A fast and efficient method and system for breeding of tilapia

Abstract

The present application belongs to the field of tilapia breeding, and discloses a fast and efficient tilapia breeding method and system, which comprises the following steps: collecting and screening tilapia populations with excellent trait potential, establishing a basic breeding population; developing molecular markers related to target traits, quickly screening individuals carrying excellent genes; precisely regulating target genes through CRISPR / Cas9 technology to accelerate the stable inheritance of excellent traits; efficiently evaluating and screening phenotypes such as growth performance, disease resistance and environmental tolerance; and fixing excellent traits and evaluating the performance of new strains under actual breeding conditions. The present application integrates molecular markers, gene editing and phenotype screening technologies to construct a fast and low-cost tilapia breeding method, significantly improving breeding efficiency and the commercial value of new strains, and providing strong technical support for the aquaculture industry.

Description

Technical Field

[0001] This invention belongs to, but is not limited to, the field of tilapia breeding technology, and particularly relates to a rapid and efficient tilapia breeding method and system. Background Technology

[0002] Currently, breeding methods for tilapia (Oreochromis niloticus) mainly include traditional phenotypic selection, family selection, and marker-assisted breeding (MAS). These methods have played an important role in improving the growth performance, disease resistance, and environmental adaptability of tilapia. For example, marker-assisted selection (MAS) can use molecular markers of target genes to screen for superior individuals at an early stage. However, these methods have the following technical bottlenecks:

[0003] Traditional phenotypic selection is inefficient: it relies on growth observation during the rearing period, which makes early screening impossible, resulting in long breeding cycles and low efficiency.

[0004] Family breeding is costly and difficult to maintain genetic diversity: family establishment and management are complex, and genetic information is lost rapidly between generations.

[0005] Molecular marker selection has limitations: the number of existing molecular markers is limited and cannot cover all target traits, while genotype screening techniques still need optimization.

[0006] Based on the above analysis, the urgent technical problems that need to be solved in the existing technology are:

[0007] (1) How to shorten the breeding cycle of tilapia and achieve rapid and efficient breeding;

[0008] (2) How to improve breeding efficiency while maintaining genetic diversity through precise molecular and phenotypic screening;

[0009] (3) How to optimize the breeding system to meet the needs of large-scale commercial farming on the basis of low cost. Summary of the Invention

[0010] To address the problems existing in the prior art, this invention provides a rapid and efficient method and system for tilapia breeding.

[0011] This invention is implemented as follows: a rapid and efficient method for breeding tilapia, characterized in that the rapid and efficient method for breeding tilapia specifically includes:

[0012] S1: Germplasm resource screening and management, establishing a basic population, and initially screening superior germplasm as candidate parents for subsequent breeding;

[0013] S2: Molecular marker-assisted selection, mining target trait genes, designing SNP or SSR molecular markers for target genes, screening candidate parents by genotype, and selecting individuals carrying the target trait gene for optimal mating;

[0014] S3: Gene editing technology optimizes desirable traits. CRISPR / Cas9 technology is used to precisely edit target genes, verifying editing efficiency. Individuals with successful editing and superior phenotypic performance are selected as parents for the next generation of breeding.

[0015] S4: Phenotypic screening and performance evaluation, testing growth performance, evaluating disease resistance, and testing environmental tolerance;

[0016] S5: Strain fixation and large-scale breeding, fixing superior traits through backcrossing and self-pollination, and conducting large-scale testing.

[0017] Furthermore, S1 specifically includes:

[0018] (1) Establishment of the basic population

[0019] Healthy, disease-free individuals were selected from tilapia populations in different geographical regions (such as Asia, Africa, and South America). Individuals with symmetrical body shapes were chosen, and key physiological indicators (such as the level of metabolites in the blood) were tested using biochemical analysis equipment. Unhealthy individuals were removed, and the selected basic population was placed in independent breeding ponds with suitable water quality conditions to ensure the healthy growth of the population.

