628 results about "F1 generation" patented technology

The invention discloses a method for knocking out a microRNA gene family by utilizing CRISPR-Cas9 specificity, wherein a target gene is knocked out by mainly adopting a CRISPR/Cas9 system. The microRNA family is knocked out by utilizing the specificity of the CRISPR/Cas9 system for the first time; the disadvantage that only one gene can be knocked out for one time in traditional transgenosis can be overcome by utilizing the novel method; the time for establishing a model organism is reduced to three weeks; furthermore, the construction step is simple; an expensive molecular reagent is also reduced; the period for constructing a genetically modified mouse is greatly shortened to four months; multiple genes constructed for one time can be knocked out simultaneously; the fund investment is obviously reduced; F1 generations of mice can be obtained only in need of 50000 Yuan; the gene modification efficiency can be above 90%; the unreliability of the traditional technology is reduced; the operation technology is simple; and a series of complex steps including constructing a targeting vector, screening ES (Embryonic Stem) cells, selectively breeding chimeric mice and the like are unnecessary.

The invention discloses a method for breeding rmnd5b (required for meiotic nuclear division 5homolog B) gene deletion type zebra fish through gene knockout and belongs to the field of gene knockout. According to the method, construction of a gRNA expression vector and gRNA in-vitro synthesis are performed through design of a CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated 9) gene knockout target site, micro-injection is performed on an embryo of the zebra fish, the effectiveness of the target site is detected, tail cutting identification is performed, TA cloning is performed on a target sequence, plasmids are subjected to Sanger sequencing, an F1 generation of heritable zebra fish mutants is obtained, the same mutant female fish and male fish are picked from mutants of the F1 generation, hybridization is performed, an F2 generation of the zebra fish mutants is obtained, F2 generation homozygote is picked from the F2 generation of the zebra fishmutants, F3 generation pure-line inheritance is performed, and an rmnd5b gene deletion type zebra fish strain is obtained. The method is lower in off-target rate and has good medical research value inresearch of the correlation between rmnd5b gene deletion and development of other organs.

The invention discloses a method for breeding blue-lower-leg spotted-brown-feather laying hens with high egg yields. The method comprises the following steps of: artificially inseminating and mating a large quantity of Huainan spotted-brown cocks serving as male parents and Loman laying hens serving as female parents, collecting hatching eggs and hatching an F1 generation; identifying cocks and hens according to the colors of feathers and lower legs, eliminating white-feather yellow-lower-leg chicken which are cocks, reserving spotted-brown-feather blue-lower-leg chicken which are hens for serving as breeding hens, and performing back crossing by taking Huainan spotted-brown cocks as male parents to produce an F2 spotted-brown-feather generation; crossly mating and fixing the F2 generation and performing family breeding to produce an F3 generation; and performing gradual pure breeding on the F3 generation and later generations and obtaining the blue-lower-leg spotted-brown-feather laying hens with high egg yields according to egg yield, protein, lower leg color, feather color and bodily form, wherein the feathers are spotted-brown feathers; and the bodily form refers to delicate and pretty bodily form, blue lower leg and blue beak. According to the method, an appropriate high-egg-yield gene is introduced into a local chicken breed, and the proteins and macroscopic features of the local chicken breed are kept simultaneously.

The first breeding process of black-shin yellow hybrid chicken adopts pure-blood black-shin yellow chicken or synthetic black-shin yellow chicken as male parent and pure or synthetic three-yellow chicken or recessive white-feather chicken as female parent in producing the hybrid chicken. The second breeding process adopts pure-blood black-shin yellow chicken or synthetic black-shin yellow chicken as male parent and the F1 generation hybrid produced in the first process as female parent in producing the F2 generation hybrid chicken. The hybrid chicken has the outer appearance of black-shin yellow chicken as well as powerful disease resistance, fast growth speed, high egg yield, high feed converting rate and other heterosis.

The medicine for cultivating and producing dwarf green shell egg layer includes the following steps: mating cock or hem with dwarf gene with hem or cock of green shell egg chicken to generate the F1 generation; selecting hems or cocks with dwarf gene characteristic from the F1 generation; re-selecting hems or cocks with dwarf gene characteristic to generate the F2 generation; selecting and leaving hems and cocks individuals with dwarf gene characteristic from the F2 generation; and genealogy selecting and breeding, individual selection, test crossing and detection. The present invention introduces dwarf gene into green shell egg chicken variety, and can utilize dwarf gene fully and protect green shell egg chicken variety resource.

