101results about How to "Efficient breeding" patented technology

The present invention relates to a site-directed knockout system for a rice TMS10 gene, and applications thereof. The site-directed knockdown system comprises a CRISPR / Cas9 system and a sgRNA target, wherein the sgRNA target is the sequence containing PAM or NGG in a rice male sterile gene TMS10, the CRISPR / Cas9 system is CC-TMS10-1, and the CC-TMS10-1 target sequence is a SEQ ID NO.1 sequence from site 2281 to site 2299. The applications comprise carrying out targeted knockout on the TMS10 genes of different japonica rice varieties and different Indica rice varieties by separately using CC-TMS10-1, wherein the experiment results prove that the heterozygous mutation transformation plant produced through the site-directed knockout induction in different rice varieties shows the temperature sensitive male sterility characteristic. According to the present invention, the site-directed knockout system provides the efficient breeding method for the creation of the temperature sensitive male sterile line germplasm resources based on the rice temperature-sensitive male sterile gene TMS10 and the rice hybridization breeding.

The invention discloses a hormone-free rapid tissue culture and propagation method of Emei roxburgh anoectochilus terminal bud seeds. According to the hormone-free rapid tissue culture and propagation method, no hormone is used in the whole process, the mature and non-cracking fruits, which is pollinated for 5 months after flowering, of wild or artificially planted roxburgh anoectochilus terminal bud distributed in Szechuan Emei region are taken as the material, and seedlings are bred efficiently and quickly according to the route from seeds to protocorms, complete plants and acclimatization and transplant. A hormone-free culture medium is adopted in the whole process; more than 5000 good-quality seedlings can be quickly bred from one mature fruit by virtue of tissue culture of about 10-12 months, and after acclimatization and transplant, the greenhouse culture survival rate can be above 95%. According to The hormone-free rapid tissue culture and propagation method of the Emei roxburgh anoectochilus terminal bud seeds is capable of keeping the good traits of the Emei roxburgh anoectochilus terminal bud and maintaining the good medicinal properties of the Emei roxburgh anoectochilus terminal bud; besides, the method is simple, and the cost is low; industrialized seedling production can be realized; no hormone is adopted so that the safety of the seedlings can be ensured; the hormone-free rapid tissue culture and propagation method has important significance on regeneration and sustainable utilization of critically endangered valuable and rare resources of medicinal plants and protection of seed resources.

The invention discloses a method for fixed point knock-out of the second exon of rice OsPDCD5 gene by using a CRISPR / Cas9 system. The method comprises the following steps: selecting a target fragment in the second exon region of the rice OsPDCD5 gene, constructing a plant CRISPR / Cas9 recombinant vector, introducing the plant CRISPR / Cas9 recombinant vector to rice calluses through an Agrobacterium infection technology, carrying out regeneration to form seedlings, shearing double strands of the second exon of the OsPDCD5 gene under the combined action of guide RNA and Cas9 nuclease, and realizing random insertion or random deletion of the target gene fragment through the self DNA repairing function of cells. Nine strains with the target fragment having point mutation are obtained through a PCR amplification sequencing technology, and pass phenotype identification, so the purpose of the increase of the plant height and the yield of rice is realized. The method provides an efficient breeding way for cultivating high-yield and high-quality rice varieties.

The invention relates to a method for breeding carp quickly and efficiently. The method is characterized by comprising the following culture steps of: establishing 80 first breeding families by taking carp and Yellow River carp as basic breeding colonies, hatching fish fry in net cages and performing early culture; injecting radio frequency marks into abdominal cavities of 50 fish fry selected from each family by using a syringe and individually marking; evaluating the breeding value of each fish fry by using ASReml software and according to a BLUP method; performing matched breeding on male fish with the evaluated breeding values in the first ninety places and female fish with the evaluated breeding values in the first ninety places, and establishing second breeding families; performing matched breeding on 20 male fish with the evaluated breeding values closest to 0 and 20 female fish with the evaluated breeding values closest to 0, and establishing second control families; and after the female fish are matched with the male fish, transferring fish nests with oosperms into hatching net cages to hatch to obtain the second generation of fish fry. By the method, the carp can be bred quickly and efficiently; inbreeding depression is avoided; and breeding can be performed for a long time.