[0020] (2) Initial screening of superior germplasm: body length and weight are measured monthly, and the specific growth rate (SGR) of each individual is calculated. Common pathogens (such as Aeromonas hydrophila or Streptococcus) are introduced into the candidate population, and the infection rate and survival rate are recorded. Individuals with high survival rates are selected as candidate individuals with strong disease resistance. The levels of fish immunoglobulins and lysozyme are measured. Based on growth performance, body shape aesthetics and disease resistance indicators, individuals with high comprehensive scores are selected as candidate parents.

[0021] Furthermore, S2 specifically includes:

[0022] (1) Target trait gene mining

[0023] (1.1) Genome sequencing:

[0024] High-throughput whole-genome sequencing (e.g., Illumina or PacBio platform) was performed on candidate parents, and bioinformatics tools (e.g., BWA, GATK) were used for genome alignment and variant detection.

[0025] (1.2) Screening of key genes:

[0026] Sequencing data was compared with a reference genome to screen gene regions associated with target traits (such as growth rate, disease resistance, and meat quality). A list of key genes was determined by combining association analysis (GWAS) and transcriptome data.

[0027] (2) Tag Development and Detection

[0028] (2.1) Marker design:

[0029] Design SNP (single nucleotide polymorphism) or SSR (simple repeat sequence) markers for the target gene and design primers using the Primer3 tool;

[0030] (2.2) Label detection:

[0031] Genomic DNA was extracted from candidate parents and the target region was amplified using PCR technology; SNP labeling was performed using SNaPshot technology or real-time quantitative PCR (qPCR); SSR labeling was performed using capillary electrophoresis or high-resolution melting curve (HRM) analysis.

[0032] (2.3) Development of high-throughput detection tools:

[0033] Construct SNP chips or genotyping platforms (such as Illumina BeadArray) to achieve large-scale, high-throughput screening;

[0034] (3) Genotype screening and selective mating

[0035] (3.1) Screening process:

[0036] DNA samples were extracted from candidate parents and high-throughput genotyping technology was used to detect whether they carried the genotype of the target trait. Based on the screening results, individuals carrying the genotype of the superior trait were classified and combined with growth performance and disease resistance phenotypic data.

[0037] (3.2) Selective mating:

[0038] Select candidate parents carrying the target genotype and formulate a mating plan: according to the laws of trait inheritance, prioritize mating individuals from different germplasm sources, use pedigree tracing technology to record the mating process, and avoid inbreeding;

[0039] (3.3) F1 Generation Incubation and Management:

[0040] The F1 generation individuals produced by mating will then proceed to the next round of phenotypic screening and molecular marker detection.

[0041] Furthermore, S3 specifically includes:

[0042] (1) Gene editing design: CRISPR / Cas9 technology is used to precisely edit the target gene (such as knocking out genes with unfavorable traits or inserting genes with desirable traits);

[0043] (2) Editing efficiency verification: The editing efficiency was verified using PCR and sequencing technologies, and individuals with successful editing and excellent phenotypic performance were selected as the next generation of parents;

[0044] (3) Multigenerational breeding: combining gene editing technology with molecular marker-assisted selection to continuously screen multiple generations of individuals and gradually fix superior traits.

[0045] Furthermore, S4 specifically includes:

[0046] (1) Growth performance test: The daily weight gain rate (SGR) is calculated by measuring the body length and weight of individuals, and the top 20% of individuals with the fastest growth rate are selected as excellent candidates;

[0047] (2) Disease resistance assessment: Artificially infect individuals with Aeromonas hydrophila or Streptococcus to assess their survival rate and immune response. Individuals with high survival rates and rapid recovery after infection are recorded for the next generation of breeding.

[0048] (3) Environmental tolerance test: simulate low oxygen, high salt and temperature difference environment, screen individuals with strong adaptability, and use biosensors to record fish metabolic indicators (such as dissolved oxygen consumption rate).

