42 results about "Heredity" patented technology

The invention provides a strain for producing L-2-aminobutyric acid as well as a construction method and application of the strain. According to the strain, E.coli W3110 is taken as a chassis strain, tdh, rhtA and ilvE genes are knocked out, the transcriptional levels of ppc, aspC, thrAfbrBC, ilvAfbr, tdcB, yaS and pntAB genes are up-regulated, an ilvI gene is weakened, bcd and gdh genes derived from bacillus subtilis B.subtilis 168 and a cysK gene derived from Corynebacterium glutamicum K051 are introduced in a heterologous manner, and the L-2-aminobutyric acid producing strain is obtained through screening and screening. The strain does not contain plasmids, is stable in heredity, does not need induction, does not need to add resistant substances, efficiently synthesizes L-2-aminobutyric acid from the beginning by taking glucose as a substrate, and has good L-2-aminobutyric acid synthesis capability, stable performance and high acid production efficiency.

The application provides a multi-source Parkinson's disease database integration method based on LEDD-UPDRS composite index alignment, and is applied to the technical field of data processing. In view of the heterogeneous problems of multi-source Parkinson's disease databases, the application integrates heterogeneous data of PPMI, PDBP and local queues, disassembles characteristics according to four modes of heredity and clinic, introduces a standardized term library and a BERT-BiLSTM-CRF model unified term adjusted in combination with medical corpus, generates a cross-library feature table; a storage architecture is constructed based on FlashROM mode to realize data storage and retrieval; a composite observation system is built with LEDD and UPDRS-III, consistency is verified by multiple methods, data is standardized, missing data is filled in combination with multiple models to generate an integrated data set; a double prediction model is built relying on the data set, and the advantages of the data are realized by a Cohen's d value verification method; finally, cross-library joint analysis is carried out, phenotype-genotype correlation modeling and causal inference are completed, and data support is provided for Parkinson's disease research and clinical prediction.

The invention discloses a rapid breeding method for trichosanthes kirilowii maxim seedling detoxification, belongs to the technical field of trichosanthes kirilowii maxim seedling breeding, aims at solving the problems that traditional breeding is prone to carrying viruses and low in efficiency, and provides high-quality trichosanthes kirilowii maxim seedlings which are low in virus load, do not affect yield and quality and are stable in heredity. The method comprises the following steps: selecting an annual trichosanthes kirilowii maternal plant, screening a healthy maternal plant by using a trichosanthes kirilowii maternal plant healthy screening model, and taking a tender stem section for pretreatment; sterilizing the pretreated tender stem segments, stripping stem tips, and inoculating a starting culture medium to obtain sterile buds; cutting the sterile buds, transferring to a proliferation culture medium, and propagating to obtain bud clusters; screening qualified buds through a trichosanthes kirilowii maxim sterile bud screening model after molecular virus detection on the bud clumps; after qualified buds are subjected to rooting culture, acclimatization seedlings are transplanted into a sterilization matrix, and virus-free trichosanthes kirilowii maxim seedlings are obtained through cultivation in a greenhouse. According to the method, the detoxification effect is controllable, the breeding efficiency is high, the seedling quality is stable, and the obtained detoxified trichosanthes kirilowii maxim seedlings meet the agricultural production requirements, have stable production applicability and are suitable for large-scale production of the trichosanthes kirilowii maxim seedlings.

The application belongs to the field of plant genetic engineering, and particularly relates to application of a rice-derived OsDREB1 gene in enhancing the low-phosphorus stress tolerance of soybeans. A recombinant expression vector of the OsDREB1 gene is constructed, and the soybean plants are transformed by using an agrobacterium-mediated method to obtain a transgenic soybean line with stable heredity. It is found through experiments that overexpression of the OsDREB1 gene in soybeans can enhance the low-phosphorus tolerance of the soybeans, and under the same conditions, the number of pods per plant and the weight of 100 seeds of the transgenic plants are higher than those of a wild control group. The growth performance of soybeans in low-phosphorus soil is improved by using genetic engineering technology, and a new strategy for reducing the dependence of agriculture on phosphorus fertilizer is provided.

