Breeding method of high-oil rape germplasm

Abstract

The invention belongs to the technical field of rape breeding, and particularly relates to a breeding method of high-oil rape germplasm, the high-oil rape germplasm is obtained by breeding rape parents after physical mutagenesis and chemical mutagenesis treatment, chemical mutagenesis uses a chemical mutagenic agent prepared from EMS, MNU and NU7026, physical mutagenesis adopts low-energy nitrogen ion beams or gamma rays, and chemical mutagenesis adopts low-energy nitrogen ion beams or gamma rays. By utilizing a compound mutagenesis method, the stability of gene mutation is improved, the heritable variation spectrum is greatly widened, the time required from mutagenesis to obtaining of new materials with stable characters is shortened, and the purpose of rapid breeding of high-oil rape germplasm is achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oilseed rape breeding, and particularly relates to a breeding method of high-oil oilseed rape germplasm. BACKGROUND

[0002] In the field of breeding oilseed rape germplasm, the traditional and mainstream technical path relies on hybridization and phenotype screening. By selecting parents with different excellent traits for hybridization, in the offspring segregation population, the single plant gene phenotype or related morphological and physiological indexes are continuously screened for multiple generations to aggregate excellent alleles, so as to finally obtain new varieties with disease resistance, drought resistance, high oil and other traits. Although this traditional method has achieved remarkable results and has clear goals, its essence depends on the genetic variation carried by the parents themselves. If the diversity of alleles in the existing germplasm resource library is limited or has been fully explored, the potential for further breakthrough in oil content through hybrid recombination will face a bottleneck, that is, there is an improvement bottleneck. Secondly, drought resistance, high oil and other traits, as quantitative traits controlled by multiple genes and easily affected by the environment, show continuous variation in the hybrid offspring. There is often complex genetic linkage or negative correlation between single plant yield, resistance, maturity and other important agronomic traits, making it extremely slow and inefficient to break this unfavorable linkage and achieve multi-trait coordinated improvement through phenotype selection. In addition, from hybridization to obtaining new lines with stable traits, it usually takes a long process of multiple generations of selfing and selection, with long breeding cycle and high cost of land and labor. Therefore, although hybridization breeding is still the foundation, relying only on its own mechanism, in the rapid and breakthrough improvement of complex traits such as high oil, it has faced systematic challenges such as narrow genetic basis, limited selection efficiency and long breeding cycle, and urgently needs a more efficient and more targeted breeding method to cultivate new germplasm with outstanding traits. SUMMARY

[0003] In view of the above problems, the application provides a breeding method of high-oil oilseed rape germplasm, which initiates DNA double-strand breaks in oilseed rape genes as primary damage through physical mutagenesis, and then uses chemical mutagen to maintain the stability of the mutant genes, so as to greatly broaden the genetic variation spectrum, and finally screen new oilseed rape germplasm with significantly improved oil content.

[0004] To achieve the above purpose, the technical scheme adopted by the application is as follows: The application provides a breeding method of high-oil oilseed rape germplasm, which is obtained by mutagenesis breeding of oilseed rape parents, and specifically includes the following steps: Step 1: taking dry seeds of the oilseed rape parent for physical mutagenesis to obtain a physical mutagenesis variety; Step 2: chemically mutagenizing the physical mutagenesis variety to obtain high-oil oilseed rape germplasm.

[0005] Furthermore, the rapeseed parent line is selected from any one of Qinyou 10, Zhongshuang 11, and Fengyou 730.

[0006] Furthermore, the physical mutagenesis process uses a low-energy nitrogen ion beam or gamma rays.

[0007] Furthermore, the chemical mutagenesis process uses a chemical mutagen.

[0008] Furthermore, the chemical mutagen comprises the following raw materials: EMS (ethyl methanesulfonate), MNU (N-methyl-N-nitrosourea), NU7026 (DNA-PK inhibitor), and purified water, wherein the mass ratio of EMS, MNU, NU7026, and purified water is 0.4:0.2:0.15:100.