The invention relates to a rapid and efficient method for breeding tilapias, which is characterized by comprising the following steps of: utilizing GIFT strain Nile tilapias of 60 families introduced from the Malaysia Worldfish Center as a basic breeding colony; separating tilapia fries of different families into different net cages for breeding; respectively selecting 30 fries from each family, and injecting a radio frequency identification to a fry abdominal cavity with an injector to identify individuals; breeding the fries before a propagation season of the next year, and measuring body weight, body length, body height and body thickness data of all identified tilapias; estimating a breeding value of each fringetail according to a BLUP (Best Linear Unbiased Prediction) method by utilizing ASREML software; selecting male tilapias with the estimated breeding values of the top 60 and female tilapias with the estimated breeding values of the top 120, and carrying out nest mating propagation in the ratio of 1:2 of the male tilapia to the female tilapia to establish a family of the second generation; taking out oosperms from the oral cavity of the female tilapia which spawns, and transferring the oosperms into a hatcher to carry out hatching of running water. The rapid and efficient method for breeding the tilapias can avoid the problem of inbreeding depression caused by inbreeding, thereby being capable of carrying out breeding for a long period of time.

The invention discloses a colony-family-molecule comprehensive genetic breeding method for takifugu obscures. The colony-family-molecule comprehensive genetic breeding method for takifugu obscures comprises the following steps: firstly, continuously selecting and breeding for four generations, after selecting and breeding the colony, taking two colonies with obvious segregation of character as the basis selecting and breeding colonies for the next generation for family selecting and breeding, adopting a molecular marker technology for establishing the assistant family, breeding solely after the generation of each family parent, establishing the basis colony taking the family as the unit and forming a larger production unit, selecting and breeding for each independent production unit, selecting for six time during three breeding stages, in the marketable fish breeding stage and before the maturing stage, and repeatedly performing the steps for selecting and breeding the nest generation. The colony-family-molecule comprehensive genetic breeding method for takifugu obscures has the advantages that the advantage parent can be effectively selected, the molecular marker technology is adopted for executing the genetic analysis, the genetic conditions of the parent before the breeding stage can be understood for guiding the parent pairing and combining the scientific research with the production, the advantage individual in the family can be effectively selected, and the optimization breeding and the resource utilization can be achieved.

The present invention relates to a feed composition which contains silver-carrying zeolite and an animal-breeding method comprising the step of administering, to an animal, the foregoing silver-carrying zeolite-containing feed composition. The feed composition has almost no influence on the useful lactobacillus, but exerts an antimicrobial effect on various kinds of harmful microorganisms, in particular, bacteria belonging to the genus Salmonella or the like. Accordingly, the feed composition would permit the improvement of the healthiness of enteric canal of domestic animals, domestic fowls and cultivated fishes and the composition would in thus permit the acceleration of their growth, while maintaining their good healthiness.

The invention relates to a method to cultivate preharvest sprouting resistance hybrid rice sterile line by molecular marker-assisted selection. The steps of the invention are that: step A, hybridization, backcrossing and self crossing are performed by using a preharvest sprouting resistance variety as donor parent and the corresponding maintainer line of sterile line having high combining ability but with easy pre-harvest sprouting as recurrent parent; meanwhile the donor parent and the recurrent parent are planted at every season; when choosing among various segregating generations, two microsatellite labeled primers RM447 and RM3754 are used to introduce molecular marker-assisted selection; a plurality of key strains are acquired after two or three generations of backcrossing and five to seven generations of self crossing; step B, the acquired key strains of step A and the sterile line having high combining ability but with easy pre-harvest sprouting are backcrossed for four to seven generations in pairs; during the backcrossing process, the same method of molecular marker-assisted selection as step A is used in selection, then the preharvest sprouting resistance hybrid rice sterile line is cultivated. The invention has the advantages that preharvest sprouting resistance material can be fast and effectively selected; the breeding scale is reduced; the breeding cost is lowered; the preharvest sprouting resistance hybrid rice sterile line is fast selected and bred with high efficiency.