The invention discloses an influenza reporter virus carrying a fluorescent RNA aptamer and a construction method and application thereof, and the influenza reporter virus carrying the fluorescent RNA aptamer is obtained by introducing a termination codon TAA into the 328th nucleotide of an ORF region of an NS1 gene on the basis of a genome of an influenza A virus and terminating in advance, then introducing a terminating codon TAA into the 328th nucleotide of the ORF region of the NS1 gene of the influenza A virus; original nucleotides at the 328-480 sites are replaced by forward or reverse RNA aptamers, and the RNA aptamer is obtained. The influenza reporter virus carrying the fluorescent RNA aptamer constructed by the invention also has the characteristics of good virus replication ability, high RNA imaging sensitivity and good specificity on the basis of stable inheritance, can be used for real-time visual observation of virus RNA, and is used for research on virus replication cycle and molecular mechanism related to the virus RNA. Besides, the construction method of the influenza reporter virus carrying the fluorescent RNA aptamer can also be applied to construction of RNA fluorescent reporter viruses of other subtype influenza viruses such as H3N2 and H5N1, and an important tool is provided for real-time tracing of corresponding virus RNA.

The invention relates to the technical field of alfalfa screening, discloses a high-quality and high-yield alfalfa hybrid combination screening method fusing multiple technologies, provides a multi-dimensional coding and double-elite evolution mechanism, constructs an improved non-dominated sorting genetic algorithm-II, and provides a high-quality and high-yield alfalfa hybrid combination screening method by coding a hybrid combination into a continuous real number vector. A chromosome expression mode decoupled from a problem structure is constructed, a double-elite mechanism of elite retention and offset mating is introduced, the retention and heredity ability of a high-quality solution is improved, offset crossover and jitter operation is used, premature convergence is avoided, efficient global search of a strain combination space is achieved, and a high-quality solution is obtained. Meanwhile, a multi-omics association model of genes, metabolites and phenotypes is provided, transcriptome, metabolome and molecular marker data are comprehensively utilized, a multi-dimensional character prediction model is constructed, early-stage accurate screening of filial generations is achieved through correlation analysis and marker verification, the error selection rate is reduced, and the breeding period is shortened.

The invention discloses a method for breeding a new variety of Mimai No.18 by using corn and wheat distant hybridization, and relates to the technical field of crop genetic breeding, the method comprises the following steps: parent selection: selecting Mimai No.2 wheat as a female parent and functional 2009-1 black corn as a male parent; emasculation: performing emasculation treatment on the female parent ear, removing anther in each floret, then immediately sleeving the floret with a paper bag, and marking the name of the female parent variety and the emasculation date. A feasible method is provided for wheat breeding by carrying out distant hybridization on wheat and corn and combining an accurately controlled generation-adding propagation technology. According to the method, accurate and quantitative environment management guarantees normal completion of each growth stage, measures such as illumination supplement and chemical control cultivation are taken, and stable expression and selection of excellent characters are promoted. Finally, new materials with consistent characters and stable heredity are successfully bred, and a new technical approach is provided for genetic improvement of wheat.

The application relates to the technical field of genetic engineering, and discloses application of a transcription factor TabHLH168 protein in wheat disease resistance. The amino acid sequence of the TabHLH168 protein is shown as SEQ ID NO. 1; the coding gene sequence of the TabHLH168 protein is shown as SEQ ID NO. 2. The TabHLH168 protein is a target protein of a false smut fungus effect protein FpE02. The application uses the above-mentioned application of the transcription factor TabHLH168 protein in wheat disease resistance, overexpresses the coding gene of the TabHLH168 protein, obtains transgenic wheat with stable heredity and wheat stem base rot resistance, provides a new solution for carrying out wheat disease resistance breeding work, and has important significance in the field of wheat breeding with disease resistance.

