Cereal broad-spectrum disease and insect resistance functional major gene, linked molecular marker and dual application system of molecular design breeding

Abstract

The application discloses a kind of broad-spectrum disease and insect resistance functional major genes of cereal, linkage molecular marker and dual application system of molecular design breeding, belong to crop molecular genetic breeding technical field.The core of the system is broad-spectrum disease and insect resistance major gene Bsdr1 and its excellent haplotype, the gene can mediate the broad-spectrum dominant resistance of multiple diseases and multiple insect pests of cereal crops, and is conserved in function in cereal crops.The present application develops two types of linkage molecular markers, co-dominant InDel and KASP, with a genetic distance of less than 0.5 cM, and the accuracy of genotype selection is over 98%.The system includes two independent and linked modules of functional gene directed improvement and molecular marker assisted breeding, covering the whole process of germplasm creation and variety improvement.The present application solves the pain points of existing technology, such as narrow resistance spectrum, low marker accuracy, research and application disconnection, and long breeding cycle, can greatly shorten the breeding cycle, improve the efficiency of disease and insect resistance breeding, reduce pesticide application, and has important economic and ecological value.

Description

Technical Field

[0001] This invention belongs to the field of crop molecular genetics breeding and plant biotechnology, and in particular relates to a dual application system of major functional genes for broad-spectrum disease and pest resistance in cereals, linked molecular markers, and molecular design breeding. Background Technology

[0002] Cereal crops are my country's largest grain crop category, accounting for over 90% of the country's total grain output. Their stable yield is directly related to national food security. Pests and diseases are the core biological stressors restricting the yield and quality of cereal crops. Annual yield losses due to diseases and pests reach 10% to 30% of total yield, and in years with severe pest infestations, yield reductions in some areas can exceed 50%. Traditional chemical control methods not only increase agricultural production costs but also easily lead to a series of problems such as pesticide residues, environmental pollution, and increased pesticide resistance in pests and diseases. Developing pest- and disease-resistant crop varieties is currently recognized as the most economical, green, and safe approach to pest and disease control.

[0003] Current disease and insect resistance breeding technologies still suffer from three significant shortcomings: First, there is a scarcity of broad-spectrum major-effect gene resources. Most cloned disease and insect resistance genes are specialized resistance genes, capable of resisting only a single disease or insect, or a few physiological races / biotypes. They are easily lost due to pathogen variation and insect biotype evolution, resulting in poor resistance persistence. Furthermore, the number of broad-spectrum major-effect genes possessing both disease and insect resistance is extremely limited, failing to meet the breeding needs of areas with multiple disease and insect outbreaks. Second, there is a lack of practical molecular markers. Most developed disease and insect resistance linkage markers have a large genetic distance from the target gene, typically greater than 2 cM, resulting in genotype selection accuracy below 90%. Moreover, most are dominant markers, lacking practical molecular markers. The lack of markers suitable for high-throughput automated detection makes it difficult to support large-scale commercial breeding applications. Third, there is a disconnect between gene research and breeding applications. Existing technologies mostly focus on the functional mechanism analysis of genes, lacking standardized supporting technologies for breeding applications, or only developing markers for auxiliary selection without in-depth exploration and targeted modification of gene functions. An integrated application system covering the entire process from germplasm innovation to variety improvement has not yet been formed. The cycle from discovery to industrial application of gene resources is as long as 8 to 10 years, with low conversion efficiency and a single breeding path that cannot simultaneously adapt to the technical conditions and regulatory requirements of different breeding entities. Summary of the Invention

[0004] This invention addresses the shortcomings of existing technologies by solving three core technical problems: first, the narrow spectrum of disease and pest resistance genes in cereals, insufficient resources of major-effect broad-spectrum genes, and poor resistance persistence; second, the problems of weak linkage between existing molecular markers and target genes, low selection accuracy, and insufficient detection throughput; and third, the problems of the disconnect between gene function research and breeding applications, the lack of an integrated application system, long breeding cycles, and limited applicable scenarios.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] This invention provides a dual-application system for molecular design breeding of broad-spectrum disease and pest resistance in cereals, including the major functional gene Bsdr1 with broad-spectrum disease and pest resistance, a set of codominant molecular markers closely linked to Bsdr1, a functional gene-directed improvement module, and a molecular marker-assisted breeding module.