A feeding method and apparatus for breeding natural enemy insects necessary for establishing a farming system that uses less or no pesticides and a rearing method for breeding natural enemy insects are provided.A feeding apparatus including a food supplying section, a feeding section, and a food introducing section via which the food supplying section and the feeding section are in communication with each other, and an attracting section made of a material having a specific color tone is designed, and is used to breed natural enemy insects.

The invention discloses a cultivating method for arundina chinensis and an application thereof. The cultivating method comprises the following steps: picking the arundina chinensis capsule which growsfor 28-30 days after the fertilization, and performing the aseptic insemination; and transplanting obtained protocorm in a subculture growth medium, inducing the protocorm to grow and sprout rapidly,using an LED as a tissue culture light source, and performing the red-light and blue-light combined cultivation according to the proportion of 2-4:6-8; transplanting aseptic seedlings of which the height is more than 7 cm in a greenhouse, and performing the cultivation management. The method is capable of determining the optimal culture conditions in the subculture process after the seed germination of the arundina chinensis, wherein the optimal culture conditions comprise LED light quality and light intensity and treatment time, effectively promoting the accumulation of plant chlorophy, thethickening of stems and the extension of root, and saving the production cost and period. The seedlings can be directly transplanted after the subculture without the strong seedling and rooting process. Especially, the LED promote the flavonoid and phenolic substance accumulation of active ingredients in the arundina chinensis, the oxidation resistance of plants is remarkably improved, and the method has the important significance to the medicinal plant cultivation.

An efficient young rabbit breeding method for meat rabbits includes the steps of parent selection, a female rabbit oestrus mating method, feed management in a breeding stage and main disease prevention and control in the breeding stage. The method includes the particular steps that New Zealand male rabbits which are 2-3 years old and California female rabbits which are 2-3 years old are selected by the ratio of 1:6-1:8 and raised separately in different chambers; the male rabbits and the female rabbits mate freely during the oestrus stage of the female rabbits, and after the female rabbits are pregnant, the male rabbits and the female rabbits are separated; 1-2 days after delivery, young rabbits and the female rabbits are separated and nursed by the female rabbits once every day on time, the young rabbits start to eat feed after 10-15 days and are weaned after 30-35 days, it is prevented that the nursing female rabbits come down with digestive tract diseases to infect the young rabbits, the feed is prepared from hay meal, corn flour, wheat bran, bean pulp, fish meal, calcium hydrophosphate and calcium hydrophosphates in a matched mode, and unqualified and mildewing feed is eradicated; acariasis prevention and control is performed, a rabbit hutch should be clean and sanitary and disinfected at regular intervals, after coming down with the diseases, the rabbits are treated in time with ivermectin injection for 1-2 times each week, the rabbits attacked by the diseases already are isolated for treatment, and abamectin is used for scrubbing the affected parts.

The invention provides a maize variety distinguishing method and system based on a three-dimensional phenotype of a maize tassel. The method comprises the following steps: marking a plurality of feature points around a target maize tassel, and collecting images of the target maize tassel at multiple viewing angles; constructing a three-dimensional model of the target maize tassel according to theimages under the multiple viewing angles; obtaining three-dimensional phenotype parameters of the target maize tassel based on three-dimensional model, wherein the three-dimensional phenotype parameters comprise an outer envelope volume, a total area of branch vertical projection, a plane aggregation degree, a space aggregation degree, a spindle variation coefficient, a crown-height ratio, a head-stem ratio and a gravity center; and distinguishing the maize variety of the target maize tassel according to the three-dimensional phenotype parameters. According to the method and system, the three-dimensional phenotype parameters of the maize tassel are scientifically from the three-dimensional perspective, and the maize varieties are accurately distinguished by using the difference of the three-dimensional phenotype parameters of different maize varieties, which is conducive to accelerating the maize breeding progress, and effectively improving the breeding efficiency and level.