The invention discloses a method for cultivating colored snakeheads. Common white snakehead and golden snakehead in Sichuan and Chongqing regions are used as original parents, reciprocal cross, self-group mating and backcross are sequentially completed to establish a paternal line and a maternal line, then matching hybridization is performed to obtain a G0 generation, then white ground color and colored plaques are used as phenotype markers, and 6-8 generations are continuously bred in combination with growth, low temperature resistance and disease resistance. And finally, obtaining the novel colorful snakehead fish strain with various body colors and stable heredity. Compared with white snakehead, the weight of the novel colorful snakehead strain at the age of 180 days is increased by 20% or above, the low-temperature survival rate is increased by 24% or above, the disease resistance is remarkably enhanced, and the novel colorful snakehead strain is suitable for large-scale culture and ornamental fish markets.

The present application relates to the technical field of corn whole genome selection breeding, and discloses a data fusion analysis method and system for corn whole genome selection breeding, which comprises the following steps: collecting multi-dimensional data and constructing a multi-source data fusion network; generating a dynamic breeding data set through noise filtering and format unification processing; obtaining characteristic correlation data through spatiotemporal correlation processing; establishing a data-heredity response relationship model and generating heredity correlation dynamic data; generating core selection range data through selection efficiency correlation processing; constructing a statistical prediction model and optimizing breeding parameters. The system comprises data acquisition, data processing, correlation modeling, efficiency evaluation and selection analysis modules. The present application realizes efficient integration and dynamic analysis of multi-source data, improves the accuracy and efficiency of breeding selection, and is suitable for corn breeding optimization under complex environment.

The application provides a method for breeding a pure white color Wuzhishan pig. The method adopts a strategy of phenotype breeding as the main part and molecular marker monitoring as the auxiliary part, simultaneously uses KIT gene detection to confirm the genotype background of each generation, uses SSR genetic diversity monitoring to guide scientific mating and external blood introduction, avoids inbreeding recession, and through breeding, a new strain of Wuzhishan pig with pure white color, stable heredity and rich blood is obtained.

The present application relates to the technical field of database construction, and particularly relates to a method and system for constructing a reproductive medicine database. The method comprises the following steps: obtaining a patient biological tissue sample; obtaining reproductive endocrine hormone data, embryo morphology parameter data, immune cell function data and genomic variation data of the patient biological tissue sample; performing time series analysis and processing on hormone fluctuation patterns according to the reproductive endocrine hormone data to obtain endocrine dynamic characteristic data; performing image recognition processing based on light coherence superposition characteristics on the embryo morphology parameter data, and performing embryo development potential evaluation to obtain embryo development potential data; and performing hierarchical clustering processing on patient individual heterogeneity according to the immune cell function data and the genomic variation data to obtain patient immune-heredity typing data. The present application realizes standardization of data acquisition through quantum dot sensing technology and a multi-channel microfluidic chip, and solves the problem of heterogeneity of data sources.

The application discloses a method for creating a DH line of eggplant by using anther culture and application thereof, and relates to the technical field of plant breeding. The application establishes a morphological index of a flower bud based on a calyx lobe separation state, replaces a time-consuming microscope examination procedure, and optimizes a combination of heat treatment and low-temperature pretreatment, so that the embryoid induction rate is significantly improved. Finally, through strict ploidy identification and self-pollination purification, a DH line with consistent traits and stable heredity can be obtained, an efficient pure line source is provided for eggplant hybrid breeding, and efficient conversion from a heterozygous genotype plant to a homozygous DH line is realized.

