Methods for selecting and breeding water-saving, high-quality and multi-resistant winter wheat

Abstract

A method for selecting and breeding water-saving, high-quality, and multi-resistant winter wheat with improved protein quality, cold resistance, drought resistance, water conservation, and pest and disease resistance comprises the following steps: first, selecting parents; second, planting and hybridizing to obtain the F0 generation; third, backcrossing the F0 generation with high-quality wheat to obtain the backcross F0 generation; fourth, planting the backcross F0 again to obtain the F1 generation; fifth, screening high-quality marker wheat varieties; and sixth, identifying water-saving performance under different water conditions, selecting strains with good water-saving performance, and simultaneously conducting resistance identification on key materials.

Description

Technical Field

[0001] The invention belongs to the technical field of wheat progeny selection and breeding methods, and in particular relates to a winter wheat progeny selection and breeding method. Background Art

[0002] In the winter wheat breeding process, varieties with required performance are obtained by hybridizing parents. Due to the characteristics of winter wheat requiring vernalization and tillering, current breeding has the following defects: First, one generation per year is generally adopted during breeding, and the breeding cycle is long, which is not conducive to the promotion of new wheat varieties; Second, when selecting winter wheat water-saving and high-quality varieties, parents use high-quality wheat varieties and water-saving wheat hybrids to obtain F0 generations, and then directly carry out F1 generation to high-generation breeding, which results in poor stability of wheat quality; Third, when each generation of breeding is compared with high quality and water-saving performance, the experimental steps are cumbersome and the experimental workload is large. To solve the above technical problems, CN110313397B proposes a method for selecting and breeding water-saving and high-quality winter wheat. However, according to actual results, the wheat varieties selected by this method still have a lot of room for improvement in terms of protein quality, cold resistance, drought resistance and water-saving performance, disease and insect resistance, etc. Therefore, it is very necessary to improve the above method to obtain further improvement in terms of protein quality, cold resistance, drought resistance and water-saving performance, disease and insect resistance, etc. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method for selecting and breeding water-saving, high-quality and multi-resistant winter wheat with further improved protein quality, cold resistance, drought resistance and water-saving performance, and disease and insect resistance.

[0004] In order to solve the above problems, the technical solution adopted by the method for selecting and breeding water-saving, high-quality and multi-resistant winter wheat of the present invention is as follows:

[0005] The method comprises the following steps:

[0006] Step 1: Choose the parents

[0007] Water-saving and high-yield wheat materials and high-quality wheat materials with molecular markers of glutenin 5+10, 7+8, 17+18 subunits and secalin deficiency were selected as parents;

[0008] The second step is to plant and hybridize to obtain F0 generation

[0009] During the normal winter wheat planting season, the selected parents are planted in an area suitable for planting winter wheat, and then the two parents are hybridized, and the harvested wheat is used as the F0 generation;

[0010] The third step is to backcross the F0 generation with high-quality wheat to obtain the backcross F0 generation.

[0011] During the normal winter wheat planting season, the F0 generation and high-quality wheat parents are planted in the field. The F0 generation wheat is tested for molecular markers of glutenin 5+10, 7+8, 17+18 subunits and secalin deficiency. Wheat containing the relevant markers is used as the female parent and backcrossed with the high-quality parents. After maturity, backcross F0 generation seeds are obtained.

[0012] The fourth step is to backcross the F0 and plant it again to get the F1 generation.

[0013] Backcross F0 generation wheat was planted in the field and harvested to obtain the F1 generation. Before harvest, glutenin 5+10, 7+8, 17+18 subunits and secalin deficiency molecular markers were detected, and wheat containing glutenin high-quality subunits and secalin deficiency molecular markers was used as the F1 generation.

[0014] Step 5: Screening high-quality marked wheat varieties

[0015] (1) In the early F2 generation, heterosis of the combinations was observed and molecular markers of glutelin 5+10, 7+8, 17+18 subunits and secalin deficiency were detected;

[0016] (2) In the early F3 generation, single plants were selected and the molecular markers of glutenin high-quality subunits and secalin deficiency were tested on the selected single plants. 40-50g of seeds were sampled from the lines with molecular markers to determine the gluten index, and the materials with a gluten index of more than 90% were selected.

[0017] (3) For the early F4 generation, select individual plants and excellent strains, using Heng 4399, Jimai 22, and Heshiluan 02-1 as controls, and focus on selecting individual plants with strong tillering ability, number of grains per ear ≥40, 1,000-grain weight ≥40g, full grains, good cold resistance, and good plant type. Continue to test for molecular markers of glutenin high-quality subunits and secalin deficiency. Select 40-50g seeds of key strains to test the gluten index, and screen materials with a gluten index of more than 90%. For materials that meet the standards, select 120 seeds, divide them into three portions, 40 seeds each, and select three locations within Baoding City for cold resistance screening;

[0018] (IV) For the F5-F7 generations, select individual plants and excellent strains, using Heng 4399, Jimai 22 and Shiluan 02-1 as controls, and focus on selecting individual plants with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance and good plant shape, and continue to test for molecular markers of glutenin high-quality subunits and secalin deficiency; select 40-50g of seeds from all screened strains to test the gluten index, and screen materials with a gluten index of more than 90%. For the materials that meet the standards, select 120 seeds, divide them into three parts, 40 seeds in each part, and select three places in Baoding City for cold resistance screening.