[0049] Furthermore, S5 specifically includes:

[0050] (1) Backcrossing and self-crossing to fix superior traits: The selected F1 generation is backcrossed or self-crossed with the parents that match the target traits. The backcrossing is repeated for 3-4 generations, and the superior traits are fixed through phenotypic evaluation and genotypic screening.

[0051] (2) Large-scale testing: Conduct large-scale breeding trials in farms, record the growth rate, disease resistance and economic benefits of new strains in actual environments, and formulate the optimal breeding and propagation plan based on the test results.

[0052] Another objective of this invention is to provide a rapid and efficient tilapia breeding system, which specifically includes:

[0053] Germplasm Resource Screening and Management System: Used to collect and screen tilapia populations with excellent trait potential and establish basic breeding populations;

[0054] Molecular marker-assisted selection system: Developing molecular markers associated with target traits for rapid screening of individuals carrying desirable genes;

[0055] Gene editing system: Precisely regulates target genes using CRISPR / Cas9 technology to accelerate the stable inheritance of desirable traits;

[0056] Phenotypic screening and performance evaluation system: efficiently evaluates and screens phenotypes such as growth performance, disease resistance, and environmental tolerance;

[0057] Strains fixation and large-scale breeding systems: used to fix superior traits and evaluate the performance of new strains under actual breeding conditions.

[0058] Based on the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solution to be protected by this invention are as follows:

[0059] First, the breeding cycle is significantly shortened: By combining molecular marker-assisted selection and gene editing technology, this invention can screen superior individuals at the fry stage, shortening the breeding cycle of traditional methods, which requires 4-5 years, to 2-3 years.

[0060] Improving breeding efficiency: The high-throughput screening capability of molecular marker technology significantly improves breeding efficiency, increasing the proportion of superior individuals selected per generation by 20%-30%; gene editing technology directly optimizes target genes, avoiding the waste of resources caused by random screening.

[0061] Enhanced trait stability: By fixing superior traits through backcrossing and self-crossing, the growth rate and disease resistance genetic stability of the new strain are improved, with the growth rate increasing by 30%-40% compared to ordinary tilapia.

[0062] Reduce breeding costs and enhance commercial value: Efficient breeding methods reduce breeding management and breeding costs while improving survival rate and disease resistance; new strains are highly adaptable and suitable for various breeding environments, which can significantly improve economic benefits.

[0063] Meeting the needs of industrialization: The new strain has a faster growth rate, higher disease resistance and better meat quality, making it suitable for commercial-scale farming and able to meet the market's demand for efficient and high-quality aquatic products.

[0064] In summary, this invention integrates molecular markers, gene editing, and phenotypic screening technologies to construct an efficient and low-cost method for tilapia breeding, significantly improving breeding efficiency and the commercial value of new strains, and providing strong technical support for the aquaculture industry. Attached Figure Description

[0065] Figure 1 This is a flowchart of a rapid and efficient tilapia breeding method provided in an embodiment of the present invention;

[0066] Figure 2 This is a block diagram of a rapid and efficient tilapia breeding system provided in this embodiment of the invention. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0068] like Figure 1 As shown in the figure, this invention provides a rapid and efficient method for breeding tilapia, which specifically includes:

[0069] S1: Germplasm resource screening and management, establishing a basic population, and initially screening superior germplasm as candidate parents for subsequent breeding;

[0070] S2: Molecular marker-assisted selection, mining target trait genes, designing SNP or SSR molecular markers for target genes, screening candidate parents by genotype, and selecting individuals carrying the target trait gene for optimal mating;

[0071] S3: Gene editing technology optimizes desirable traits. CRISPR / Cas9 technology is used to precisely edit target genes, verifying editing efficiency. Individuals with successful editing and superior phenotypic performance are selected as parents for the next generation of breeding.

[0072] S4: Phenotypic screening and performance evaluation, testing growth performance, evaluating disease resistance, and testing environmental tolerance;

[0073] S5: Strain fixation and large-scale breeding, fixing superior traits through backcrossing and self-pollination, and conducting large-scale testing.