The invention discloses a preparation method of an avian influenza virus suitable for growing in a serum-free full-suspended cultured MDCK cell line and the avian influenza virus obtained through the method. The preparation method comprises the following steps of 1 preparation of the MDCK cells to be inoculated; 2 virus seed preparation, wherein a chick embryo source avian influenza virus is prepared; 3 F1 generation virus domestication; 4 F2 generation virus domestication, wherein a supernatant sample retained at the time point when the blood clotting titer of the avian influenza virus obtained in the F1 generation is highest is taken, and the step 3 is repeated; 5 F3 generation virus domestication, wherein the F3 generation virus culturing temperature is 35 DEG C; 6 F4 generation-F10 generation virus domestication, wherein the step 5 is repeated, and the domesticated avian influenza virus is obtained. According to the preparation method, through a domestication method, the avian influenza virus is directly domesticated to completely adapt to be efficiently reproduced on the serum-free full-suspended cultured MDCK cells from the mode of being cultured by a chick embryo, the domestication efficiency is high, the avian influenza virus can be efficiently infected and copied in the MDCK cells, and the virus characteristic is stable.

The invention relates to a prawn low dissolved oxygen resistance family selection method, and belongs to the technical field of prawn stress-resistance trait selection. The method comprises the steps of base population establishing; F1 generation family establishing; same pool culturing; low dissolved oxygen resistance testing; F2 generation family establishing; continuous generation selecting, wherein different sources of parent prawns are selected to establish a full/half-slib family through directional mating, common environmental breeding is performed, 94 h low dissolved oxygen stress is performed, parent selecting and remaining are performed according to the low dissolved oxygen resistance test result and the growth measure result, after four generations of continuous selection, the family of distant genetic relationship is selected from the families with excellent growth performance and strong low dissolved oxygen resistance performance, the male and female prawns which are big in individual, strong in vigor and normal in gonad development are selected to serve as parent to breed as good varieties. According to the method, the problem occurring in prawn high-density culturing that the prawns are dead caused by the fact that the prawn growth is influenced by low dissolved oxygen is solved, and the development of the prawn high-density culture industry is greatly promoted.

The invention discloses a rice genetic engineering sterile line breeding method. The method includes following steps: A, acquiring a DsRED gene expression box; B, acquiring a rice EAT1 gene expressionbox; C, amplifying corn lethal gene ZMAA1; D, amplifying corn pollen specific promoter Pg47; E, connecting gene expression elements: step 1, connecting a DsRED gene expression element onto a pCAMBIA1300 carrier; step 2, introducing a complete rice EAT1 gene onto the pCAMBIA1300 carrier where the DsRED gene expression element is already introduced in the step 1. F1-generation heterozygote abides by Mendel's law of segregation in the process of self fruiting, and generated offspring include heterozygote capable of maintaining triply linked genes and infertile sterile lines.

The invention discloses a method for creating rice engineering maintainer lines preventive against gene flow. The method includes the steps of 1, site-specifically inserting an exogenous reporter gene and a pollen lethal gene into a flanking sequence of a fertility control gene of a wild rice chromosome so as to obtain a transgenic line containing the exogenous reporter gene and the pollen lethal gene, wherein the exogenous reporter gene, the pollen lethal gene and the fertility control gene are able to closely link and inherit; 2, hybridizing wild rice and homozygous recessive rice common genic male sterile lines to obtain F1-generation plants, hybridizing the F1-generation plants as male parents to the transgenic line to obtain a generation F2, screening the generation F2 to obtain hybrid lines containing the exogenous reporter gene, namely rice engineering maintainer lines required, wherein the homozygous recessive rice common genic male sterile lines are mutant lines with the sterility control gene. The invention further discloses application of the rice engineering maintainer lines preventive against gene flow in rice breeding.