[0007] Bsdr1 is a gene encoding a cell membrane localization pattern recognition receptor naturally present in cereal crops. It activates the plant MAPK basic immune pathway by recognizing molecular patterns related to pathogenic fungi and insect feeding, upregulates the expression of phytoalexin synthesis genes and insect feeding inhibitory protein genes, and simultaneously regulates the accumulation of reactive oxygen species and callose deposition. It mediates broad-spectrum dominant resistance to a variety of fungal diseases and agricultural pests from both physical barrier and chemical defense perspectives. This gene is a dominant major-effect gene, contributing 35% to 50% to the phenotype of resistance to diseases and pests. The first generation of hybrids can show significant resistance, which is suitable for the breeding needs of hybrid cereal crops.

[0008] Furthermore, the resistance spectrum mediated by the Bsdr1 gene covers at least three or more of the following fungal diseases: rice blast, rice sheath blight, wheat stripe rust, wheat powdery mildew, maize large leaf spot, and maize small leaf spot; and two or more of the following agricultural pests: rice brown planthopper, rice stem borer, wheat long-tubed aphid, and maize borer.

[0009] Furthermore, the Bsdr1 gene contains the superior haplotype Bsdr1-Hap1; the promoter region of the superior haplotype contains natural expression regulatory variations, which upregulate the gene expression level by 2 to 3 times compared with the common haplotype in cultivated varieties, and correspondingly improve the disease and pest resistance level of crops by 2 to 3 levels, which is the core superior variation for breeding utilization.

[0010] Furthermore, the Bsdr1 gene has functional homologous genes in the collinear regions of homologous chromosomes of rice, wheat, and maize, and exhibits conservation of broad-spectrum disease and pest resistance in cereal crops.

[0011] The codominant molecular marker set was developed based on natural insertion / deletion polymorphism sites on the flanking genome of the Bsdr1 gene. The genetic distance from the Bsdr1 gene is less than 0.5 cM, and the physical distance is less than 80 kb. The marker genotype and the disease-resistant phenotype co-segregate. The molecular marker set can distinguish between homozygous disease-resistant, heterozygous, and homozygous disease-susceptible genotypes. The phenotypic selection accuracy is ≥98% in the segregating population and phenotypic concordance rate is ≥97% in the natural germplasm population.

[0012] Furthermore, the codominant molecular marker set includes Bsdr1-InDel1 markers and Bsdr1-K1 markers;

[0013] Bsdr1-InDel1 is a common PCR-InDel marker, and the genotype is determined by gel electrophoresis, making it suitable for testing in small and medium-sized breeding populations.

[0014] The Bsdr1-K1 is a high-throughput KASP fluorescent marker that uses fluorescence signals to determine genotype and is compatible with automated high-throughput detection platforms for 96 / 384-well plates.

[0015] The functional gene-directed improvement module is used to create broad-spectrum disease and insect resistant germplasm materials by mining natural superior variations of Bsdr1 or by directionally regulating the gene function of Bsdr1, and includes three independently implementable technical approaches:

[0016] 1. Natural superior allelic variation screening path: Using the Bsdr1 haplotype detection marker, high-throughput screening is carried out in cereal germplasm resource banks, local varieties or wild closely related populations to identify germplasm materials carrying the superior haplotype Bsdr1-Hap1, which can be directly used as disease and pest resistance breeding donors.

[0017] 2. Endogenous gene targeted editing pathway: Using gene editing technology, the negative regulatory cis-acting elements in the promoter region of the endogenous Bsdr1 gene in the recipient crop are precisely knocked out, or key negative regulatory sites in the coding region are replaced at specific points. Without introducing exogenous genes, the gene expression level or protein activity of Bsdr1 is enhanced, thereby directionally improving the broad-spectrum disease and pest resistance of the recipient crop.

[0018] 3. Gene overexpression enhancement pathway: Construct plant expression vectors carrying the superior allele of Bsdr1-Hap1, and carry out genetic transformation through Agrobacterium-mediated transformation or gene gun method to obtain Bsdr1 gene overexpression lines, and create high-resistance broad-spectrum disease and insect resistant germplasm materials.