[0009] Furthermore, the steps of the physical mutagenesis are as follows: S1: Take the dry seeds of the rapeseed parent and divide them into 10 portions, each containing 200 seeds, and number them as Sample 1-10, for irradiation mutagenesis treatment. S2: Place samples 1-10 in a low-energy ion implanter or irradiation chamber, and apply a low-energy nitrogen ion beam or irradiation solution respectively. 60 Co-γ rays were used as the mutagen source. Different irradiation doses were set to uniformly irradiate the samples for 1 h. The seedlings of samples 1-10 after irradiation were investigated. Seeds of samples with a seedling rate of ≥50% were selected to obtain physically induced mutants.

[0010] Furthermore, the steps of the chemical mutagenesis are as follows: M1: The physically induced mutants obtained from the rapeseed parent lines were immersed in a chemical mutagen to ensure that all seeds were completely covered and not floating. They were then placed on a constant temperature shaker and shaken for 16 hours. The chemical mutagen interfered with the repair of DNA strand breaks caused by physical mutagenesis or maintained the status of germplasm mutant genes to obtain chemically induced mutants. M2: Rinse the chemically induced mutant thoroughly with running water to completely remove any residual reagents, thus obtaining the mutant; M3: The mutant species are cultivated, planted, and hybridized to stabilize the mutant traits and screen for high-oil rapeseed germplasm.

[0011] The beneficial effects achieved by this invention are as follows: This invention selects high-oil rapeseed germplasm by sequentially subjecting it to physical and chemical mutagenesis treatments. Utilizing their different mechanisms of action and timing, a breeding mechanism is constructed that extends from primary DNA damage to maintaining gene mutation traits. Low-energy nitrogen ion beams or gamma rays can induce high-density, relatively concentrated DNA double-strand breaks and other primary damage in the plant genome, laying the structural foundation for subsequent mutations. The subsequent application of a composite chemical mutagen, including a DNA-PK inhibitor, specifically interferes with the key pathways for high-fidelity repair of these breaks. This forces a large number of initial damages to be processed through error-prone backup repair mechanisms, significantly increasing the probability of diverse variations such as base substitutions, insertions, or deletions near the damage sites. Furthermore, mutations tend to be stably maintained in specific regions of the genome rather than being completely randomized. In addition, EMS and MNU, as alkylating agents, increase the overall load and complexity of the cellular repair system by creating complementary types of base damage. This synergistic effect essentially amplifies the mutagenic effect, greatly enriching the genetic diversity of the mutant library within an acceptable range of physiological damage. In particular, it increases the likelihood of beneficial mutations in gene networks related to lipid synthesis and accumulation, providing a richer pool of material for screening. Simultaneously, this breeding method achieves rapid reshaping of the genetic background through a one-step combined treatment, shortening the time required from mutagenesis to obtaining new materials with stable traits. While improving mutagenesis efficiency and directionality, it also ensures the safety and controllability of practical operations, providing a practical and feasible technical solution for the efficient and stable breeding of breakthrough high-oil rapeseed germplasm. Attached Figure Description

[0012] Figure 1 The results of the investigation on the seedling growth traits of rapeseed germplasm selected in Examples 2-5; Figure 2 The results of the thousand-grain weight and oil content determination of rapeseed germplasm selected in Examples 2-5 are as follows; Figure 3 The percentage of each fatty acid in the rapeseed germplasm selected in Examples 2-5; Figure 4 This is a volcano diagram of the differential genes in rapeseed germplasm selected in Example 3. Detailed Implementation

[0013] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0014] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0015] In the following embodiments, the breeding method for clubroot-resistant rapeseed varieties is as follows: Figure 1 As shown; in the following embodiments, unless otherwise specified, all methods are conventional; in the following embodiments, unless otherwise specified, all raw materials used are new materials purchased from the market.

[0016] Example 1: This example provides a chemical mutagen, comprising the following raw materials in parts by weight: 4 parts EMS, 2 parts MNU, 1.5 parts NU7026, and 1000 parts purified water; The chemical mutagen is prepared as follows: 1.5 parts of NU7026 are dispersed in 100 parts of purified water, heated at 60°C, vortexed, and sonicated to dissolve, thus obtaining a NU7026 solution. 4 parts of EMS and 2 parts of MNU are dissolved in 400 parts of purified water under light protection and stirring to obtain solution A. Solution A and the NU7026 solution are mixed, and then 500 parts of purified water are added. The mixture is stirred and mixed under light protection to obtain the chemical mutagen. It should be prepared and used immediately and stored in a brown bottle.

