breeding: New tools for an old science.1989, Biotechnology, 7: 257-.

To date, more than 100 wheat powdery mildew resistance genes are found, 60 of which have been named (Pm1-Pm 62). Wherein, genes such as Pm6, Pm4a, Pm16 and the like develop corresponding SSR or InDel molecular markers for molecular marker-assisted selective breeding (Zhoujun, Xuhong, Xixin, and the like, wheat powdery mildew resistance and molecular marker research progress [ J ] Hubei agricultural science, 2020, v.59; No.651 (06): 12-17.). The molecular marker-assisted selection by using a high-throughput molecular detection platform is an effective means for increasing the yield breeding accuracy and improving the breeding efficiency. Single-nucleotide polymorphism (SNP) refers to DNA sequence polymorphism at the genome level caused by variation at the Single nucleotide level in a genome nucleotide sequence (Tang Liang Tu et al, research on SNP molecular markers and their application progress 2012, Chinese agricultural bulletin 28 (12): 154-158.). The marker designed based on the SNP locus is a third-generation molecular marker developed on the basis, and the marker type has low mutation frequency and high genetic stability; the loci are rich and the distribution is wide; rapid detection, large-scale screening and the like. Compared with the first generation and the second generation molecular markers, the KASP marker designed based on the SNP locus does not need to be typed according to the size of a DNA fragment, and can get rid of the detection method of the traditional gel electrophoresis, which has the relatively complicated steps, low throughput and higher price. Therefore, the method is more suitable for the high-flux molecular detection platform which is rapidly developed at the present stage.

Although many of the above-mentioned linked markers of wheat powdery mildew resistance related genes can be used for molecular marker-assisted selection, most of them are SSR markers, InDel markers or enzyme digestion markers, and the detection efficiency is low, and at the same time, aerosol may be generated to pollute the environment, and the method is not suitable for a high-throughput molecular detection platform. Therefore, the development of the wheat powdery mildew resistance KASP molecular marker suitable for a high-throughput molecular detection platform has important significance for popularizing the application of the molecular marker technology and improving the wheat powdery mildew resistance breeding efficiency and level in China.

Disclosure of Invention

The invention provides a method for identifying or assisting in identifying wheat powdery mildew resistance, which comprises the steps of detecting the genotype of wheat to be detected, and identifying or assisting in identifying the wheat powdery mildew resistance according to the genotype of the wheat to be detected; the genotype is CC genotype, AA genotype or CA genotype; the CC genotype represents that the nucleotide type of the KASP-7015 locus in the wheat genome is homozygote of C; the AA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is homozygous for A; the CA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is a heterozygous type of C and A; the KASP _7015 site is one SNP site in wheat genome and is located in the 101 st nucleotide of SEQ ID No.4 in the 5A chromosome of wheat, and the nucleotide is A or C. The genotype of the KASP _7015 site is AA genotype, and the powdery mildew resistance of the wheat to be detected is lower than or is candidate to be lower than that of the wheat to be detected of which the genotype of the KASP _7015 site is CA genotype or CC genotype.

The application of the method in wheat breeding also belongs to the protection scope of the invention.

The invention also provides application of the substance for detecting the polymorphism or genotype of the KASP _7015 locus. The application is the application in identifying or assisting in identifying the wheat powdery mildew resistance, the application in preparing products for identifying or assisting in identifying the wheat powdery mildew resistance or the application in wheat assisted breeding or preparing products for wheat assisted breeding.

The invention also provides a wheat breeding method, which comprises selecting wheat with the genotype of the KASP _7015 locus being AA or CA as a parent to breed, wherein the AA genotype represents that the nucleotide species of the KASP _7015 locus in a wheat genome is homozygous for A; the CA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is a heterozygous type of A and C.

In the above, the wheat breeding may be breeding of a wheat variety resistant to powdery mildew. The powdery mildew resistance in the powdery mildew resistant wheat variety is relative to a hybrid parent wheat. The powdery mildew resistance of said powdery mildew resistant wheat variety may be equal to or higher than the powdery mildew resistance of the hybrid parent wheat if the resistance to powdery mildew of the two hybrid parent wheat is the same; if the resistance of the two hybrid parent wheat to powdery mildew is not the same, the powdery mildew resistance of the powdery mildew resistant wheat variety can be equal to or higher than that of the hybrid parent wheat with lower powdery mildew resistance in the two hybrid parent wheat.

Products containing the substance for detecting the polymorphism or genotype of KASP _7015 site are also within the scope of the present invention.

The product is any one of C1) -C3):

C1) products for detecting single nucleotide polymorphisms or genotypes associated with wheat powdery mildew resistance;

C2) identifying or assisting in identifying wheat powdery mildew resistant products;

C3) the product is used for wheat auxiliary breeding.