[0019] The molecular marker-assisted breeding module is used to conduct precise genotyping using the codominant molecular marker set, achieving efficient transfer and multi-gene aggregation of disease and pest resistance traits, and includes three independently implementable application processes:

[0020] 1. Marker-assisted backcross breeding process: Using materials carrying the superior Bsdr1 allele as donors and the main cultivated variety as recurrent parents, foreground selection is performed in each backcross generation using the codominant molecular marker set to screen for single plants carrying the target gene; at the same time, background selection is performed using whole-genome molecular markers to screen for single plants with the highest genome reversion rate to enter the next generation, and to rapidly breed disease- and insect-resistant near-isogenic lines with pure genetic background;

[0021] 2. Multi-gene aggregation breeding process: Combine the codominant molecular marker of Bsdr1 with linkage markers of other disease-resistant, insect-resistant, high-yielding, and superior trait genes to establish a multi-gene molecular detection system; simultaneously perform multi-gene genotypic selection in the hybrid segregating generation to rapidly aggregate multiple beneficial genes and cultivate durable resistant varieties with excellent comprehensive traits.

[0022] 3. Early generation joint selection process: During the early generation seedling stage of hybridization, prospect selection and whole genome background screening of the Bsdr1 target gene are carried out simultaneously to eliminate non-target plants in advance and reduce the population size for subsequent field planting and phenotypic identification.

[0023] The functional gene-directed improvement module and the molecular marker-assisted breeding module can be implemented independently or in conjunction. The implementation method of the conjunction is as follows: first, the functional gene-directed improvement module creates core donor germplasm carrying the superior Bsdr1 allele, and then the molecular marker-assisted breeding module transfers the target gene into the main cultivated varieties in different ecological zones, so as to realize the integrated promotion of germplasm innovation, variety improvement and industrial application, covering the entire breeding process from germplasm innovation to variety cultivation.

[0024] The beneficial effects of the present invention after adopting the above structure are as follows:

[0025] (1) The Bsdr1 identified in this invention is a major broad-spectrum gene that simultaneously mediates disease resistance and insect resistance, breaking through the limitation of narrow resistance spectrum of single genes; the basic immune resistance it mediates is non-specific resistance, which is not easily overcome by pathogens or pests, and the resistance persistence is significantly better than traditional specific resistance genes, which can effectively extend the field use life of crop varieties.

[0026] (2) The codominant molecular marker developed in this invention is closely linked to the target gene, with an accuracy rate of ≥98%. It can be detected non-destructively during the seedling stage without the need for artificial insect or bacterial inoculation and is not affected by environmental conditions. At the same time, it provides two types of markers: ordinary gel type and high-throughput type, which are suitable for the detection conditions and scale requirements of different entities such as scientific research units and seed companies.

[0027] (3) This system covers both genetic engineering improvement and conventional molecular breeding. It can rapidly improve the main varieties through gene editing and conduct conventional breeding through marker-assisted selection, adapting to different regulatory requirements and breeding objectives. The system has a high degree of standardization and can be directly embedded into commercial breeding processes, shortening the breeding cycle of disease-resistant varieties from the traditional 6-8 years to 2-3 years, and improving the overall breeding efficiency by more than 3 times.

[0028] (4) The application of the disease and pest resistant varieties bred by this system can reduce the amount of pesticides used in the field by 30% to 50%, reduce agricultural production costs, reduce pesticide residues and environmental pollution, which is in line with the development of green agriculture and the national food security strategy, and has significant economic, ecological and social benefits. Attached Figure Description

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0030] Figure 1 Chromosomal localization and linkage molecular marker map of the Bsdr1 gene;

[0031] Figure 2 A dual-application system architecture diagram for molecular design breeding of broad-spectrum disease and pest resistance in cereals. Detailed Implementation

[0032] Example 1: Localization of the Bsdr1 gene and verification of its broad-spectrum disease and insect resistance function.

[0033] 1. Test materials

[0034] The donor material was the common wild rice germplasm RW12, which, after years of multi-location phenotypic identification, was found to be highly resistant to rice blast, sheath blight, and brown planthopper, and carried the superior haplotype Bsdr1-Hap1. The recipient material was the main cultivated japonica rice variety Kongyu 131, which was susceptible to rice blast, sheath blight, and brown planthopper, and did not contain the Bsdr1-Hap1 haplotype. The target population consisted of 2800 F2 segregating plants constructed with RW12 as the male parent and Kongyu 131 as the female parent, as well as the corresponding F2:3 families.