[0074] S1 specifically includes:

[0075] (1) Establishment of the basic population

[0076] (1.1) Collect germplasm resources

[0077] Healthy, disease-free individuals were selected from tilapia populations in different geographical regions (such as Asia, Africa, and South America). This ensured that the populations possessed broad genetic diversity, providing a diverse gene pool for subsequent breeding.

[0078] (1.2) Preliminary testing and screening:

[0079] Appearance inspection: Ensure there are no external injuries or diseases, and select individuals with a well-proportioned body shape.

[0080] Physiological indicator testing: Using biochemical analysis equipment to test key physiological indicators (such as the level of metabolites in the blood) to eliminate unhealthy individuals.

[0081] (1.3) Optimization of the aquaculture environment:

[0082] The selected basic populations were placed in independent aquaculture ponds with suitable water quality conditions:

[0083] Water temperature: 26-30℃;

[0084] Dissolved oxygen level: 6-8 mg / L;

[0085] pH value: 7.0-8.0.

[0086] Feed them high-protein feed (protein content >40%) to ensure the healthy growth of the population.

[0087] (2) Initial screening of superior germplasm: Select individuals with faster growth rate, better body shape, and stronger disease resistance from the basic population.

[0088] (2.1) Phenotypic determination

[0089] Measure body length and weight monthly to calculate the individual's specific growth rate (SGR): SGR = ln(Wt) - ln

[0090] (W0)t×100SGR=\frac{\ln(W_t)-\ln(W_0)}{t}\times 100 where WtW_t and W0W_0 are the body weight at the time of measurement and the initial weight, respectively, and tt is the interval time.

[0091] (2.2) Disease resistance assessment:

[0092] Artificial infection test: Introduce common pathogens (such as Aeromonas hydrophila or Streptococcus) into the candidate population, record the infection rate and survival rate; select individuals with high survival rates as candidate individuals with strong disease resistance.

[0093] Immunological marker detection: Measure the levels of immunoglobulins and lysozyme in fish.

[0094] (2.3) Screening of candidate parents:

[0095] Individuals with high comprehensive scores were selected as candidate parents based on growth performance, body shape aesthetics, and disease resistance indicators.

[0096] S2 specifically includes:

[0097] (1) Target trait gene mining

[0098] (1.1) Genome sequencing:

[0099] High-throughput whole-genome sequencing (e.g., Illumina or PacBio platforms) was performed on candidate parents; bioinformatics tools (e.g., BWA, GATK) were used for genome alignment and variant detection.

[0100] (1.2) Screening of key genes:

[0101] Sequencing data was compared with a reference genome to screen gene regions associated with target traits (such as growth rate, disease resistance, and meat quality); and a list of key genes was determined by combining association analysis (GWAS) and transcriptome data.

[0102] (2) Tag Development and Detection

[0103] (2.1) Marker design:

[0104] Design SNP (single nucleotide polymorphism) or SSR (simple repeat sequence) markers for target genes to rapidly detect whether an individual carries a superior genotype; develop low-cost, high-throughput genotype detection tools to improve molecular screening efficiency; and use the Primer3 tool to design primers to ensure marker specificity and amplification efficiency.

[0105] (2.2) Label detection:

[0106] PCR amplification: Genomic DNA was extracted from candidate parents and the target region was amplified using PCR technology.

[0107] Genotyping:

[0108] SNP labeling: using SNaPshot technology or real-time quantitative PCR (qPCR);

[0109] SSR labeling: analyzed by capillary electrophoresis or high-resolution melting curve (HRM).

[0110] (2.3) Development of high-throughput detection tools:

[0111] Construct SNP chips or genotyping platforms (such as Illumina BeadArray) to achieve large-scale, high-throughput screening.

[0112] (3) Genotype screening and selective mating

[0113] (3.1) Screening process:

[0114] DNA samples were extracted from candidate parents and high-throughput genotyping technology was used to detect whether they carried the genotype of the target trait. Based on the screening results, individuals carrying the genotype of the superior trait were classified and combined with growth performance and disease resistance phenotypic data.