Above, the substance for detecting a polymorphism or genotype of KASP 7015 site may be D1), D2), or D3) as follows:

D1) the substance for detecting the polymorphism or genotype of the KASP _7015 site contains a PCR primer for amplifying a wheat genome DNA fragment including the KASP _7015 site;

D2) the substance for detecting the polymorphism or the genotype of the KASP _7015 locus is a PCR reagent containing the PCR primer;

D3) a kit containing the PCR primer described in D1) or the PCR reagent described in D2).

As described above, the PCR primer may be a primer set consisting of a single-stranded DNA whose nucleotide sequence is the 22 nd to 44 th positions of SEQ ID No.1 of the sequence Listing, a single-stranded DNA whose nucleotide sequence is the 22 nd to 44 th positions of SEQ ID No.2 of the sequence Listing, and a single-stranded DNA whose nucleotide sequence is SEQ ID No.3 of the sequence Listing.

Optionally, the PCR primer is a primer group consisting of a single-stranded DNA shown by SEQ ID No.1 in the sequence table, a single-stranded DNA shown by SEQ ID No.2 in the sequence table and a single-stranded DNA shown by SEQ ID No.3 in the sequence table.

In the above applications, methods and products, the PCR primers may or may not be labeled with a label. The label refers to any atom or molecule that can be used to provide a detectable effect and that can be attached to a nucleic acid. Labels include, but are not limited to, dyes; radiolabels, e.g.³²p; binding moieties such as biotin (biotin); haptens such as Digoxin (DIG); a luminescent, phosphorescent, or fluorescent moiety; and a fluorescent dye alone or in combination with a portion of the emission spectrum that can be suppressed or shifted by Fluorescence Resonance Energy Transfer (FRET). Labels can provide signals detectable by fluorescence, radioactivity, colorimetry, gravimetry, X-ray diffraction or absorption, magnetism, enzymatic activity, and the like. Labels can be charged moieties (positive or negative) or alternatively, can be charge neutral. The label may comprise or be combined with a nucleic acid or protein sequence, provided that the sequence comprising the label is detectableIn (1). In some embodiments, the nucleic acid is detected directly (e.g., direct sequence read) without a label.

The invention provides development and application of an SNP molecular marker tightly linked with a wheat powdery mildew resistance related gene PmCH7015, wherein the molecular marker is an SNP molecular marker KASP _7015 tightly linked with the wheat powdery mildew resistance related gene PmCH 7015. The molecular marker can detect 527492344 th base of 5A chromosome of wheat genome in high flux. The method provided by the invention is used for carrying out genotype identification on the SNP molecular marker closely linked with the wheat powdery mildew resistance related gene PmCH7015, for example, a KASP technology is applied, the method has the advantages of simple and convenient operation, low cost, short detection period, stable marker, environmental protection and the like, can accurately detect the wheat powdery mildew resistance related gene PmCH7015, and has important significance for promoting wheat yield breeding.

In one embodiment of the invention, the KASP technique is used to identify the genotype of the KASP _7015 locus in 8 wheat varieties. Experiments prove that the phenotype of the homozygous wheat variety with the KASP _7015 site as C is powdery mildew resistance, the phenotype of the homozygous wheat variety with the KASP _7015 site as A is powdery mildew susceptibility, and the KASP _7015 site is an SNP molecular marker related to wheat powdery mildew resistance, can be used for identifying or assisting in identifying wheat powdery mildew resistance, can be used for screening wheat powdery mildew resistance varieties, and can be used for wheat molecular marker assisted breeding. The polymorphism of KASP _7015 site is directly expressed in the form of DNA and can be detected in each tissue and each development stage of wheat, which is favorable for conveniently and rapidly predicting wheat powdery mildew resistance. In practical application, in order to improve the accuracy, the substance for detecting KASP _7015 site polymorphism and genotype can be combined with other substances (such as substances for detecting other single nucleotide polymorphism or genotype related to wheat powdery mildew resistance) to prepare a product for identifying wheat powdery mildew resistance.

Drawings

FIG. 1 is a graph showing the genotyping of 8 wheat cultivars tested using the molecular marker KASP-7015 in example 1, wherein CC-FAM indicates genotype CC and AA-VIC indicates genotype AA.

FIG. 2 is a chart showing the typing of the F2 isolate population in example 2 using the molecular marker KASP _7015, in which CC-FAM indicates the genotype CC, AA-VIC indicates the genotype AA, and A/C indicates the genotype AC.

