CN-122004124-A - Breeding method and application of spaceflight carried rice mutant strain Yunnan Tun 502 avionics M6-8

CN122004124ACN 122004124 ACN122004124 ACN 122004124ACN-122004124-A

Abstract

The invention discloses a breeding method and application of a space-borne rice mutant strain Yunnan Tun 502 avionics M6-8, and relates to the technical field of rice breeding, and the technical key points are that the method takes a conventional fragrant soft rice 'Yunnan Tun 502' stock seed with 8.2% of amylose as a material, and obtains SP 0 generation seeds through space-borne space mutagenesis; selecting excellent mutant strain with soft rice character, fragrance, precocity, strong tillering and rice blast resistance by combining ground multi-generation system breeding, phenotype screening and STR molecular marker identification, and finally selecting fragrant soft rice mutant strain 'Dianchun 502 avionics M6-8' with excellent comprehensive character by multi-point quality comparison test. The mutant strain has the advantages of keeping the taste quality of fragrant and soft rice, improving the yield by more than 8.1%, obviously enhancing the resistance to rice blast, shortening the growth period, realizing the synergistic improvement of fragrance, softness, early stage, rich stage and resistance, and being used as a new variety to be directly popularized or used as a high-quality parent for cross breeding.

Inventors

SU ZHENXI
SI SHIQUAN
CHEN YUMIN
YUAN PINGRONG
XIAO JUNQING
LIU WEIHUA
WU ZHIGANG
JIANG CHENG
GU QIONGYAO
GUO YONGMEI

Assignees

云南省农业科学院粮食作物研究所

Dates

Publication Date: 20260512
Application Date: 20260319

Claims (10)

1. A breeding method and application of a space-borne rice mutant strain Yunnan Tun 502 avionics M6-8 are characterized by comprising the following steps: Step 1, selecting original seeds of conventional fragrant soft rice 'Yunnan Tun 502' with the amylose content of 8.2%, subpackaging, then entering space along with a manned airship, staying on orbit for 6 months, and returning to the ground to obtain SP 0 generation seeds; Step 2, adopting single transplanting and equal quantity mixed harvesting of single main spikes in the generation of SP1, constructing mutant groups in the generation of SP2, screening out excellent single plants which are early maturing, strong tillering and rice blast resistance and have soft rice characters and fragrance, and screening out strains with stable agronomic characters and consistent fragrance in the generation of SP3-SP5 through low-heat river valley additive generation propagation; Extracting genome DNA of young leaves of 12 excellent strains of SP 5 generation, carrying out PCR amplification by adopting a FAM fluorescence modified RM85 primer, and screening a genetic difference strain with a RM85 locus showing a double-peak characteristic of 78bp and 93bp by capillary electrophoresis and software analysis; and 4, setting test points in different low, medium and high elevation areas of the indica rice area, carrying out a product ratio test through random block design, and determining and selecting to obtain the comprehensive excellent fragrant and soft rice mutant strain Yunnan Tun 502 avionics M6-8 by combining yield, resistance and rice quality indexes.
2. The breeding method according to claim 1, wherein the "yunnan 502" stock seeds in step 1) are required to satisfy the degradation characteristics of loss of rice blast resistance and reduction of yield potential, and the seeds are hermetically stored in a special biological sample bag throughout the carrying process.
3. The method for selectively breeding rice according to claim 1, wherein the specific standard for identifying the characteristics of the soft rice of the SP 2 generation in the step 2) is that the whole endosperm of the brown rice is in a milky, cloudy and turbid state and is in a non-transparent or semitransparent state, and the characteristics are not separated in offspring after being screened.
4. The breeding method according to claim 1, wherein the specific mode of the SP 3 -SP 5 generation added propagation in the step 2) is that the SP 3 generation is sowed in Yuanjiang, the SP 4 generation is compared with the strain developed in Lufeng city, the SP 5 generation is amplified and propagated in Yuanjiang in 2024 winter, and each generation adopts a single-root planting mode and conventional fertilizer and water management.
5. The method according to claim 1, wherein the PCR amplification system in the step 3) is 17. Mu.l of the Prime gold plate Mix, 1. Mu.l of 10. Mu. M PrimerF, 1. Mu.l of 10. Mu. M PrimerR, 1. Mu.l of the gDNA template, 20. Mu.l of the total system, and the amplification procedure is 98 ℃ pre-denaturation for 2min,35 cycles, 72 ℃ extension for 5min, and 4 ℃ storage.
6. The method according to claim 1, wherein the pretreatment of capillary electrophoresis in step 3) comprises mixing ABI HiDi Formamide with GeneScan 500LIZ internal standard at 130:1 to prepare mix, adding 10 μl mix and 0.5 μl sample template into each 96-well reaction well, centrifuging at 4000rpm, pre-denaturing at 95 ℃ for 5min, immediately cooling at-20 ℃, thawing, mixing, and detecting by ABI 3730xl genetic analyzer.
7. The method according to claim 1, wherein the excellent mutant strain selected in step 4) is selected to meet the following criteria of 8.5% amylose content, grade no more than 3% rice blast resistance, 139 days in growth period, 33.9g thousand kernel weight.
8. A method for high-yield cultivation of a soft-fragrant rice mutant obtained by breeding according to any one of claims 1 to 7, comprising the steps of: Seed treatment, namely selecting 'Yunnan Tun 502 avim 6-8' seeds, sun-drying the seeds for 2 days before seed soaking, and soaking the seeds for 36 hours by 'applying Baozhen'; Seedling raising and transplanting, namely, seedling age is controlled to be 30-35 days, strong seedlings are cultivated, and seedling is transplanted with tillers and medicines, 5-8 kg of urea is applied per mu 5 days before transplanting, and disease and pest control is synchronously carried out; Density control, namely adopting 4 inch multiplied by 8 inch transplanting density to ensure that the basic seedlings are about 4.0 ten thousand plants/mu; The water and fertilizer management adopts the modes of shallow water seedling planting, cun water turning, thin water tillering, seedling sunning, cun water spike promotion and seed wetting; and (3) pest control, namely, comprehensively controlling the rice blast and other pests and diseases in a targeted manner, and guaranteeing the robust growth of plants.
9. An application of a fragrant and soft rice mutant strain obtained by breeding according to any one of the methods of claims 1-7, characterized in that a 'yunnan 502 avim 6-8' mutant strain with a preservation number of CCTCC No. P202602 is used as a new variety of fragrant and soft rice, is popularized and planted in a Yunnan indica rice area, has both the characteristic of soft rice endosperm turbidity and natural fragrance, and is remarkably superior to an original variety 'yunnan 502' in high yield, disease resistance and adaptability.
10. An application of the fragrant and soft rice mutant strain obtained by breeding according to any one of the methods of claims 1-7, characterized in that the 'yunnan 502 avine 6-8' mutant strain is used as a breeding core parent, and is hybridized or backcrossed with rice varieties with bacterial blight resistance, rice planthopper resistance or high yield potential, and new varieties are cultivated by polymerizing excellent genes.