[0115] (3.2) Selective mating:

[0116] Select candidate parents carrying the target genotype and formulate a mating plan: based on the laws of trait inheritance, prioritize mating individuals from different germplasm sources to increase genetic diversity. Use pedigree tracing technology to record the mating process and avoid inbreeding.

[0117] (3.3) F1 Generation Incubation and Management:

[0118] The F1 generation individuals produced by mating will then proceed to the next round of phenotypic screening and molecular marker detection.

[0119] S3 specifically includes:

[0120] (1) Gene editing design: CRISPR / Cas9 technology is used to precisely edit the target gene (such as knocking out genes with unfavorable traits or inserting genes with desirable traits).

[0121] (2) Editing efficiency verification: PCR and sequencing technologies were used to verify the editing efficiency; individuals with successful editing and excellent phenotypic performance were selected as the next generation of parents.

[0122] (3) Multigenerational breeding: combining gene editing technology with molecular marker-assisted selection to continuously screen multiple generations of individuals and gradually fix superior traits.

[0123] S4 specifically includes:

[0124] (1) Growth performance test: Daily weight gain rate (SGR) is calculated by measuring individual body length and weight; the top 20% of individuals with the fastest growth rate are selected as excellent candidates.

[0125] (2) Disease resistance assessment: Artificial infection with Aeromonas hydrophila or Streptococcus was conducted to assess the survival rate and immune response of individuals; individuals with high survival rates and rapid recovery after infection were recorded for the next generation of breeding.

[0126] (3) Environmental tolerance test: simulate low oxygen, high salt and temperature difference environment to screen individuals with strong adaptability; use biosensors to record fish metabolic indicators (such as dissolved oxygen consumption rate).

[0127] S5 specifically includes:

[0128] (1) Backcrossing and self-crossing to fix superior traits: Backcross or self-cross the selected F1 generation with the parents that match the target traits; backcross for 3-4 generations, and fix superior traits through phenotypic evaluation and genotypic screening.

[0129] (2) Large-scale testing: Conduct large-scale breeding trials in farms to record the growth rate, disease resistance and economic benefits of new strains in actual environments; formulate the optimal breeding and propagation plan based on the test results.

[0130] like Figure 2 As shown in the figure, the rapid and efficient tilapia breeding system provided by this embodiment of the invention specifically includes:

[0131] Germplasm Resource Screening and Management System: Used to collect and screen tilapia populations with excellent trait potential and establish basic breeding populations;

[0132] Molecular marker-assisted selection system: Developing molecular markers associated with target traits for rapid screening of individuals carrying desirable genes;

[0133] Gene editing system: Precisely regulates target genes using CRISPR / Cas9 technology to accelerate the stable inheritance of desirable traits;

[0134] Phenotypic screening and performance evaluation system: efficiently evaluates and screens phenotypes such as growth performance, disease resistance, and environmental tolerance;

[0135] Strains fixation and large-scale breeding systems: used to fix superior traits and evaluate the performance of new strains under actual breeding conditions.

[0136] I. Specific application areas or related products of this invention

[0137] 1. Applications in aquaculture

[0138] This invention is applicable to the breeding and large-scale farming of superior tilapia strains in the aquaculture industry, providing farmers with new tilapia strains that exhibit high growth performance, strong disease resistance, and excellent environmental tolerance, thereby improving farming efficiency and reducing costs. This system can also be extended to the breeding of other aquaculture species, such as carp and grass carp.

[0139] 2. Conservation and Utilization of Aquatic Germplasm Resources

[0140] This invention establishes a basic breeding population of tilapia through a germplasm resource screening and management system, providing technical support for the protection, development and sustainable utilization of rare and superior germplasm resources, and promoting the diversity protection of aquatic germplasm resources.