Detailed Description

The present invention is described in further detail below with reference to specific embodiments, which are given for the purpose of illustration only and are not intended to limit the scope of the invention. The examples provided below serve as a guide for further modifications by a person skilled in the art and do not constitute a limitation of the invention in any way.

The experimental procedures in the following examples, unless otherwise indicated, are conventional and are carried out according to the techniques or conditions described in the literature in the field or according to the instructions of the products. Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

The wheat varieties used in the examples described below are commercially available.

The present inventors selected a SNP site related to resistance to wheat powdery mildew, which is closely linked to the PmCH7015 gene and anchored at position 527492344 (http:// plants. ensembles. org/index. html, genome version Triticum aestivum IWGSC (Genomic sequence)) on chromosome 5A of wheat, and named this SNP site as KASP _7015, whose flanking sequence is shown in SEQ ID No.4, where m is a or c in SEQ ID No. 4. KASP _7015 is located at position 101 of SEQ ID No.4 where the nucleotide species is A or C.

The following CC genotypes indicate that the nucleotide species of KASP _7015 is homozygous for C; the AA genotype indicates that the nucleotide type of KASP _7015 is homozygous for A; the CA genotype indicates that the nucleotide class of KASP _7015 is a heterozygous for A and C.

Example 1 development of KASP marker closely linked to wheat powdery mildew resistance-related Gene PmCH7015

1. Designing a primer: the Primer5.0 software was used to design 3 sets of KASP primers for the tightly linked molecular marker Xgpw4079 (described in Guo Huiyan, Jia Bo Qing, Lixin, etc. SSR mapping of powdery mildew resistant genes in wheat germplasm CH7015 [ J ]. North China agro-Proc, 2019, 34 (6): 203-. After detection using the ArrayTape platform from Douglas Scientific, 1 set of KASP primers with good polymorphism was selected for subsequent validation.

The KASP primers used to detect KASP — 7015 are specifically as follows:

primer X: 5'-gaaggtcggagtcaacggattGGGCTCTCTAGTTCGTCTGTCAA-3' (SEQ ID No.1, lower case letter portion is specific fluorescent tag sequence VIC);

primer Y: 5'-gaaggtgaccaagttcatgctGGGCTCTCTAGTTCGTCTGTCAC-3' (SEQ ID No.2, lower case letter portion is specific fluorescent tag sequence FAM);

Primer R：5’-AGTTCGGACTACGAGCATTAGAGAT-3’(SEQ ID No.3)。

DNA extraction: extracting genome DNA from wheat leaves by a conventional CTAB method.

KASP reaction test

SNP marker amplification and reaction system:

(1) and (3) detecting by using a fluorescent quantitative PCR instrument AB-Q6 Flex:

the detection reaction system of the 5-mu-L PCR fluorescence quantitative instrument comprises: 50ng of genomic DNA, and 0.07. mu.L of a Primer mixture (preferably, the ratio of the Primer mixture is 100 pmol. multidot.L for the forward primers Primer X and Primer Y)^-112. mu.L each, reverse Primer R100 pmol. multidot.L^-130μL，ddH₂O46. mu.L, which can achieve the same detection purpose by using other reasonable primer mixture ratios), 2.5. mu.L of LGC company 2 XKASP Mix (Low Rox). Editing a sample table, executing a running program and storing data according to an AB-Q6 instrument operation manual of the fluorescent quantitative PCR instrument.

The above reaction system is the preferred reaction system of AB-Q6 Flex, and other reasonable reaction systems can also achieve the same detection purpose.

(2) The selection of the ArrayTape platform from Douglas Scientific

1.6 u L PCR ArrayTape platform detection reaction system includes: genomic DNA 50 ng/. mu.L 0.8. mu.L, Primer mix 0.03. mu.L (preferred Primer mix ratio: forward primers Primer X, Primer Y100 pmol. L)^-112 μ L each, reverse Primer R100pmol·L^-130μL，ddH₂O46. mu.L, which can achieve the same detection object by using other reasonable primer mixture ratios), LGC 2 XKASP Mix (Std Rox) 0.8. mu.L. According to an ArrayTape platform instrument operation manual, a sample table is compiled, a program is operated, and data are read.

The above reaction system is the preferable reaction system of the ArrayTape platform of Douglas Scientific company, and other reasonable reaction systems can achieve the same detection purpose.

Note: the above is a recommended detection method, and other detection methods capable of achieving the same detection purpose can also be applied to the molecular marker-assisted breeding process of the marker.