[0035] 2. Fine gene mapping and genetic effect analysis

[0036] Using bipolar segregation analysis (BSA) combined with linkage mapping, the major QTL controlling broad-spectrum disease and pest resistance was located on the short arm of rice chromosome 6, named qBsdr6-1, with the corresponding functional gene being Bsdr1. Genetic effect analysis showed that this locus contributed 42.3% to rice blast resistance, 38.7% to sheath blight resistance, and 36.9% to brown planthopper resistance, consistent with the genetic characteristics of a major gene. Through expanded segregating populations for fine mapping, Bsdr1 was ultimately pinpointed to a 72kb physical region. Expression association analysis and transgenic function verification confirmed that the gene encoding the membrane localization pattern recognition receptor was the target gene, Bsdr1.

[0037] 3. Validation of broad-spectrum resistance phenotype

[0038] Using the near-isogenic line NIL-Bsdr1 of Bsdr1 with a genetic background of Kongyu 131 and a wild-type control as materials, resistance to multiple diseases and insect pests was identified:

[0039] Disease resistance assessment: After inoculation with 15 dominant physiological races of rice blast fungus, NIL-Bsdr1 showed moderate to high resistance to all races, with 12 races reaching high resistance, and an average disease severity grade of 2.1. The wild-type control was susceptible to all races, with an average disease severity grade of 7.3. After inoculation with rice sheath blight, the length of lesions in NIL-Bsdr1 was shortened by 62% compared to the control, indicating moderate resistance.

[0040] Insect resistance assessment: The brown planthopper resistance was assessed using the seedling group inoculation method. NIL-Bsdr1 showed a resistance level of 2 (highly resistant), while the control showed 9 (highly susceptible). The rice stem borer resistance was assessed using the in vitro stem inoculation method. Seven days after inoculation, the mortality rate of larvae on NIL-Bsdr1 was 68%, compared to only 12% in the control. These results demonstrate that Bsdr1 simultaneously confers significant resistance to multiple diseases and insect pests on rice, making it a broad-spectrum major gene for disease and insect resistance.

[0041] 4. Verification of functional conservation in cereal crops

[0042] Homologous genes of Bsdr1 were identified on wheat chromosome 2 and maize chromosome 1 through genome collinearity analysis. Association analysis of 260 core wheat germplasm accessions showed that materials carrying superior haplotypes of the wheat homologous gene exhibited an average reduction of 2.4 grades in stripe rust severity, 1.9 grades in powdery mildew severity, and a 57% reduction in wheat aphid population density compared to the control, demonstrating that this gene possesses a conserved broad-spectrum disease and pest resistance function in cereal crops.

[0043] Example 2: Development and accuracy verification of tightly linked co-dominant molecular markers

[0044] 1. Molecular marker development

[0045] Based on a 12bp insertion / deletion polymorphism at a position 25kb upstream of the Bsdr1 gene, a codominant InDel marker, named Bsdr1-InDel1, was designed. This marker amplified a long fragment in materials carrying the Bsdr1-Hap1 gene and a short fragment in susceptible allelic materials. Heterozygous materials showed both bands simultaneously, directly distinguishing between homozygous resistant, heterozygous, and homozygous susceptible genotypes. This polymorphism was further converted into a KASP high-throughput marker, named Bsdr1-K1, which automatically interprets genotypes using fluorescence signals, making it compatible with high-throughput detection platforms.

[0046] 2. Labeling accuracy verification

[0047] The marker genotype was detected in a segregating F2 population of 2800 plants, and field identification of disease and pest resistance phenotypes was conducted simultaneously. The results showed a 98.7% concordance rate between the marker genotype and the disease and pest resistance phenotype, with a genetic distance of 0.21 cM, indicating close linkage between the two. Validation was performed in 320 natural rice germplasm accessions, showing concordance rates of 97.8% and 98.1% between the marker genotype and the phenotypes for rice blast and brown planthopper, respectively. This demonstrates that the marker has high selection accuracy under different genetic backgrounds and can be stably used for molecular breeding.

[0048] Example 3: Implementation of the Functional Gene-Directed Improvement Module

[0049] This embodiment uses the endogenous gene-directed editing pathway as an example to create a highly resistant main cultivated variety. Using Nanjing 9108, a main cultivated japonica rice variety in the middle and lower reaches of the Yangtze River, as the recipient, CRISPR-Cas9 technology was used to precisely knock out the negative regulatory element of the promoter of its endogenous Bsdr1 gene.

[0050] Target design: sgRNAs were designed targeting the WRKY transcription factor negative regulatory binding site in the Bsdr1 promoter region to achieve site-specific deletion;

[0051] Material creation: T0 generation editing lines were obtained through Agrobacterium-mediated transformation, and homozygous editing lines without exogenous T-DNA insertion were obtained through molecular screening.