The invention discloses a method for culturing a high-quality green-shank pockmarked-feather poulard. The method comprises the following steps: (1) mating a green-shank pockmarked-feather cock with a yellow-shank pockmarked-feather hen which grows fast to produce an F1 generation; (2) back-crossing the green-plank pockmarked-feather hen of the F1 generation with the green-shank pockmarked-feather cock of the parental generation to produce an F2 generation; (3) selecting a cock and a hen which grow fast from the green-shank pockmarked-feather chickens of the F2 generation for crossing to obtain an F3 generation; and (4) selecting a cock and a hen which grow fast from green-shank pockmarked-feather chickens of the F3 generation for self-reproduction and flock enlargement to obtain an F4 generation, i.e. the high-quality green-shank pockmarked-feather poulard of the new species. The high-quality green-shank pockmarked-feather poulard cultivated by the method has the advantages of beautiful appearance, specific figure, favorable meat quality, delicious meat taste, strong disease resistance and fast growth, and is applicable to the commercial production.

The present invention relates to an excellent-quality chicken maternal strain, in particular to a method for the strain breeding of the dark-shank spotty plumage chicken with dwarf gene, which belongs to the technical field of the dark-shank spotty plumage chicken with dwarf gene. The breeding procedures of the present invention are (1) selecting a cock of Chongren chicken and a hen having the dark-shank partridge in the grandparent hen group of the dwarf yellow-feather chicken as the breeding materials and selecting a normal-shaped cock having the dark-shank partridge character in the F1 generation after the hybridization of the cock and the hen; (2) Selecting the dark-shank partridge normal-shaped cock to be mated with the hen of the dark-shank partridge dwarf yellow-feather chicken and selecting the dark-shank partridge dwarf cock and the dark-shank partridge dwarf hen in the F2 generation; (3) cross-breeding and locking the selected dark-shank partridge dwarf cock and the dark-shank partridge dwarf hen so as to get the present invention after the breeding from generation to generation. Since the body of the maternal-strain chicken is short cultivated through the present invention, the chicken has the outstanding advantages of precocious puberty, high-yield of eggs and less feed consumption and cultivated space saving, which greatly reduces the production cost of the commodity generation chicken and improves the comprehensive benefit of the cultivation.

The invention discloses a method for distinguishing conventional cotton and hybrid cotton in an assistant mode and a special kit thereof. The method for distinguishing the conventional cotton and the hybrid cotton in the assistant mode comprises the following steps of (1) extracting a genomic DNA of cotton to be distinguished; (2) respectively carrying out PCR amplification on each pair of primers in the kit by using the genomic DNA of the cotton to be distinguished as a template to obtain the spectrums of PCR amplification products of each pair of the primers; and (3) detecting spectrums of the PCR amplification products of each pair of the primers. Proved by experiments, the kit, an SSR spectrum and the distinguishing method can effectively, accurately and quickly distinguish the cotton to be tested to be the conventional cotton or the hybrid cotton and a cotton seed to be tested to be an F1 generation or an F2 generation, thus the kit, the SSR spectrum and the distinguishing method have wide application prospect.

The breeding process of high-yield variety with green (black or yellow) shank and recessive white feather includes the following steps: hybridization between recessive white feather chicken or green (black or yellow) shank and recessive white feather chicken and high-yield brown-shell egg or white-shell egg chicken to obtain F1 generation hybrid individuals; selfing reproduction of F2 generation with the F1 generation and selecting green (black or yellow) shank and white feather chicken W; test crossing green (black or yellow) shank yellow chicken with W, selecting green (black or yellow) shank and pure white feather hem and cock and self-reproduction to produce Y; repeated test cross and selection to obtain recessive white feather chicken individuals; and self-reproduction to expand colony, constitute genealogy and obtain new chicken variety of high-yield variety with green (black or yellow) shank and recessive white feather.

The invention discloses a method for increasing 3-4 generations of winter wheat filial generation in one year by utilizing climatic conditions. The method comprises the steps of: firstly carrying out dormancy breaking treatment on current-generation hybrid F0, breeding in field while shielding with 1-2 layers of sunshade nets, harvesting to obtain F1 generation, carrying out pot culture on seeds F1 in outdoor natural conditions, breeding with potted seeds F1 to obtain seeds F2 generation, breeding with the wheat seeds F2 generation to obtain seeds F3 generation, and finally breeding with the seeds F3 generation in peak with elevation of 1500m in north to obtain wheat seeds F4 generation. By adopting the steps, 4 generations are increased within a year and a half, the investment is low and the cost is low, thus a new way is explored for routine breeding, in-situ generation increasing and rapid planting of the wheat.