[0017] Example 2: This invention provides a method for breeding high-oil rapeseed germplasm, which is obtained by selecting Qinyou 10 after physical mutagenesis and chemical mutagenesis treatment.

[0018] The physical mutagenesis treatment method is as follows: S1: Take the dry seeds of Qinyou No. 10 and divide them into 10 portions, each containing 200 seeds. Place them into breathable sterile seed bags and number them as sample 1-10. After dispensing, place all samples in a constant temperature drying oven and balance the moisture at 40℃ for 48 hours to stabilize the seed moisture content at around 10% to ensure the consistency of subsequent irradiation treatment. S2: Place the samples 1-10 above on the sample stage of the low-energy ion implanter, use a low-energy nitrogen ion beam as the mutagenesis source, and set the ion energy to 25 keV and the beam current density to 15 μA / cm². 2 The vacuum level is maintained at 5.0 × 10⁻⁶. -3 Pa, setting up irradiation dose gradients: Samples 1-10 received 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, and 10.0 (×10) irradiation doses respectively. 16 ions / cm 2The sample stage was uniformly irradiated with a dose of 100 mg / dose at room temperature for 1 hour. During the irradiation process, the sample stage was rotated at a constant speed to ensure the uniformity of the dose distribution and to obtain the irradiated seed. S3: Take 50 seeds from each of the irradiated samples 1-10 and conduct a preliminary seedling rate test on a standard germination bed. This serves as a rapid quality control indicator for assessing physiological damage and determining the applicable group for subsequent chemical treatment. Select the seeds corresponding to the samples with a seedling rate ≥50% after irradiation, namely samples 1-3, 6, 8, and 9, with seedling rates of 64%, 80%, 74%, 58%, 76%, and 86%, respectively, as physical mutagenized varieties.

[0019] The chemical mutagenesis treatment method is as follows: M1: Samples 1-3, 6, 8 and 9 of the physical mutagenesis obtained by physical mutagenesis of Qinyou 10 were immersed in chemical mutagen to ensure that all seeds were completely covered and not floating. They were placed on a constant temperature shaker and shaken at 100 rpm for 16 h. The chemical mutagen interfered with the repair of DNA strand breakage caused by physical mutagenesis or maintained the status of germplasm mutant genes, thus obtaining chemical mutagenesis. M2: Rinse the chemically induced mutant seeds thoroughly with running water to completely remove any residual reagents. After rinsing, spread the seeds evenly on gauze, ventilate, and dry to obtain the mutant seeds. M3: 100 mutant seeds from each sample were taken and cultivated. The self-pollinated seeds of each plant were harvested to obtain M2 generation seeds. The M2 generation seeds were planted and cultivated to the M3 generation. The high-oil-content selected lines with stable and consistent traits in the M3 generation were crossbred with the rapeseed parent Qinyou 10. The new rapeseed germplasm sample 2 with high oil content, high yield, resistance and stable quality was obtained, namely high-oil rapeseed germplasm.

[0020] Example 3: This invention provides a method for breeding high-oil rapeseed germplasm, which is obtained by selecting Qinyou 10 after physical mutagenesis and chemical mutagenesis treatment.

[0021] The physical mutagenesis treatment method is as follows: S1: Take the dry seeds of Qinyou No. 10 and divide them into 10 portions, each containing 200 seeds. Place them into breathable sterile seed bags and number them as sample 1-10. After dispensing, place all samples in a constant temperature drying oven and balance the moisture at 40℃ for 48 hours to stabilize the seed moisture content at around 10% to ensure the consistency of subsequent irradiation treatment. S2: Place the above samples 1-10 in the irradiation chamber and use... 60Co-γ rays were used as the mutagenesis source, and different irradiation doses were set for uniform irradiation. The irradiation doses of samples 1-10 were 100, 200, 400, 600, 800, 1000, 1200, 1400, 1600, and 1800 Gy, respectively. The irradiation time for each dose was 1 hour at room temperature. During the irradiation process, the sample stage was kept rotating at a constant speed to ensure the uniformity of the dose distribution and to obtain the irradiated species. S3: Take 50 seeds from each of the irradiated samples 1-10 and conduct a preliminary seedling rate test on a standard germination bed. Select the seeds corresponding to the samples with a seedling rate ≥50% after irradiation as samples 3-5 and 7, with seedling rates of 84%, 80%, 94%, and 84%, respectively, as physical mutagenesis varieties.