[0052] Trait identification: In the T2 generation homozygous edited lines, the expression level of the Bsdr1 gene was upregulated by 2.7 times compared with the wild type; the average disease grade of rice blast decreased from 7.1 to 2.3, the length of sheath blight lesions was shortened by 58%, and the resistance grade of brown planthopper increased from 9 to 3; at the same time, yield traits such as plant height, number of grains per panicle, and thousand-grain weight were not significantly different from those of the wild type, achieving precise and targeted improvement of disease and pest resistance traits.

[0053] Example 4: Implementation of the Molecular Marker-Assisted Breeding Module

[0054] This embodiment uses the marker-assisted backcross breeding process as an example to rapidly cultivate near-isogenic lines. Using RW12 as the donor and the main indica rice variety Yangdao 6 as the recurrent parent, marker-assisted backcross breeding is carried out using the Bsdr1-InDel1 marker:

[0055] Breeding process: F1 is obtained by hybridization and backcrossed for 3 consecutive generations; 200 backcross plants are planted in each generation, and leaf DNA is extracted during the seedling stage. Foreground selection is performed using Bsdr1-InDel1 to screen for heterozygous disease-resistant single plants; at the same time, background selection is performed using 500 whole-genome SNP markers to screen for single plants with the highest background recovery rate to enter the next generation; BC3F1 is self-crossed to obtain BC3F2, and homozygous disease-resistant single plants are screened.

[0056] Results: The homozygous near-isogenic line obtained in the BC3F2 generation showed a background reversion rate of 98.6%, and achieved at least moderate resistance to rice blast, sheath blight, and brown planthopper. Its agronomic traits were not significantly different from Yangdao 6. The entire breeding process took only 2.5 years, nearly 4 years shorter than traditional backcross breeding.

[0057] Example 5: Integrated Breeding Application with Dual-Module Linkage

[0058] First, donor materials carrying both the superior Bsdr1 allele and the rice blast resistance gene Pi9 were created using a functional gene-directed improvement module. Then, the two genes were simultaneously transferred into the main cultivated varieties using a molecular marker-assisted breeding module.

[0059] By using the linkage markers Bsdr1-InDel1 and Pi9, homozygous single plants with both genes were simultaneously screened in the F2 population, and the selection rate conformed to Mendelian inheritance laws.

[0060] Phenotypic identification showed that the dual-gene composite lines exhibited high resistance to rice blast, while also showing resistance to sheath blight and brown planthopper. Their resistance spectrum and persistence were significantly superior to single-gene materials, effectively addressing production scenarios involving multiple diseases and pests. This integrated approach seamlessly connects germplasm innovation with variety improvement, increasing overall breeding efficiency by more than three times compared to traditional techniques.

[0061] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents. In conclusion, if those skilled in the art, inspired by this description, design similar structural methods and embodiments without departing from the inventive spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A dual-application system for molecular design breeding of broad-spectrum disease and insect resistance in cereals, characterized in that, It includes the broad-spectrum disease and insect resistance major functional gene Bsdr1, a codominant molecular marker group closely linked to Bsdr1, as well as a functional gene targeted improvement module and a molecular marker-assisted breeding module; Bsdr1 is a gene encoding a cell membrane localization pattern recognition receptor naturally present in cereal crops. It activates the plant's basic immune pathway by recognizing molecular patterns related to pathogenic fungi and insect feeding, mediating broad-spectrum dominant resistance to a variety of fungal diseases and agricultural pests. The codominant molecular marker group is less than 0.5 cM genetically distant from the Bsdr1 gene, and the marker genotype and the disease-resistant phenotype co-segregate. The functional gene-directed improvement module is used to discover the superior natural variants of Bsdr1 or the function of directed regulatory genes to create broad-spectrum disease and pest resistant germplasm; the molecular marker-assisted breeding module is used to carry out precise genotype selection using the molecular marker set to achieve efficient transfer of disease and pest resistant traits and multi-gene aggregation; the two modules can be implemented independently or in conjunction, covering the entire breeding process from germplasm innovation to variety cultivation.