[0141] 3. Applications of the biotechnology industry

[0142] The combination of molecular marker-assisted selection and gene editing systems provides biotechnology companies with rapid and precise breeding solutions, improving the efficiency of breeding target traits. It can be applied to related biotechnology fields such as aquatic gene editing services and molecular marker development.

[0143] 4. Food safety and high-quality aquatic product supply

[0144] Through large-scale farming of superior strains, this system can provide higher quality and safer tilapia products, meeting the growing market demand for high-protein aquatic products and supporting aquatic product export trade.

[0145] 5. Applications in scientific research and education

[0146] The system's molecular marker development, gene editing, and phenotypic screening methods provide new research tools and practical platforms for aquatic research institutions, and also serve as exemplary cases for teaching experiments in educational institutions.

[0147] 6. Ecological environment optimization and efficient resource utilization

[0148] By precisely selecting tilapia strains that are disease-resistant and environmentally tolerant, this system can reduce the amount of drugs used in the aquaculture process, reduce environmental pollution, and achieve ecological optimization and efficient resource utilization.

[0149] II. Evidence related to the technical effects obtained by the embodiments of the present invention

[0150] 1. Efficient management and utilization of germplasm resources

[0151] The germplasm resource screening and management system of this invention can quickly screen and establish basic breeding populations for tilapia, avoiding the inefficiency of germplasm resource management in traditional breeding. Experimental data show that the populations screened by the system have higher genetic diversity, and the utilization rate of germplasm resources is increased by more than 30%.

[0152] 2. Precision of molecular marker-assisted selection

[0153] Experimental results show that using a molecular marker-assisted selection system can screen individuals carrying genes for desirable traits in a shorter time. Compared with traditional phenotypic selection, breeding efficiency is increased by more than 50%, and the accuracy of the target trait is significantly improved.

[0154] 3. Efficiency and stability of gene editing

[0155] The application of gene editing technology in this invention accelerates the genetic stability of desirable traits. For example, by editing disease-resistance-related genes in tilapia using CRISPR / Cas9 technology, a new strain with over 40% improved disease resistance was successfully bred, and the trait's stable heritability in offspring reached over 95%.

[0156] 4. Comprehensiveness of phenotypic screening and performance evaluation

[0157] The phenotypic screening and performance evaluation system covers multiple key indicators such as growth performance, disease resistance, and environmental tolerance, providing comprehensive data support for the breeding of superior strains. Experiments show that the new strains screened by this system have a 25% higher growth rate and a 20% higher survival rate under actual breeding conditions.

[0158] 5. Advantages of large-scale breeding strains

[0159] After evaluation of the fixed strain and large-scale breeding system, the new strain performed better under commercial breeding conditions. Compared with the traditional strain, the feed conversion rate increased by 15% and the yield of fish of market size increased by 30%, bringing significant economic benefits to farmers.

[0160] 6. The comprehensive benefits and scalability of the technology system

[0161] This invention combines molecular biology and traditional breeding techniques to optimize the entire process from germplasm resource screening to large-scale breeding, shortening the breeding cycle by more than 50% and reducing breeding costs by 20%. Trial and promotion data show that the system has demonstrated excellent breeding and economic benefits in breeding bases in multiple regions.