[0022] The chemical mutagenesis treatment method is as follows: M1: Samples 3-5 and 7 of the physical mutants obtained by physical mutagenesis of Qinyou 10 were immersed in chemical mutagen to ensure that all seeds were completely covered and not floating. They were placed on a constant temperature shaker and shaken at 100 rpm for 16 h. The chemical mutagen interfered with the repair of DNA strand breakage damage caused by physical mutagenesis or maintained the status of germplasm mutant genes, thus obtaining chemical mutants. M2: Rinse the chemically induced mutant seeds thoroughly with running water to completely remove any residual reagents. After rinsing, spread the seeds evenly on gauze, ventilate, and dry to obtain the mutant seeds. M3: 100 mutant seeds from each sample were taken and cultivated. The self-pollinated seeds of each plant were harvested to obtain M2 generation seeds. The M2 generation seeds were planted and cultivated to the M3 generation. The high-oil-content selected lines with stable and consistent traits in the M3 generation were hybridized with the rapeseed parent Qinyou 10. Seven new rapeseed germplasm samples with high oil content, high yield, resistance and stable quality were obtained, namely high-oil rapeseed germplasm.

[0023] Example 4: This invention provides a method for breeding high-oil rapeseed germplasm, which is obtained by selecting Zhongshuang 11 after physical and chemical mutagenesis treatment.

[0024] The physical mutagenesis treatment method is as follows: S1: Take the dry seeds of Zhongshuang No. 11 and divide them into 10 portions, 200 seeds in each portion. Place them into breathable sterile seed bags and number them as sample 1-10. After dispensing, place all samples in a constant temperature drying oven and balance the moisture at 40℃ for 48 hours to stabilize the seed moisture content at 10% to ensure the consistency of subsequent irradiation treatment. S2: Place the above samples 1-10 in the irradiation chamber and use... 60Co-γ rays were used as the mutagenesis source, and different irradiation doses were set for uniform irradiation. The irradiation doses of samples 1-10 were 100, 200, 400, 600, 800, 1000, 1200, 1400, 1600, and 1800 Gy, respectively. The irradiation time for each dose was 1 hour at room temperature. During the irradiation process, the sample stage was kept rotating at a constant speed to ensure the uniformity of the dose distribution and to obtain the irradiated species. S3: Take 50 seeds from each of the irradiated samples 1-10 and conduct a preliminary seedling rate test on a standard germination bed. Select the seeds corresponding to the samples with a seedling rate ≥50% after irradiation as samples 2 and 4-7, with seedling rates of 72%, 86%, 92%, 86%, and 78%, respectively, as physical mutagenesis varieties.

[0025] The chemical mutagenesis treatment method is as follows: M1: Samples 2 and 4-7, obtained by physical mutagenesis of Zhongshuang 11, were immersed in chemical mutagen to ensure that all seeds were completely covered and not floating. They were placed on a constant temperature shaker and shaken at 100 rpm for 16 h. Chemical mutagen was used to interfere with the repair of DNA strand breaks caused by physical mutagenesis or to maintain the status of germplasm mutant genes, thus obtaining chemical mutagenized varieties. M2: Rinse the chemically induced mutant seeds thoroughly with running water to completely remove any residual reagents. After rinsing, spread the seeds evenly on gauze, ventilate, and dry to obtain the mutant seeds. M3: 100 mutant seeds from each sample were taken and cultivated. The self-pollinated seeds of each plant were harvested to obtain M2 generation seeds. The M2 generation seeds were planted and cultivated to the M3 generation. The high-oil-content selected lines with stable and consistent traits in the M3 generation were crossbred with the rapeseed parent Shuang 11. The resulting new rapeseed germplasm sample 4, which has high oil content, high yield, resistance and stable quality, was obtained.