The invention discloses a method for constructing and maintaining a nilaparvata lugens harmful experimental population, and belongs to the technical field of agricultural biology. According to the method, a directional feeding system based on host selection pressure is established, corresponding obligate identification varieties are selected as hosts according to different pest-causing types, and the specific pest-causing characteristics of the hosts are maintained by utilizing the host selection pressure; meanwhile, a regular monitoring system is established, and harmful drift of the population is found and corrected in time through a quality monitoring mechanism that purity spot check is performed every 5 generations and comprehensive evaluation is performed every 20 generations. Through the steps, the standard experimental population with clear damage type and stable heredity of the brown planthopper is constructed and maintained, the problems of inaccurate damage type identification and difficult population purity maintenance in the prior art are solved, and the method is suitable for screening of insect-resistant rice varieties, damage type monitoring and related basic research.

The invention discloses an identification method of a sequence participating in potato centromere relocation, and belongs to the technical field of plant heredity and molecular biology. According to the method, T2T-level genome data and CENH3 ChIP-seq data of different haplotypes of potatoes are integrated, sequence screening, annotation and function prediction are carried out by utilizing a bioinformatics analysis tool, and a satellite DNA sequence which is 2-3Kbp in length, is highly conserved in the same haplotype and can be specifically combined with CENH3 protein is identified. The sequence can induce CENH3 to deposit in a non-native centromere area, so that functional relocation of centromere is realized, and a core molecular element and a technical support are provided for artificial centromere construction, plant chromosome engineering and accurate genome operation. The method solves the problems that in the prior art, a functional sequence for clearly inducing centromere relocation is lacked, a CENH3 targeted recruitment mechanism model is not established and the like, and has a wide application prospect.

The invention provides a skin organoid HPV infection model based on a human embryonic stem cell source and a construction method and application thereof, and relates to the technical field of molecular biology, the construction method comprises the following steps: integrating an HPV genome to an AAVS1 site of genome DNA of a human embryonic stem cell to obtain the human embryonic stem cell carrying the HPV genome, and performing induced differentiation and activation of the HPV genome to obtain the human embryonic stem cell carrying the HPV genome. A skin-like organ HPV infection model is formed, stable heredity and controllable expression of an HPV genome are achieved, virus particle assembly is achieved through induced differentiation, establishment of a virus replication environment, activation of HPV early gene expression, driving of HPV genome replication and induction of late gene expression, and the natural infection state of HPV is simulated. The technical problem that in the prior art, an infection model cannot simulate the life cycle of HPV dependent terminal differentiation is solved, and an irreplaceable technical platform is provided for research of an HPV pathogenic mechanism and research and development of antiviral drugs and vaccines.

The invention discloses an intelligent management system based on sugarcane hybridization data, relates to the technical field of agricultural information, and realizes quantification and prospective judgment of the flowering phase of sugarcane hybridization parents by converting breeding experience from qualitative description to dynamic prediction based on a genetic and environmental interaction relationship. A florescence prediction module calls florescence genotypes of parents from a germplasm resource library and analyzes gene loci related to photoperiod sensitivity of the parents, and meanwhile, a data acquisition module continuously captures real-time environment data of a field and combines the real-time environment data with information such as parent historical florescence, hybrid combinations and hybrid F1 populations; by analyzing the nonlinear relation between the cumulative growth day and the optical periodic function, the inherent physiological process of conversion from vegetative growth to reproductive growth of sugarcane is simulated, the predicted full-bloom stage is accurately calculated, the hysteresis and uncertainty of traditional manual observation and empirical estimation are fundamentally overcome, and the method is suitable for large-scale popularization and application. And a data-driven decision basis is provided for subsequent accurate regulation and control.

The application discloses a reproductive sample information tracking method and system combined with biological feature recognition. The method quantifies the influence of target genes on experimental conditions caused by heredity through an influence coefficient, and to some extent, investigates the correlation between the internal cause of "heredity" and the external cause of "experimental conditions". Although this correlation has no necessary connection with inbreeding degeneration, it is also included in the investigation range considering its negative impact on the experiment. Further, the immune-related gene is one of important factors for ensuring the stability and reliability of experimental data. The application quantifies the influence through an influence degree value, which can effectively quantify the harm and is conducive to realizing the quantization requirement in the reproductive sample information tracking process. It can be seen that the method and system of the application can realize the application of data processing technology for supervision or prediction purposes in the technical field of reproductive sample information tracking.