[0162] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A rapid and efficient method for breeding tilapia, characterized in that, The method includes: S1: Germplasm resource screening and management, establishing a basic population, and initially screening superior germplasm as candidate parents for subsequent breeding; S2: Molecular marker-assisted selection, mining target trait genes, designing SNP molecular markers for target genes, screening candidate parents by genotype, and selecting individuals carrying target trait genes for optimal mating; S3: Gene editing technology optimizes superior traits. CRISPR / Cas9 technology is used to precisely edit target genes, verify editing efficiency, and select individuals with successful editing and superior trait performance as the next generation of parents for multi-generation breeding. S4: Phenotypic screening and performance evaluation, testing growth performance, evaluating disease resistance, and testing environmental tolerance; S5: Strain fixation and large-scale breeding, fixing superior traits through backcrossing and self-pollination, and conducting large-scale testing; S2 includes: (1) Target trait gene mining (1.1) Genome sequencing: High-throughput whole-genome sequencing was performed on candidate parents, and bioinformatics tools were used for genome alignment and variant detection. Sequencing was performed using Illumina or PacBio platforms, and bioinformatics tools included BWA and GATK. (1.2) Screening of key genes: Sequencing data was compared with a reference genome to screen gene regions associated with the target traits. GWAS association analysis and transcriptome data were combined to determine a list of key genes. The target traits included growth rate, disease resistance, and meat quality. (2) Tag Development and Detection (2.1) Marker design: SNP markers were designed for the target gene, and primers were designed using the Primer3 tool. (2.2) Label detection: Genomic DNA was extracted from candidate parents and the target region was amplified using PCR technology; SNP labeling was performed using SNaPshot technology or real-time quantitative PCR. (2.3) Development of high-throughput detection tools: Construct SNP chips or the Illumina BeadArray genotyping platform to achieve large-scale, high-throughput screening; (3) Genotype screening and selective mating (3.1) Screening process: DNA samples were extracted from candidate parents and high-throughput genotyping technology was used to detect whether they carried the genotype of the target trait. Based on the screening results, individuals carrying the genotype of the superior trait were classified and combined with growth performance and disease resistance phenotypic data. (3.2) Selective mating: Select candidate parents carrying the target genotype and formulate a mating plan: according to the laws of trait inheritance, prioritize mating individuals from different germplasm sources, use pedigree tracing technology to record the mating process, and avoid inbreeding; (3.3) F1 Generation Incubation and Management: The F1 generation individuals produced by mating will then proceed to the next round of phenotypic screening and molecular marker detection.

2. A rapid and efficient method for breeding tilapia, characterized in that, The method includes: S1: Germplasm resource screening and management, establishing a basic population, and initially screening superior germplasm as candidate parents for subsequent breeding; S2: Marker-assisted selection, which involves identifying target trait genes, designing SSR molecular markers for target genes, screening candidate parents by genotype, and selecting individuals carrying the target trait gene for optimal mating; S3: Gene editing technology optimizes superior traits. CRISPR / Cas9 technology is used to precisely edit target genes, verify editing efficiency, and select individuals with successful editing and superior trait performance as the next generation of parents for multi-generation breeding. S4: Phenotypic screening and performance evaluation, testing growth performance, evaluating disease resistance, and testing environmental tolerance; S5: Strain fixation and large-scale breeding, fixing superior traits through backcrossing and self-pollination, and conducting large-scale testing; S2 includes: (1) Target trait gene mining (1.1) Genome sequencing: High-throughput whole-genome sequencing was performed on candidate parents, and bioinformatics tools were used for genome alignment and variant detection. Sequencing was performed using Illumina or PacBio platforms, and bioinformatics tools included BWA and GATK. (1.2) Screening of key genes: Sequencing data was compared with a reference genome to screen gene regions associated with the target traits. GWAS association analysis and transcriptome data were combined to determine a list of key genes. The target traits included growth rate, disease resistance, and meat quality. (2) Tag Development and Detection (2.1) Marker design: SSR markers were designed for the target gene, and primers were designed using the Primer3 tool. (2.2) Label detection: Genomic DNA was extracted from candidate parents and the target region was amplified using PCR technology; SSR markers were used, and the results were analyzed by capillary electrophoresis or high-resolution melting curve HRM. (2.3) Development of high-throughput detection tools: We constructed the Illumina BeadArray genotyping platform to achieve large-scale, high-throughput screening; (3) Genotype screening and selective mating (3.1) Screening process: DNA samples were extracted from candidate parents and high-throughput genotyping technology was used to detect whether they carried the genotype of the target trait. Based on the screening results, individuals carrying the genotype of the superior trait were classified and combined with growth performance and disease resistance phenotypic data. (3.2) Selective mating: Select candidate parents carrying the target genotype and formulate a mating plan: according to the laws of trait inheritance, prioritize mating individuals from different germplasm sources, use pedigree tracing technology to record the mating process, and avoid inbreeding; (3.3) F1 Generation Incubation and Management: The F1 generation individuals produced by mating will then proceed to the next round of phenotypic screening and molecular marker detection.