[0026] Example 5: This invention provides a method for breeding high-oil rapeseed germplasm, which is obtained by selecting high-oil rapeseed germplasm from Fengyou 730 after physical mutagenesis and chemical mutagenesis treatment.

[0027] The physical mutagenesis treatment method is as follows: S1: Take the dry seeds of Fengyou 730 and divide them into 10 portions, 200 seeds in each portion. Place them into breathable sterile seed bags and number them as sample 1-10. After dispensing, place all samples in a constant temperature drying oven and balance the moisture at 40℃ for 48 hours to stabilize the seed moisture content at 10% to ensure the consistency of subsequent irradiation treatment. S2: Place the above samples 1-10 in the irradiation chamber and use... 60Co-γ rays were used as the mutagenesis source, and different irradiation doses were set for uniform irradiation. The irradiation doses of samples 1-10 were 100, 200, 400, 600, 800, 1000, 1200, 1400, 1600, and 1800 Gy, respectively. The irradiation time for each dose was 1 hour at room temperature. During the irradiation process, the sample stage was kept rotating at a constant speed to ensure the uniformity of the dose distribution and to obtain the irradiated species. S3: Take 50 seeds from each of the irradiated samples 1-10 and conduct a preliminary seedling rate test on a standard germination bed. Select the seeds corresponding to the samples with a seedling rate ≥50% after irradiation as samples 5-9, with seedling rates of 66%, 86%, 84%, 80%, and 70% respectively, as physical mutagenesis varieties.

[0028] The chemical mutagenesis treatment method is as follows: M1: The physical mutagen samples 5-9 obtained by physical mutagenesis of Fengyou 730 were immersed in chemical mutagen to ensure that all seeds were completely covered and not floating. They were placed on a constant temperature shaker and shaken at 100 rpm for 16 h. The chemical mutagen interfered with the repair of DNA strand breakage damage caused by physical mutagenesis or maintained the status of germplasm mutation genes, thus obtaining chemical mutagen. M2: Rinse the chemically induced mutant seeds thoroughly with running water to completely remove any residual reagents. After rinsing, spread the seeds evenly on gauze, ventilate, and dry to obtain the mutant seeds. M3: 100 mutant seeds from each sample were taken and cultivated. The self-pollinated seeds of each plant were harvested to obtain M2 generation seeds. The M2 generation seeds were planted and cultivated to the M3 generation. The high-oil-content selected lines with stable and consistent traits in the M3 generation were crossbred with the rapeseed parent Fengyou 730. Eight new rapeseed germplasm samples with high oil content, high yield, resistance and stable quality were obtained, namely high-oil rapeseed germplasm.

[0029] Variation rate investigation: Phenotypic variation plants were investigated and the variation rate was calculated for the high-oil rapeseed germplasm cultivated in Examples 2-5 throughout its entire growth period. Corresponding varieties without mutagenesis culture were used as the control group. Cotyledon was recorded at the bud stage, true leaf at the seedling stage, main stem and branch angle at the bolting stage, and flowering at the flowering stage. Variation types were divided into cotyledon variation, true leaf variation, stem variation, flowering variation, and flower variation. The oil content variation frequency and variation rate of each variation type were calculated for each sample. At the same time, the variation heritability of the M3 generation was calculated. Variation frequency (%) = number of variant plants / total number of plants × 100%, variation rate (%) = number of variant plants of the same type / total number of plants of the same line × 100%, variation heritability (%) = coefficient of plants with variant traits / coefficient of total plants × 100%. The results of variation frequency and variation heritability are shown in Table 1, and the results of variation rate of each type are shown in Table 2.

[0030] Seedling growth observation: High-oil rapeseed germplasm selected in Examples 2-5 was used, and its seedling growth was recorded and photographed after cultivation. The corresponding rapeseed parents were used as controls. The results are shown in the table below. Figure 1 .