Description

Breeding method and application of spaceflight carried rice mutant strain Yunnan Tun 502 avionics M6-8 Technical Field The invention relates to the technical field of rice breeding, in particular to a breeding method and application of a space-borne rice mutant strain Yunnan Tun 502 avionics M6-8. Background The fragrant and soft rice is taken as an important product of high-end grains in China, and is favored by the market in terms of the flavor, softness, elasticity and smoothness. The Yunnan is used as the genetic diversity center of the origin of the soft rice and the rice seeds, has rich local soft rice resources, has low amylose content and is not regenerated after cooling, and is a precious gene library for breeding high-quality rice. However, the traditional fragrant soft rice has long faced the industry dilemma of 'high quality and low yield, high yield and low quality', and is characterized by more than 20% lower yield than hybrid rice, poor disease resistance, easy lodging and narrow adaptability. Taking Yunnan main cultivated variety 'Yunnan Tun 502' as an example, serious degeneration occurs in recent thirty years, the incidence rate of rice blast can reach 100%, the yield is reduced by more than 40%, the quality and the resistance are obviously reduced, and the industry is urgently required to cultivate a breakthrough new variety with both high quality and high yield characteristics. In order to solve the problems, the space mutation breeding technology becomes an important break. The technology induces the crop genome to generate heritable variation by utilizing the factors of microgravity, high-energy particle radiation and the like which are special in space environment, has the advantages of high mutation frequency, wide variation type, short breeding period and the like, and is suitable for quickly creating new germplasm. Based on the technical path, the invention selects the Yunnan Tun 502 seed to carry Shenzhou thirteen manned spacecraft to carry out space mutagenesis, and aims to create a new rice germplasm which can remarkably improve the yield, the resistance and the adaptability while keeping the good quality of the fragrant and soft rice in a mode of combining space mutagenesis with ground multi-generation breeding. Through systematic breeding, the invention successfully obtains a mutant strain 'Yunnan Tun 502 avionics M6-8', and the strain has the characteristics of precocity, strong tillering, large grains, high fruiting rate, 8.1 percent higher yield than the original strain and obviously improved resistance while retaining the turbidity characteristic and fragrance of soft rice endosperm. Genetic analysis proves that the gene has a difference from the original strain at the RM85 locus marked by STR, and belongs to a new material with definite genetic background. The mutant strain not only provides core germplasm for the update and rejuvenation of soft rice varieties, but also can be used as a key parent for high-quality and high-yield breeding of fragrant soft rice due to the high thousand seed weight characteristic. Disclosure of Invention The invention aims to solve the problems, and solves the problems of uncoordinated quality and yield, insufficient stress resistance, variety degradation, low breeding efficiency and the like in the prior art fragrant and soft rice industry for a long time by breeding excellent mutant new materials through spaceflight carrying. In order to achieve the purpose, the technical scheme of the invention is as follows, a breeding method and application of 502 avionics M6-8 of a space carrying rice mutant strain, comprising the following steps: Step 1, selecting original seeds of conventional fragrant soft rice 'Yunnan Tun 502' with the amylose content of 8.2%, subpackaging, then entering space along with a manned airship, staying on orbit for 6 months, and returning to the ground to obtain SP 0 generation seeds; Step 2, adopting single transplanting and equal quantity mixed harvesting of single main spikes in SP 1 generation, constructing mutant group in SP 2 generation, screening out excellent single plant which is early maturing, strong tillering, rice blast resistance and soft rice character and fragrance, and screening out plant line with stable agronomic character and consistent fragrance in SP 3-SP5 generation through low-heat valley generation propagation; Extracting genome DNA of young leaves of 12 excellent strains of SP 5 generation, carrying out PCR amplification by adopting a FAM fluorescence modified RM85 primer, and screening a genetic difference strain with a RM85 locus showing a double-peak characteristic of 78bp and 93bp by capillary electrophoresis and software analysis; and 4, setting test points in different low, medium and high elevation areas of the indica rice area, carrying out a product ratio test through random block design, and determining and selecting to obtain the comprehensive excellent fragrant and soft rice mutant s