The invention discloses an efficient breeding method for families of Portunus trituberculatus and belongs to the field of fishery breeding. According to the method, different wild geographical populations of the Portunus trituberculatus are collected, parent crab mating is completed with a manually controlled directional mating technology, after mating, large pincer muscles of male crabs are taken and stored at the ultralow temperature being subzero 80 DEG C, mated female crabs live through the winter and discharge the young, families are constructed, and after discharging of the young, large pincer muscles of the female crabs are taken and stored at the ultralow temperature being subzero 80 DEG C; when the young of the families develop to young crabs in the stage II, the young crabs are transferred outdoors for breeding, all the families are mixed in the equal proportion for releasing, test populations are established, and meanwhile, a conservation population is established for each family; at the 120-day age, growth traits of each individual of the test populations are measured, then family identification is performed on the individuals by the aid of screened micro-satellite primers, and statistics about survival rates and the growth traits of the families is performed; comprehensive indexes are calculated according to the survival rates and the growth traits of the families, breeding of the families is performed, reservation families are required, individual selection from the families is performed on conservation populations, parent crab mating is completed with an indoor manual directional mating technology, and accurate breeding of the families is realized.

Belonging to the field of biotechnology and crop genetic engineering technology, the invention discloses a rice seed dormancy regulation gene OsMPK14 and application thereof. The rice seed dormancy regulation gene OsMPK14 disclosed by the invention plays an important role in improving rice seed dormancy, has a sequence shown as SEQ ID NO.2, and encodes a protein with amino acid sequence shown as SEQ ID NO.1. The application specifically includes CRISPR / Cas9 systematic editing, interference or knockout of OsMPK14 gene and destruction of the biological functions of OsMPK14 gene so as to obtain apreharvest sprouting resistant rice strain. The gene OsMPK14 knockout method provided by the invention can knock out the OsMPK14 gene of the existing material, by screening the knockout offspring, adormancy enhanced rice strain can be obtained, and the preharvest sprouting resistance can be effectively improved.

The invention discloses a cuttage method for quick rooting of nepenthes. The method comprises the following steps that 1, nepenthes branches on nepenthes stock plants are cut off, and cuttage branchesare obtained; S2, the cuttage branches are cut into a medium in a greenhouse, and the medium comprises peat soil, ardealite, silicon powder and nutrient soil; a preparation method of the nutrient soil comprises the following steps that 1, after clam shells are evenly mixed with tourmaline powder, first powder is obtained through calcination; 2, pig manure, wormcast and fermentation liquid are mixed and fermented to obtain yeast; 3, wild radix asparagi, rhizoma arisaematis and garden balsam stem are mixed and put into an ethanol solution, and filtered liquid and filtered residues are obtained;4, the first powder, the yeast, the filtered liquid and the filtered residues are evenly mixed to obtain the nutrient soil. According to the cuttage method of nepenthes, the clam shells are smashed and subjected to multi-segment warming treatment, so that the nutrient soil is good in air permeability and high in water retention and fertilizer retention capacity, it can be guaranteed that nepenthes has sufficient water in the cuttage process, and the survival rate of nepenthes in the cuttage process is increased.

The invention provides a rapid breeding method of the seed of konjac, namely a method for sexual reproduction through apomixis, thus the seed of konjac is a small bulb. The reproduction rate of konjacseed bulbs is not more than 5-7 times in the way of digging big and staying small and large bulb-cutting propagation. According to the rapid breeding method of the seed of konjac, a seed bulb can breed 800-1500 seed bulbs, and the reproduction ratio is close to 1500 times, so that the problem of low breeding coefficient and degradation of seed source in konjac industry is solved. The rapid breeding method of the seed of konjac has the advantages of high breeding efficiency, keeping seed character, preventing and controlling seed source degeneration, fast breeding of konjac bulbs for farmers to grow, thereby producing more konjac bulbs to meet the market needs.