A method for selectively culturing the new variety of wheat includes such steps as respective crossing between the wheat 'Aibai' as female parent and 15-20 excellent varieties as male parent to obtain F1 generation, respective backcrossing between the dwarf sterile plants as female parent and the said male parent to obtain the backcrossed seeds F1, mixing them together, free pollination between fertile plants and sterile plants to obtain the seeds, mixing, free pollination between dwarf sterile plants and non-dwarf fertile plants to obtain seeds A, controlled pollination between the high-quality dwarf sterile plants as female parent and the specific plants as male one to obtain seeds B, proportionally mixing seed A with B, repeating said steps to obtain improved group, and culturing the excellent fertile plants by genealogical method.

The invention discloses a breeding method for hybrid rice and belongs to the breeding field of hybrid rice. The breeding method for hybrid rice disclosed by the invention comprises the steps: improving a rice sterile line with small grain rice germplasm to obtain a small grain sterile line which is excellent in agronomic characters; improving a rice restorer line with large grain rice germplasm to obtain a large grain restorer line which is stable in agronomic characters; and then carrying out test-mating on the small grain sterile line as a female parent and the large grain restorer line, planting a test-mating F1 generation, and selecting a hybridized combination which is excellent in character to obtain the hybrid rice. The rice length of the small grain sterile line obtained by breeding is smaller than the rice width of the large grain restorer line, so that a male parent and a hybrid can be quickly and efficiently separated, and the breeding method is suitable for mixed sowing and production of hybrid seeds and/or mechanical operation, and the efficiency and incoming of production of hybrid seeds are improved, and the cost is lowered.

The invention relates to a breeding method of high-yield new-breed of silver-feather chickens laying green-shell eggs. The method includes the following steps that firstly, a hen laying eggs with green shells and a parent-generation female parent cock of a chicken, hatched in an automatic sexing mode, having gold and silver feathers and laying high-yield eggs with red shells are selected from local chicken breeds and are subjected to hybridization to obtain F1 generations; secondly, the F1 generations are subjected to crossing, purely-white-feather cocks and purely-white-feather hens laying eggs with green shells are selected from F2 generations, and self-breeding and breed enlarging are carried out; thirdly, test mating and identification are carried out on hens having purely-white feathers and laying eggs with green shells and cocks with purely-white feathers in later self-breeding generations by a cock having yellow-red feathers and laying eggs with brown shells and a hen having yellow-red feathers and laying eggs with brown shells respectively, individuals of which cock and hen green shell and silver feature genes are homozygotes are selected out, and self-breeding and breed enlarging are carried out; fourthly, the third step is repeated until stable inheritance of sliver feather and green shell characters is achieved; fifthly, the fourth step is repeated until a high-yield new breed of chickens having silver feathers and laying eggs with green shells is obtained. By means of the method, the egg yield can be substantially increased, two-way crossing can be carried out between the high-yield new breed as a female parent and other breeds, and the automatic sexing rate, green shell rate and the like of later generations can reach 100%.

The invention discloses a method for breeding high-yield japonica rice species capable of efficiently preventing rice blast. The method comprises the following steps: (1) hybridizing a rice blast preventing parent with a high-yield parent to obtain a hybrid F1 generation, planting the hybrid F1 generation, and harvesting the F2 generation seeds; (2) sowing the F2 generation seeds in the planting area in a proper time, and selecting the single plants to obtain F3 generation plants; (3) mixing the selected F3 generation plants, threshing, sowing in a proper time, planting single plants, in the booting stage, using the rice blast mixed bacterium liquid in the area which is suitable for promotion of the species to carry out inoculation, and choosing the single plants to obtain the F4 generation plants; (4) choosing segregation generation more than F4 generation, choosing the plants, and obtaining the seeds of target species. According to the method, a rice blast inoculation technology and a high-yield species small area selecting technology are organically combined; the rice blast resisting gene and high-yield gene are effectively combined; the yield level and the resistance level are both enhanced, the vitality of the novel species is improved, and the rice blast resistant level of the novel species is effectively enhanced at the same time.