Wherein, the 2 XKASP Mix consists of a fluorescent probe A, a fluorescent probe B, a quenching probe A and a quenching probe B, high fidelity Taq enzyme, dNTP and Mg²⁺And the like. The nucleotide sequence of the fluorescent probe A is as follows: 5'-GAAGGTCGGAGTCAACGGATT-3', connecting a VIC fluorescent group at the 5 ' end; the nucleotide sequence of the fluorescent probe B is as follows: 5'-GAAGGTGACCAAGTTCATGCT-3', wherein the 5 ' end is connected with a FAM fluorescent group; the nucleotide sequence of the quenching probe A is as follows: 5'-AATCCGTTGACTCCGACCTTC-3', wherein the 3 ' end is connected with a quenching group BHQ; the nucleotide sequence of the quenching probe B is as follows: 5'-AGCATGAACTTGGTCACCTTC-3', wherein the 3 ' end is connected with a quenching group BHQ.

And (3) amplification procedure: pre-denaturation at 95 ℃ for 10min for 1 cycle; denaturation at 95 ℃ for 20s, annealing at 55-62 ℃ (preferably 55 ℃) for 60s, setting 40 cycles.

The experiment was carried out while setting a blank control (NTC) without adding template DNA to the reaction system, and 1 or more blank controls were set for each plate.

Analyzing the scanning data, and then determining the genotype of the KASP _7015 locus in the wheat genome to be detected (namely, detecting whether the 527492344 th base of the chromosome 5A of the wheat genome is A or C), wherein if the fluorescence signal data of the amplification product of the wheat to be detected is analyzed to be close to the X axis (VIC signal) by Douglas genotyping software, the genotype of the KASP _7015 locus in the wheat genome to be detected is AA homozygous (namely, the 527492344 th base of the chromosome 5A of the wheat genome is AA homozygous); if the fluorescence signal data of the amplification product of the wheat to be detected is analyzed to be close to a Y axis (FAM signal) by Douglas genotyping software, the genotype of the KASP-7015 locus in the wheat genome to be detected is CC homozygote (namely the 527492344 th base of the chromosome 5A of the wheat genome is CC homozygote); if the fluorescence signal data of the amplification product of the wheat to be detected is positioned between an X axis and a Y axis (VIC and FAM signals) through analysis of Douglas genotyping software, the genotype of the KASP _7015 site in the wheat genome to be detected is a CA heterozygous type (namely, the 527492344 th base of the 5A chromosome of the wheat genome is the CA heterozygous type). The samples shown black in the lower left corner are blank controls.

5. Label typing data analysis

To verify the reliability of KASP _7015 markers, 8 wheat cultivar materials of table 1 were first subjected to molecular marker detection using KASP _7015 (fig. 1); then, 8 parts of wheat variety materials are inoculated and identified for powdery mildew, resistance data of the materials to the powdery mildew are obtained, and the powdery mildew inoculation identification method and evaluation standards are shown in documents (Guo Huiyan, Jia Woqing, Lixin, and the like. SSR positioning of powdery mildew resistant genes in wheat germplasm CH7015 [ J ]. North China agricultural science, 2019, 34 (6): 203-. The genotype of the material was detected using the ArrayTape platform from Douglas Scientific, and the experimental design was repeated 2 times to ensure accuracy. The amplification results are shown in Table 1 and show that the KASP _7015 marker enables stable PCR products to be obtained in 8 materials and that both the A-VIC and C-FAM allelic sites can be detected (FIG. 1). Through the consistency analysis of the KASP marker and the identification result of the powdery mildew resistance phenotype, only one of 8 materials has a material resistance result difference.

Therefore, the KASP _7015 marker of the invention can be used for molecular marker assisted breeding of the wheat powdery mildew resistance gene pmCH 7015.

TABLE 1.8 phenotypic and genotypic information for test wheat varieties

Note: in the table, "R" indicates that the phenotype of the material is disease-resistant; "S" indicates that the phenotype of the material is susceptible; "CC" means CC homozygous for; "AA" means AA homozygous; "CA" means CA heterozygous; "+" indicates no detection signal.

Example 2 application of KASP marker closely linked to wheat powdery mildew resistance related gene PmCH7015 in molecular marker assisted selection of wheat powdery mildew resistant plants

To test the utility of the KASP _7015 marker of the present invention, wheat variety materials Yangmai No. 12 (Daihua Daihuayu group Co., Ltd., Jiangsu province) and CH7015 (described in Guo Hui Juan, Jia Zhuoqing, Lixin, etc.. SSR location of powdery mildew resistance gene in wheat germplasm CH7015 [ J ]. North China agro Proc., 2019, 34 (6): 203:. 208.), F1 population was produced by hybridization, F2 isolate population 90 was produced by selfing, KASP marker detection and disease-resistant phenotype verification were performed on the isolate (Table 2), and the marker detection and disease-resistant phenotype verification were performed with reference to example 1 (FIG. 2). Among them, 90 wheat powdery mildew inoculation identification method and evaluation standard are disclosed in literature (Guo Huiyan, Jia Woqing, Li Xin, etc. SSR localization of powdery mildew resistant gene in wheat germplasm CH7015 [ J ] North China agricultural science, 2019, 34 (6): 203-.