The invention relates to the technical field of corn whole genome selective breeding, and discloses a data fusion analysis method and system for corn whole genome selective breeding, and the method comprises the steps: collecting multi-dimensional data, and constructing a multi-source data fusion network; performing noise filtering and format unified processing to generate a dynamic breeding data set; performing space-time correlation processing to obtain feature correlation data; establishing a data-genetic response relationship model and generating genetic association dynamic data; selecting efficiency association processing to generate core selection range data; and constructing a statistical prediction model and optimizing breeding parameters. The system comprises a data acquisition module, a data processing module, an association modeling module, an efficiency evaluation module and a selection analysis module. According to the method, efficient integration and dynamic analysis of multi-source data are realized, the accuracy and efficiency of breeding selection are improved, and the method is suitable for corn breeding optimization in a complex environment.

The invention discloses a chrysanthemum salt tolerance high-throughput identification method which comprises the following steps: selecting a plurality of chrysanthemum germplasm resources, setting sodium chloride solutions with different concentrations to carry out salt stress treatment, and carrying out dimensionality reduction calculation on a plurality of salt tolerance related characters through a principal component analysis method to obtain a comprehensive salt tolerance D value; after the salt stress phenotype appears, RGB images of each plant at four side view angles and one overlook angle are collected, and image color calibration and standardized naming are carried out; segmenting the image in an excessive green and HSV color space to obtain a plant binary image, extracting morphological and textural digital characteristic parameters, and analyzing the reliability of the characteristic parameters by using a linear regression model; adopting independent sample t test, variability analysis, feature importance analysis and generalized heritability analysis to screen representative features which are significant in salt stress response and stable in heredity from the digital feature parameters; the screened representative features are divided into a plurality of feature subsets, and a random forest algorithm is adopted to train a salt tolerance prediction model with the representative features as independent variables and salt tolerance D values as dependent variables; on the basis of a salt tolerance prediction model, evaluating the importance of each feature, screening out an optimal feature combination with the minimum prediction error, and performing salt tolerance grade automatic division on the chrysanthemum germplasm resources; according to the invention, lossless dynamic measurement of plants can be realized.

The invention belongs to the field of microorganisms, and particularly relates to monascus purpureus with high yield of essential amino acids as well as a screening method and application thereof. The invention provides a novel trans-membrane differentiation ARTP mutagenesis method aiming at filamentous fungi, aiming at the characteristics of multiple cores and thick walls of monascus, protoplast pretreatment and repair liquid components before mutagenesis are optimized, so that the fatality rate and the positive mutation rate are optimally balanced, and the problem of high instability of monascus heredity caused by conventional ARTP is solved. Based on the novel mutagenesis method, the mutant strain AZA5 is obtained through successful mutagenesis screening. The essential amino acid content of AZA5 is as high as 58%. The invention not only provides an excellent strain resource for industrial production of high-quality microbial protein, but also has important scientific value and wide industrial application potential.

The invention belongs to the technical field of plant biotechnology and molecular breeding, and relates to a ginseng 40K SNP liquid phase breeding chip and application thereof, the chip comprises 41684 SNP sites which are positioned on 24 chromosomes of a ginseng T2T reference genome (v2024), and the ginseng 40K SNP liquid phase breeding chip has the advantages of uniform site distribution, good representativeness, strong specificity and high polymorphism. The application range of the chip covers genetic diversity analysis of ginseng germplasm resources, population structure analysis, heredity and evolution analysis, genetic relationship identification, whole genome association analysis, genome selection and other molecular breeding related researches, the chip is developed based on a high-throughput sequencing technology, the detection throughput is high, detection of nearly thousands of materials can be covered at the same time, and the application range is wide. The method provided by the invention is suitable for mainstream second-generation sequencing platforms such as Illu mina and MGI, is simple, convenient and rapid to operate, provides key technical support for genetic resource innovation, excellent gene mining and precise molecular breeding of the ginseng, assists in cultivation of high-quality, high-yield and stress-resistant new varieties of the ginseng, and improves the core competitiveness of the ginseng industry.