A method for selecting cabbage-type rape varieties and materials by a rape double haploid inducing line includes 1), determining target traits of breeding of cabbage-type rape varieties and materials; 2), performing crossing, convergent crossing or backcrossing on at least two cabbage-type rapes with the target traits; 3), pollinating cross, convergent cross or backcross descendants by the rape double haploid inducing line; 4), inducing the descendants to overcome self-incompatibility, and verifying genetic stability of the induced descendants; 5), verifying yield, resistance and quality characters of the induced stable descendants; 6), according to the yield, the quality characters and the resistance, determining stable strains to form conventional varieties of the cabbage-type rapes; 7), inducing the genetic stable strains of the descendants to form a new variety line of the cabbage-type rapes, and test-crossing the new variety line with a sterile line to form a maintainer line or restorer line, or entering a next circle of variety and material breeding process. By the method, breeding speed and efficiency of hybrid or conventional varieties of the cabbage-type rapes can be increased greatly, and manpower and material resources can be reduced.

The invention discloses a breeding method of a main-inflorescence multi-silique brassica napus type conventional rape variety. The breeding method comprises the following steps: (A) carrying out hybridization by taking main-inflorescence multi-silique brassica napus type rape CGMCC NO.12262 as a male parent and brassica napus type rape strain as a female parent, thus obtaining hybrid progeny F1; (B) carrying out backcrossing by taking the hybrid progeny F1 as a non-recurrent parent and the brassica napus type rape strain as a recurrent parent, thus obtaining backcross progeny; (C) carrying out backcrossing by taking the backcross progeny as a non-recurrent parent and the brassica napus type rape strain as a recurrent parent, thus obtaining backcross progeny; (D) carrying out self-cross on the backcross progeny, thus obtaining the main-inflorescence multi-silique brassica napus type conventional rape variety. Conventional rape varieties having the character of having multiple siliques on the main inflorescence can be bred by utilizing the breeding method disclosed by the invention, and the conventional rape varieties can be used as rape varieties which are suitable for simplified and high-density planting.

The present invention relates to an escherichia coli mutant strain with high cytidine production and a method for fermentation production of cytidine, and belongs to the technical field of fermentation. The escherichia coli mutant strain is obtained by mutagenic screening and has the following characteristics: 1, alanine at 182nd position of carbamyl phosphate synthetase is mutated to valine, andserine at 948th position is mutated to phenylalanine; 2, isoleucine at 86th position, glycine at 93rd position and cysteine at 109th position of aspartic acid carbamoyl transferase regulatory subunitare deleted; 3, asparagine at 72nd position of uridine kinase is mutated to alanine and aspartic acid at 159th position is mutated to asparagine; and 4, aspartic acid at 147th position of cytidine triphosphate synthase is mutated to glutamic acid, and glutamic acid at 149th position is mutated to alanine. The mutant strain is fermented in a 50-L fermentation tank, cytidine yield reaches (90 plus or minus 2) g / L, sugar-acid conversion rate reaches (30 plus or minus 1)%, and the cytidine yield and sugar-acid conversion rate are both the highest values reported.

The invention belongs to the field of seedling culture, and relates to a method and device for high-yield hydroponic seedling culture of pinellia ternate, which realize high-efficiency hydroponic production of pinellia ternate seedlings through the steps of pinellia ternate seed stem culture, hydroponic seedling culture, harvesting, hydroponic seedling culture and the like. According to the hydroponic culture method, under the controllable environment condition, illumination and nutrient solution circulation are automatically controlled, and three-dimensional multi-layer planting and efficient breeding of pinellia ternate seedlings are achieved.