The invention discloses a seed production method for a hybrid pepper variety. The seed production method comprises the following steps of: manually removing an anther of a pepper female parent, collecting pollen of a peeper male parent, and carrying out artificial supplementary pollination on the pepper female parent, wherein the produced F1 generation seed is a hybrid seed; the step of manually removing the anther of the pepper female parent is carried out through adopting a manual rotation method; the manual rotation method comprises the following steps: a joint position between a pedicel and a receptacle is pinched by a left hand; a position, where is close to the receptacle, of a corolla is gently pinched by a thumb and a forefinger of a right hand; and the thumb and the forefinger slowly twist, so that the corolla and the anther are removed, and a style and an ovary are exposed. A female parent emasculation method (manual rotation method) disclosed by the invention has the characteristics of saving labor and force, capably reducing production cost, realizing thorough emasculation, and capably ensuring emasculation quality; and a stamp-pad ink marking method is adopted by the invention, and the stamp-pad ink cost is low, so that the production cost can be reduced, as well as labor and force are saved. The conventional marking method is an iron ring marking method; the ironring marking method is realized through bonding an iron ring on a pollinated stalk, so that the operation cost is high; and the iron ring has a certain weight, so that flowers are easy to fall off, therefore the yield is low.

This invention relates to a molecule marking method of selecting cotton yields and properties or fiber qualities using SSR technology, which includes: a) cross-fertilization of Sino-G97038 cotton group with the 16th group from China Institute of Cotton (Sino-16), with its F1 generation selfing to produce the F2 generation; b) extraction of the whole DNA in the leaves of F2 (Sino-G97038í‡Sino-16) separate group by means of CTAB; c) establishment of target character extremum bank by means of BSA; d) selection of parent species with SSR primers, further selection of discrepantly behaving primers between parent species with established extremum DNA bank, and amplification of the obtained discrepant primers and all F2 individual plants so as to gain polymorphism markers; e) SSR amplification and detection; f) data analysis. This invention publishes the molecular markers of the cotton fiber qualities, which have a nucleotide sequence from SEQ ID No.1 to SEQ ID No.4. Besides, it also publishes the application of the molecular markers of cotton yield and properties and fiber qualities in seed breeding.

The invention discloses a method for preparing corn type II embryogenic calli. With the method, a corn inbred line which can produce type II embryogenic calli can be prepared. the method comprises the flowing steps: carrying out selfing among an initial corn inbred line to obtain seeds of an F1 generation; carrying out embryogenic callus induction upon embryos of the F1 generation seeds, such that embryogenic calli are obtained; collecting type II embryogenic calli; carrying out regenerating and cultivating upon the type II embryogenic calli until corn plants are obtained. The obtained corn plants form a target corn inbred line. With type II callus phenotype, the corn material provided by the present invention is easy to regenerate, and the regenerated plants have excellent agronomic properties. According to the present invention, a novel material for present transgenic acceptors is provided, a limitation that presently only non-inbred line Hill are utilized is solved, and the period for cultivating new species of corn by using transgenic technologies is shortened.

The invention relates to the field of chicken breeding, in particular to the matching technology field of slow type special-high quality ma chickens. The ma chickens comprise a progenitor generation, a parent generation and a commodity generation. The matching method comprises the steps that in the progenitor generation, Qingyuan ma cocks and hens, Guangxi ma cocks and slow type recessive white hens are used for constituting a first paternal line and a first maternal line; in the parent generation, the Guangxi ma cocks and the recessive white hens are crossbred to obtain F1 generation chickens; in the commodity generation, the Qingyuan ma cocks and F1 generation hens are crossbred to obtain F2 generation slow type special-high quality ma chickens. According to the chickens bred through the method, the body form of the special-high quality chickens can be kept, the taste of eating chicken and eggs can also be kept, the amount of consumed feed is lowered, the disease resistance capacity is improved, compared with traditional Guangxi ma chickens, the egg laying capacity of the parent generation is improved by more than 25%, the growing speed of the commodity generation is improved by more than 20%, feeding cost is lowered, and the profits of breeding the chickens is increased.

The invention discloses a preparation method of a rice genetic engineering sterile line. The preparation method comprises the following steps: by using the Afl2 restriction Enzyme cutting sites introduced to the upstream and downstream, connecting the corn lethal gene ZMAA1, through a single restriction Enzyme cutting site, to a pCAMBIA1300 binary vector already connected with a DsRED gene expression element and the rice EAT1 gene. The restriction enzyme cutting sites Kpn I and Sma I introduced into the upstream and downstream primers and the restriction enzyme cutting sites Kpn I and Sma I onthe pCAMBIA1300 binary vector are utilized. According to the method disclosed by the invention, the F1-generation hybrid conforms to the Mendel's law of segregation in the self-seed process, and theoffsprings include the hybrids capable of maintaining the triple-linked genes, as well as the sterile line without fertility.