The invention belongs to the technical field of plant heredity and genetic engineering, and particularly relates to soybean RING type E3 ubiquitin ligase GmSSE1 and application thereof. According to the invention, the soybean RING type E3 ubiquitin ligase gene GmSSE1 is separated from soybean Williams 82 (Williams 82), and tests prove that the expression of the gene is induced by salt stress, and the salt tolerance of soybean can be negatively regulated. Besides, according to haplotype analysis and phenotype correlation research, the single plant grain weights of different haplotypes (GmSSE1Hap1, GmSSE1Hap2 and GmSSE1Hap3) of the GmSSE1 in a natural population are obviously different. The invention not only provides an important gene resource for clarification of a plant salt-tolerant molecular mechanism, but also provides an effective molecular target and technical support for crop salt-tolerant genetic improvement, and has important theoretical significance and application potential.

The invention discloses sgRNA for accurately editing a PSEN1 p.M146V site of a tree shrew and application of the sgRNA, and belongs to the technical field of gene editing. The nucleotide sequence of the sgRNA designed by the invention is shown as SEQ ID NO.1. The sgRNA can guide a base editor to be precisely positioned to a PSEN1 p.M146V site, a spermatogonial stem cell line for precisely editing the PSEN1 p.M146V site of the tree shrew is obtained, the precisely edited spermatogonial stem cell line is obtained through single cell cloning, screening and enrichment, and the stably inherited PSEN1 p.M146V gene is obtained through reproductive line transmission to edit the tree shrew. The sgRNA provided by the invention is accurate in design and high in editing efficiency, and the editing efficiency of the obtained tree shrew spermatogonial stem cells is as high as 100%. The spermatogonial stem cell line for precisely editing the tree shrew PSEN1 p.M146V site and the stably inherited PSEN1 p.M146V gene editing tree shrew are obtained for the first time, a research basis is provided for researching the degenerative phenotype, pathological characteristics and molecular mechanism of the Alzheimer's disease caused by the mutation, and an important experimental platform is provided for screening related drugs.

The invention is applicable to the technical field of molecular biology and biology, and provides application of a corn biological clock gene Zmtoc1b in improvement of plant drought tolerance, the nucleotide sequence of the corn biological clock gene Zmtoc1b is shown as SEQ ID NO: 1, and the amino acid sequence of a protein Zmtoc1b encoded by the corn biological clock gene Zmtoc1b is shown as SEQ ID NO: 2. The Zmtoc1b gene is cloned from a corn inbred line B73, Arabidopsis thaliana is transformed through an agrobacterium-mediated method, a T3-generation transgenic line with stable inheritance is obtained, drought stress treatment results show that the drought tolerance of the transgenic Arabidopsis thaliana in the seedling stage is obviously higher than that of a wild type, the relative water content and SOD activity of leaves are increased, and the yield of the transgenic Arabidopsis thaliana is increased. Therefore, it is proved that the corn biological clock gene Zmtoc1b can effectively improve the drought tolerance of plants, and a key gene and technical support are provided for improving the stress resistance of the plants.

The invention discloses application of a GmPHD6 protein and a related biological material thereof in regulating and controlling the oil content of plant seeds. According to the invention, a GmPHD6 gene is over-expressed in a soybean receptor Jack by using a transgenic technology, and a GmPHD6 over-expression strain with stable inheritance is identified and screened out. The detection on the oil content in the GmPHD6 overexpression strain and the soybean receptor Jack seeds shows that compared with the soybean receptor Jack, the oil content of the GmPHD6 overexpression strain seeds is obviously improved and reaches a remarkable level. It is found for the first time that the GmPHD6 protein can positively regulate the grease content of the soybean seeds, the grease content of the soybean seeds can be remarkably improved by improving the GmPHD6 gene expression quantity, and the GmPHD6 protein has important theoretical and practical significance in improving the grease content of crop seeds, especially improving the grease content of the soybean seeds and cultivating high-grease soybean varieties.