The invention provides an automatic seedling raising device for spherical vegetable seeds. the automatic seedling raising device for spherical vegetable seeds comprises a support assembly, a transmission assembly, a hole pressing assembly and a seed putting assembly; the support assembly comprises a concave frame; the transmission assembly comprises two rollers which are symmetrically arranged bilaterally, a belt is installed on the two rollers in a matched way, and holed trays are placed on the belt; the hole pressing assembly comprises a hole pressing plate, a guide rod is arranged in the middle of the top face of the hole pressing plate, and a lifting assembly is installed at the rear end of the guide rod in a matched way; a discharging assembly comprises a hopper, a suction column is arranged below the hopper, four suction hole groups are uniformly distributed in the surface of the suction column in the circumferential direction, a driving assembly is installed at the end of the suction column in a matched way, and air pipes are also installed at the two ends of the suction column in a matched way. Compared with the prior art, the automatic seedling raising device has the advantages that integrated operation of transmission, hole pressing and seed putting is realized, the automation degree is high, seeds can be rapidly, accurately, efficiently and stably bred, the breedingefficiency is greatly improved, and the labor cost is saved.

The invention relates to a vegetative propagation method, in particular to an efficient bud grafting and reproduction method for ligustrum compactum ait. The efficient bud grafting and reproduction method for the ligustrum compactum ait comprises the following steps: selecting 1 to 2-year-old ligustrum compactum ait seedlings as stocks, cutting off the stocks in a manner of being parallel to the ground, and selecting a new branch as a bud grafting acceptor; selecting an annual branch of a plant which is 5 or more years old as a reproduction material; in the middle of March and the middle of August, performing grafting operation by adopting a peltate bud grafting mode; and after the grafting, performing film removal, stock cutting, fertilization, binding, bud picking, weeding and watering management. Extreme low-temperature freeze injury is prevented in winter. The survival rate of the ligustrum compactum ait reproduced by the method is 96.1 percent or above, and the tree seedling rate is 98.0 percent or above; furthermore, the ligustrum compactum ait can keep qualified characters of a mother plant, and the plant grows well in the later stage; the advantage is obvious, and the greening effect is stable; and the efficient bud grafting and reproduction method meets a large-area popularization and application demand.

The invention discloses a method for deleting a selective marker gene of a transgenic poplar. The method comprises the steps of first placing a transgenic poplar test tube plantlet on a culture medium M to carry out secondary propagation in a root sprouting manner; scissoring leaf discs to be cultured; and then immerging into an Agrobacterium tumefaciens EHA105 (Ethyl Hexyl Acrylate 105) bacteria liquid with pX6-GFP (p-Xylene 6-Green Fluorescent Protein)) plasmids to be dipped for 10-15 minutes; culturing to obtain a complete plant after removing the bacteria liquid; and culturing in a culture medium containing beta-estradiol until the plant is reproduced after finishing the scissoring the whole plant stem. In the method disclosed by the invention, by using the beta-estradiol added to the culture medium, a callus is formed by inducing the transgenic plant stem until the selective marker gene is deleted in the plant reproducing process; and a poplar transgenic system without the selective marker gene is established by using a recombinant deleting function of the Cre / lox (locus of X-over) system to provide a new way for culturing a new variety of the transgenic poplar with biosafety and lay the basis for safe and high efficient forest transgenic breeding.

The invention discloses a fast rooting method for cuttings of camellia japonica, comprising the following steps: S1, selecting side branches on the mother tree of camellia japonica and girdling them, soaking them in indole butyric acid solution to obtain cutting branches; S2, cutting the cutting branches The cuttings are inserted into the matrix, and the matrix is ​​peat soil, phosphogypsum, silicon powder, and nutrient soil; the preparation method of the nutrient soil includes the following steps: Step 1, after crushing the barnacle shells, soak them in hydrogen peroxide solution, filter, and add electric The stone powder is mixed evenly and calcined to obtain the first powder; step 2, the pig manure, vermicompost, zucchini seeds, and fermentation liquid are mixed evenly, and fermented to obtain a fermented product; step 3, the first powder, fermented product, aspartic acid , sodium naphthalene acetate and mix evenly to obtain nutrient soil. In the method for cutting Camellia japonica of the present invention, the matrix contains nutrient soil, which is generally porous and loose, has good air permeability, and has a strong ability to retain water and fertilizer. During the cutting process, sufficient water for Camellia japonica can be maintained, and the survival of camellia japonica during the cutting process can be improved. Rate.