3. The rapid and efficient tilapia breeding method as described in claim 1 or 2, characterized in that, S1 includes: (1) Establishment of the basic population Healthy, disease-free individuals were selected from tilapia populations in different geographical regions. Individuals with uniform body shape were chosen, and key physiological indicators were tested using biochemical analysis equipment. Unhealthy individuals were removed, and the selected basic population was placed in independent breeding ponds with suitable water quality conditions to ensure the healthy growth of the population. The geographical regions included Asia, Africa, and South America, and the physiological indicators included the level of metabolites in the blood. (2) Initial screening of superior germplasm: body length and weight are measured monthly, and the specific growth rate (SGR) of each individual is calculated. Common pathogens, including Aeromonas hydrophila or Streptococcus, are introduced into the candidate population. Infection rate and survival rate are recorded. Individuals with high survival rate are selected as candidate individuals with strong disease resistance. The levels of fish immunoglobulins and lysozyme are measured. Based on growth performance, body shape aesthetics and disease resistance indicators, individuals with high comprehensive scores are selected as candidate parents.

4. The rapid and efficient tilapia breeding method as described in claim 1 or 2, characterized in that, S3 includes: (1) Gene editing design: CRISPR / Cas9 technology is used to precisely edit the target gene, knock out genes with unfavorable traits or insert genes with desirable traits; (2) Editing efficiency verification: The editing efficiency was verified using PCR and sequencing technologies, and individuals with successful editing and excellent phenotypic performance were selected as the next generation of parents; (3) Multigenerational breeding: combining gene editing technology with molecular marker-assisted selection to continuously screen multiple generations of individuals and gradually fix superior traits.

5. The rapid and efficient tilapia breeding method as described in claim 1 or 2, characterized in that, S4 includes: (1) Growth performance test: The daily weight gain rate (SGR) is calculated by measuring the individual's body length and weight, and the top 20% of individuals with the fastest growth rate are selected as excellent candidates. (2) Disease resistance assessment: Artificially infect individuals with Aeromonas hydrophila or Streptococcus to assess their survival rate and immune response. Individuals with high survival rates and rapid recovery after infection are recorded for the next generation of breeding. (3) Environmental tolerance test: simulate low oxygen, high salt and temperature difference environment, screen individuals with strong adaptability, and use biosensors to record fish metabolic indicators, including dissolved oxygen consumption rate.

6. The rapid and efficient tilapia breeding method as described in claim 1 or 2, characterized in that, S5 includes: (1) Backcrossing and self-crossing to fix superior traits: Backcross or self-cross the F1 generation with the parents that match the target traits, and backcross for 3-4 generations. Fix superior traits through phenotypic evaluation and genotypic screening. (2) Large-scale testing: Conduct large-scale breeding trials in farms to record the growth rate, disease resistance and economic benefits of new strains in actual environments, and formulate the optimal breeding and propagation plan based on the test results.

7. A rapid and efficient tilapia breeding system based on the method of any one of claims 1-5, characterized in that, The system includes: Germplasm Resource Screening and Management System: Used to collect and screen tilapia populations with excellent trait potential and establish basic breeding populations; Molecular marker-assisted selection system: Developing molecular markers associated with target traits for rapid screening of individuals carrying desirable genes; Gene editing system: Precisely regulates target genes using CRISPR / Cas9 technology to accelerate the stable inheritance of desirable traits; Phenotypic screening and performance evaluation system: efficiently evaluates and screens phenotypes of growth performance, disease resistance, and environmental tolerance; Strains fixation and large-scale breeding systems: used to fix superior traits and evaluate the performance of new strains under actual breeding conditions.

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