The invention relates to a method for cultivating a saline-alkaline tolerant asparagus material by combining compound mutagenesis with high-salt screening, and belongs to the technical field of saline-alkaline tolerant crop cultivation, and the alternate circulating compound mutagenesis treatment method comprises the following steps: carrying out alternate circulating compound mutagenesis treatment on the asparagus material by adopting pingyangmycin and ethyl methanesulfonate; the multi-generation dynamic high-salt screening method comprises the following steps: carrying out multi-generation dynamic high-salt screening on the asparagus materials subjected to alternate cyclic compound mutagenesis treatment; the recovery culture method comprises the step of carrying out recovery culture on the screened asparagus materials. The asparagus with genetic stability and strong salt tolerance is directionally and quickly bred by combining efficient compound mutation with multi-generation dynamic stress screening for simulating a real environment; stress is applied in the seedling stage, extremely sensitive individuals can be rapidly eliminated, the culture cost and space are saved, it is ensured that only the individuals with the strongest salt tolerance can survive and breed, and salt-tolerant genes are enriched generation by generation.

The invention belongs to the technical field of animal models, and discloses a construction method and application of a neutrophil development defect model. The construction method of the neutrophil development defect model comprises the following steps: performing targeted editing on a tead1a gene of zebra fish through CRISPR / Cas9; the nucleotide sequence of the gRNA for editing the tead1a gene is as shown in SEQ ID NO: 1. The tead1a gene is edited in a targeted mode through CRISPR / Cas9 by adopting specific gRNA, the zebra fish neutrophil development defect model which can be stably inherited, is definite in phenotype and long in lifetime is constructed, and the zebra fish neutrophil development defect model can be applied to disease mechanism research and drug screening.

The invention provides a QX-type avian infectious bronchitis virus recombinant attenuated strain as well as a preparation method and application thereof, belongs to the technical field of veterinary biological products, and can solve the problems of long period and poor adaptability in acquisition of attenuated strains through multiple passage of chick embryos. According to the QX type avian infectious bronchitis virus recombinant attenuated strain, cDNA of a QX type avian infectious bronchitis virus serves as a template, after PCR amplification is conducted, infectious clone plasmids containing a QX type avian infectious bronchitis virus whole genome are constructed through a yeast homologous recombination technology, and the infectious clone plasmids are subjected to a PCR amplification to obtain the QX type avian infectious bronchitis virus recombinant attenuated strain. And co-transfecting a host cell with a recombinant plasmid carrying the QX type avian infectious bronchitis virus N protein gene and a 3'untranslated region, and then carrying out genetic rescue. The QX type avian infectious bronchitis virus recombinant attenuated strain disclosed by the invention is good in in-vitro proliferation characteristic and stable in genome heredity; the feed additive is good in safety and has no pathogenic risk to SPF chicken; the immune protection efficacy is prominent, and chicken flocks can obtain 100% protection against QX virulent virus attack after being immunized for 14 days; the method can be used for preparing vaccines.

The invention relates to the technical field of aquatic product breeding and gene engineering, in particular to a rapid all-male red crucian carp creation method and application thereof.The rapid all-male red crucian carp creation method comprises the steps that a CRISPR / Cas9 gene editing technology is utilized, a Foxl3 gene of wild type red crucian carp is knocked out in a targeted mode through double gRNA loci, an F0-generation gene knockout mutant is obtained, and the double gRNA loci are located on a third exon of the Foxl3 gene; and hybridizing the female fish in the F0-generation gene knockout mutant with the wild-type red crucian carp male fish to obtain the F1-generation all-male red crucian carp with the genotype of Foxl3 + / -. According to the method, complete separation and stable inheritance of phenotypes can be realized in the F1 generation.