[0031] Oil content assessment: High-oil rapeseed germplasm selected in Examples 2-5 was used. After cultivation, rapeseed was harvested, and its yield was assessed. Near-infrared reflectance spectroscopy was used to determine its oil content. Gas chromatography was used to determine the content of oleic acid, linoleic acid, linolenic acid, palmitic acid, and stearic acid in the rapeseed. The results of thousand-grain weight and oil content are shown below. Figure 2 The results for the content of each fatty acid are shown in the figure. Figure 3 .

[0032] Transcriptome sequencing: Differentially expressed genes were screened from high-oil rapeseed germplasm selected in Examples 2-5. Normal, unmutated corresponding rapeseed parents were used as the control group. Gene sequencing was performed, and differentially expressed genes were analyzed and statistically analyzed. The results are shown in Table 3. The differential gene volcano diagram of Example 3 is shown below. Figure 4 .

[0033] Table 1. Frequency and Heritability of Oil Variation

[0034] Table 2 Variation Rates by Type

[0035] Table 3 Differential Gene Analysis

[0036] The results in Tables 1 and 2 show that after physical and chemical mutagenesis treatment, the samples all exhibited varying degrees of variation. Among them, the oil content variation frequency of Example 3 was relatively high and the genetic traits were relatively stable. In addition, the growth traits of rapeseed plants also showed a certain degree of variation. Under the same mutagenesis treatment, the mutagenesis sensitivity of the three parents from strong to weak was Qinyou 10 > Fengyou 730 > Zhongshuang 11.

[0037] Figure 1 The results showed that after physical and chemical mutagenesis treatment, the seedling growth of each rapeseed variety changed to some extent, with differences in plant height, leaf width, and stem size.

[0038] Figure 2 and Figure 3 The results showed that the rapeseed germplasm bred by mutation in Example 5 had the largest thousand-grain weight, and the rapeseed germplasm sample 7 bred in Example 3 had the highest oil content, nearly 80%, and the highest proportion of oleic acid.

[0039] Table 3 and Figure 4The results showed that there were a large number of differentially expressed genes between the rapeseed germplasm bred after mutagenesis and the parents. These differences in genes were the main reason for the changes in traits and oil content. Among them, Example 5 had the most differentially expressed genes.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0041] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention. The actual application is not limited to this. In conclusion, if those skilled in the art are inspired by this description and design similar methods and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A method for breeding high-oil rapeseed germplasm, characterized in that, The high-oil rapeseed germplasm was obtained from rapeseed parents through mutagenesis and selection, specifically including the following steps: Step 1: Take dry seeds of the rapeseed parent and perform physical mutagenesis to obtain physically induced mutants; Step 2: Chemical mutagenesis was carried out on the physically induced mutants to select and breed high-oil rapeseed germplasm; The chemical mutagenesis process uses a chemical mutagen; The chemical mutagen comprises the following raw materials: ethyl methanesulfonate, N-methyl-N-nitrosourea, NU7026, and purified water; In step 1, the specific steps of the physical mutagenesis are as follows: S1: Take the dry seeds of the rapeseed parent, package and number them to obtain samples; S2: Irradiate the samples and select seeds with a seedling survival rate of ≥50% to obtain physically induced mutants.

2. The method for breeding high-oil rapeseed germplasm according to claim 1, characterized in that, The specific steps of the chemical mutagenesis are as follows: M1: The physical mutagen was immersed in a chemical mutagen and subjected to shaking treatment to obtain the chemical mutagen; M2: Clean the chemically induced mutant to obtain the mutant; M3: The induced mutants are cultivated, planted, and hybridized to obtain high-oil rapeseed germplasm.

3. The method for breeding high-oil rapeseed germplasm according to claim 1, characterized in that, The rapeseed parent line is selected from any one of Qinyou 10, Zhongshuang 11 and Fengyou 730.

4. The method for breeding high-oil rapeseed germplasm according to claim 1, characterized in that, In step 1, the physical mutagenesis process uses a low-energy nitrogen ion beam or gamma rays.

5. The method for breeding high-oil rapeseed germplasm according to claim 1, characterized in that, The mass ratio of ethyl methanesulfonate, N-methyl-N-nitrosourea, NU7026 and purified water is 0.4:0.2:0.15:100.

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