2. The dual application system according to claim 1, characterized in that, The Bsdr1 gene contributes 35% to 50% to the disease and pest phenotype; its mediated resistance spectrum covers at least three fungal diseases among rice blast, sheath blight, wheat stripe rust, powdery mildew, and maize leaf spot, as well as two pests among rice brown planthopper, rice stem borer, wheat aphid, and corn borer. The Bsdr1 gene activates the MAPK cascade by recognizing chitin in fungal cell walls and effectors in insect oral secretions, upregulating the expression of phytoalexin synthesis genes and insect protease inhibitor genes, and simultaneously inducing callose deposition to build a physical defense barrier, thus achieving synergistic regulation of disease and insect resistance. The Bsdr1 gene contains the superior haplotype Bsdr1-Hap1, whose natural mutations in the promoter region upregulate gene expression by 2-3 times, increasing crop disease and insect resistance by 2-3 levels. Furthermore, this gene has functionally conserved homologs in the collinear regions of rice, wheat, and maize.

3. The dual application system according to claim 1, characterized in that, The codominant molecular marker group includes the conventional gel-detectable Bsdr1-InDel1 marker and the high-throughput fluorescence-detectable Bsdr1-K1 marker. The primers of the molecular marker set are designed in conserved genomic regions flanking the polymorphic sites, and have amplification specificity in rice, wheat, and maize, and can be applied across crops; The molecular marker set can distinguish between three genotypes: homozygous disease resistance, heterozygous, and homozygous disease susceptibility. The phenotypic selection accuracy is ≥98% in segregating populations and phenotypic concordance rate is ≥97% in natural germplasm.

4. The dual application system according to claim 1, characterized in that, The functional gene-directed modification module includes at least one of the following implementation paths: (1) Screening pathway for superior natural allelic variations: Using the Bsdr1 haplotype detection marker, materials carrying the superior haplotype Bsdr1-Hap1 in germplasm resource banks, local varieties or wild closely related species are screened as breeding donors to adapt to non-transgenic breeding systems. (2) Endogenous gene targeted editing pathway: By using gene editing technology to knock out the negative regulatory element of the endogenous Bsdr1 promoter in the recipient crop, or to replace the negative regulatory site in the coding region, gene expression and protein activity can be improved without introducing exogenous genes, thereby improving the resistance of the main cultivated varieties in a targeted manner. (3) Gene overexpression enhancement pathway: construct plant expression vectors carrying the superior allele of Bsdr1-Hap1, obtain gene overexpression lines through genetic transformation, create high-resistance germplasm, and adapt to the breeding needs of areas with high incidence of pests and diseases.

5. The dual application system according to claim 1, characterized in that, The molecular marker-assisted breeding module includes at least one of the following application processes: (1) Marker-assisted backcross breeding process: Using materials carrying the superior Bsdr1 allele as donors and the main cultivated varieties as recurrent parents, target gene foreground selection and whole genome background selection are carried out simultaneously in the backcross generation. Near-isogenic lines with a background recovery rate of ≥95% can be obtained after 2 backcross generations. The breeding cycle is shortened by more than 50% compared with traditional backcross. (2) Multi-gene aggregation breeding process: Combine the Bsdr1 molecular marker with linkage markers of other disease-resistant, insect-resistant, high-yield, and high-quality genes, and simultaneously carry out multi-gene genotyping selection in the segregating generation to aggregate multiple beneficial genes to cultivate durable resistant varieties. (3) Early generation joint selection process: Prospect selection and background screening are carried out simultaneously during the low generation seedling stage of hybridization, eliminating more than 90% of non-target plants in advance, reducing the size of the field identification population, and reducing breeding costs.

6. The dual application system according to claim 1, characterized in that, The implementation method of the two modules working together is as follows: first, the functional gene-directed improvement module creates core donor germplasm carrying the superior Bsdr1 allele and with excellent agronomic traits; then, the molecular marker-assisted breeding module transfers the target gene in batches to the main varieties in different ecological zones, realizing the integrated promotion of germplasm innovation, variety improvement and industrial application, and improving the overall breeding efficiency by more than 3 times.

7. The dual application system according to claim 1, characterized in that, The system can be equipped with an automated nucleic acid extraction platform and a high-throughput genotyping platform to establish a standardized testing process. It can complete genotyping of tens of thousands of samples per day, meeting the large-scale screening needs of commercial breeding.

8. The application of the dual-application system according to any one of claims 1-7 in the innovation of disease and pest resistant germplasm or the breeding of varieties of cereal crops.

9. The application according to claim 8, characterized in that, The cereal crops include any one or more of rice, wheat, corn, barley, and sorghum.

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