The present invention relates to an artificial microalgae strain breeding method, which comprises normal pressure and room temperature plasma mutagenesis of microalgae strains and algae strain screening based on absorbance and specific dye luminescence intensity change. The artificial microalgae strain breeding method is characterized in that the normal pressure and room temperature plasma mutagenesis technology, the microalgae growing testing based on absorbance, and the microalgae grease evaluation method based on the fluorescent dye are combined, and the artificial microalgae strain breeding method has characteristics of efficient and rapid target algae strain obtaining compared with the existing microalgae strain breeding method.

The invention discloses an Indel molecular marker for identifying novel single fasciated inflorescence of capsicum annuum L., a primer and application. Four parts of highly-homozygous selfing lines are utilized for constructing two F2 populations (CS,SY). A method of bulked segregant analysis (BSA) and a method of chain positioning are utilized for obtaining a chromosome region and a candidate gene which are closely linked to the fasciated inflorescence of the capsicum annuum L., and the molecular marker is further developed according to variations of nearby close linkage of the candidate gene. The marker is utilized for conducting genotype identification on the two F2 populations CS and SY, wherein the coincidence rate in the CS reaches 100%, and the coincidence rate in the SY reaches 94%. The research result helps to supply methods for identifying structural types of the inflorescence of the capsicum annuum L. and achieve molecular assisted breeding, and a foundation is provided forcontrolling map-based cloning of genes of the novel fasciated inflorescence of the capsicum annuum L. and analyzing a molecular mechanism formed by the fasciated inflorescence.

The invention discloses a method for creating a red rice strain by targeting a Rc gene by using a gene edition technique. The method comprises the following steps: editing sequences of a rc gene frameshift mutation point by using a gene edition technique, screening and collecting an RC genotype with function recovery, and successfully improving rice colors of two materials, namely nonglutinous rice Gangyou 8518 and japonica rice Xiushui 134. By adopting the method, an efficient breeding mode is provided for creating red rice germplasm resources and culturing excellent red rice varieties.

A natural yeast extract which is rich in glutamic acid and therefore has an impact at first taste. Further, provided is a yeast extract which is also rich in 5′-guanylic acid or 5′-inosinic acid and therefore has strong umami. Further, provided is a yeast mutant capable of accumulating a large amount of glutamic acid, glutamine and ribonucleic acid for obtaining such a yeast extract. A yeast mutant to which resistance to organic acids and analogues thereof has been imparted by inducing spontaneous mutation, accumulates a significant amount, i.e., 10% by weight or more of the total of free glutamic acid and glutamine in the cell, and further accumulates 5% by weight or more of a ribonucleic acid. The yeast extract produced by using this strain contains 20% by weight or more of L-glutamic acid, and further contains 3% by weight or more of 5′-IG.

The invention provides a high-throughput screening method for fast-growing type acid-producing strains of ketogulonigenium vulgare, and belongs to the technical field of microbial strain breeding. According to the high-throughput screening method, the ketogulonigenium vulgare subjected to mutagenic treatment is cultured on a solid medium panel, a certain dose of an indicator is added to the solid medium, and simple and fast identification for the fast-growing type acid-producing strains of the ketogulonigenium vulgare is realized; according to design, the selected fast-growing type acid-producing strains of the ketogulonigenium vulgare are inoculated to a strain liquid medium for culturing, a certain dose of the indicator is added to the strain liquid medium, simple and fast determination for the selected fast-growing type acid-producing strains of the ketogulonigenium vulgare is realized, then the indicator identification is combined with a centrifuge tube group culture technology, and the batch culturing effect is realized while the requirement for independent sterile operation in single colony inoculation culture and detection processes of the ketogulonigenium vulgare is met, so that the purpose of rapid, convenient and accurate high-throughput screening is achieved.