By phenotypic and genotypic testing and analysis of the segregating population, only 6 of the 90 segregating population individuals had genotypic and phenotypic results which were inconsistent, with the consistency of the marker KASP _7015 with field resistance being 93.33%. Among 90F 2 generation plants, 20 plants have the genotype of KASP _7015 locus of CC, and the powdery mildew resistance is R; there were 47 strains with a genotype at the KASP — 7015 site that was CA, where the powdery mildew resistance of 44 strains was R and the powdery mildew resistance of 3 strains was S; there were 23 strains with a genotype at the KASP — 7015 site that was AA, 20 strains with all S powdery mildew resistance and 3 strains with R powdery mildew resistance. The mark KASP _7015 has higher practicability in screening wheat root-knot nematode resistant plants.

TABLE 2 phenotype of wheat segregating population and genotype information at KASP _7015 site

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

The present invention has been described in detail above. It will be apparent to those skilled in the art that the invention can be practiced in a wide range of equivalent parameters, concentrations, and conditions without departing from the spirit and scope of the invention and without undue experimentation. While the invention has been described with reference to specific embodiments, it will be appreciated that the invention can be further modified. In general, this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. The use of some of the essential features is possible within the scope of the claims attached below.

Sequence listing

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Claims

1. Application of a substance for detecting polymorphism or genotype of KASP _7015 site in identification or auxiliary identification of wheat powdery mildew resistance, wherein the KASP _7015 site is an SNP site in a wheat genome, is positioned at 101 st nucleotide of SEQ ID No.4 on a wheat No. 5A chromosome, and has the nucleotide type of A or C.

2. Use of a substance described in claim 1 for detecting polymorphisms or genotypes at the KASP _7015 locus for the preparation of a product for identifying or aiding in the identification of wheat powdery mildew resistance.

3. The use of a substance for detecting polymorphisms or genotypes at the KASP _7015 locus as claimed in claim 1 in wheat assisted breeding or in the preparation of wheat assisted breeding products.

4. The method for identifying or assisting in identifying wheat powdery mildew resistance is characterized by comprising the following steps of: detecting the genotype of wheat to be detected, and identifying or assisting in identifying the wheat powdery mildew resistance according to the genotype of the wheat to be detected; the genotype is CC genotype, AA genotype or CA genotype; (ii) a The CC genotype represents that the nucleotide type of the KASP-7015 locus in the wheat genome is homozygote of C; the AA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is homozygous for A; the CA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is a heterozygous type of C and A; the KASP _7015 site is one SNP site in wheat genome and is located in the 101 st nucleotide of SEQ ID No.4 in the 5A chromosome of wheat, and the nucleotide is A or C.

5. Use of the method of claim 4 in wheat breeding.

6. A method for breeding wheat, which comprises selecting wheat as a parent, wherein the genotype of KASP _7015 locus in claim 4 is AA or CA, and the AA genotype represents the homozygous type of the nucleotide type A at KASP _7015 locus in the wheat genome; the CA genotype represents that the nucleotide type of the KASP _7015 site in the wheat genome is a heterozygous type of A and C.

7. The product containing the substance for detecting the polymorphism or genotype of KASP _7015 site as claimed in claim 1 is any one of C1) -C3):

C3) the product is used for wheat auxiliary breeding.

8. Use according to any one of claims 1 to 3 or a product according to claim 7, wherein: the substance for detecting a polymorphism or genotype at KASP _7015 site according to claim 1, which is D1), D2) or D3) as follows:

9. Use or product according to claim 8, characterized in that: the PCR primer is a primer group consisting of single-stranded DNA with a nucleotide sequence of 22 th to 44 th positions of SEQ ID No.1 in a sequence table, single-stranded DNA with a nucleotide sequence of 22 nd to 44 th positions of SEQ ID No.2 in the sequence table and single-stranded DNA with a nucleotide sequence of SEQ ID No.3 in the sequence table.

10. Use or product according to claim 8 or 9, characterized in that: the PCR primer is a primer group consisting of a single-stranded DNA shown by SEQ ID No.1 in a sequence table, a single-stranded DNA shown by SEQ ID No.2 in the sequence table and a single-stranded DNA shown by SEQ ID No.3 in the sequence table.