[0019] The sixth step is to identify water-saving performance under different water conditions, select varieties with good water-saving performance, and conduct resistance identification on key materials.

[0020] (1) Identify the high yield and quality of the strains selected from the F4-F7 generations

[0021] Identification conditions: Three treatments (0 spring watering, 1 spring watering, and 2 spring watering) were set up without replication. Heng 4399, Jimai 22, and Shiluan 02-1 were used as controls to conduct water-saving and high-yield quality and stress resistance identification. The materials were evaluated for drought resistance, water-saving properties, and high yield. The quality stability of the materials and the molecular markers for the deletion of glutenin 5+10, 7+8, 17+18 subunits, and secalin were also tested.

[0022] Selection criteria for the Drought Resistance and Water-Saving Index: For drought resistance, select materials with yields exceeding the control under the 0-water treatment, using a 3% screening index. Materials achieving a 3% or higher yield were selected and the percentage value was directly calculated, i.e., an increase of x% in yield was labeled x. For water-saving, select materials with yields exceeding the control under the 1-water treatment, using a 3% screening index. Materials achieving a 3% or higher yield was selected and the percentage value was directly calculated, i.e., an increase of y% in yield was labeled y. The Water-Saving Index (WSI) was calculated based on the yield results under the 1-water and 2-water treatments, ultimately forming the Drought Resistance and Water-Saving Index selection index (DWUI) = x*y*WSI. Varieties with a DWUI value greater than 10 were selected. Furthermore, the following conditions must be met: TaRa-F, TaRa-R, TaRb-F, and TaRb-R molecular markers were tested after the F5 generation. Specifically, among varieties with a DWUI value greater than 10, those with these markers were selected.

[0023] High-yield identification: Using Heng 4399 and Jimai 22 as controls, focus on selecting individual plants or strains with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance, and good plant shape;

[0024] Quality stability identification: Using Shiluan 02-1 as a control, the gluten index was detected, and the gluten index > 90% was selected, and the molecular markers of gluten superior subunits and secalin deficiency were identified and tracked.

[0025] (2) Identify the cold resistance and disease and insect resistance of the strains selected from the F4-F7 generations

[0026] Conditions for cold resistance identification: Three locations were selected in Baoding City, a wheat-growing area in the central and northern Hebei Province, for multi-point cold resistance identification, focusing on screening materials with good cold resistance. At the same time, vernalization gene testing was carried out to test the winter-spring characteristics of the varieties.

[0027] Cold resistance index CRI: The dead stem rate is used as a reference to form the cold resistance index. The specific formula is: the average value of the three sites (0.2 / dead stem rate of the test material). The cold resistance index test result is >=1.

[0028] Identification of disease and insect resistance: 150 seeds of each strain were selected and divided into three parts, with 50 seeds in each part, for identification of powdery mildew, stripe rust and leaf rust. Among the three diseases, the ones with one reaching medium resistance or above, or two reaching medium susceptibility or above can be selected. DETAILED DESCRIPTION

[0029] In order to solve the above problems, the technical solution adopted by the method for selecting and breeding water-saving, high-quality and multi-resistant winter wheat of the present invention is as follows:

[0030] The method comprises the following steps:

[0031] Step 1: Choose the parents

[0032] Water-saving and high-yield wheat materials and high-quality wheat materials with molecular markers of glutenin 5+10, 7+8, 17+18 subunits and secalin deficiency were selected as parents;

[0033] The second step is to plant and hybridize to obtain F0 generation

[0034] During the normal winter wheat planting season, the selected parents are planted in an area suitable for planting winter wheat, and then the two parents are hybridized, and the harvested wheat is used as the F0 generation;

[0035] The third step is to backcross the F0 generation with high-quality wheat to obtain the backcross F0 generation.

[0036] During the normal winter wheat planting season, F0 generation wheat and high-quality wheat parents were planted in the field. Molecular markers for the absence of glutenin subunits 5+10, 7+8, and 17+18, as well as secalin, were tested in the F0 generation wheat. Wheat containing the relevant markers was used as the maternal parent and backcrossed with the high-quality parent. After maturity, backcross F0 generation seeds were obtained. To improve gluten quality, this application not only tested glutenin 5+10, but also glutenin subunits 7+8 and 17+18, resulting in a significant improvement in protein quality.

[0037] The fourth step is to backcross the F0 and plant it again to get the F1 generation.

[0038] Backcross F0 generation wheat is planted in the field and harvested to obtain the F1 generation. Before harvest, the wheat is tested for molecular markers lacking glutenin subunits 5+10, 7+8, and 17+18, as well as secalin. Wheat containing molecular markers lacking high-quality glutenin subunits and secalin is selected as the F1 generation. To address the shortcomings of the original breeding procedure, the present application removes the germination step, simplifying the breeding process. By leveraging improvements to subsequent breeding steps, the final result is that the removal of the germination step does not lead to a decrease in breeding quality, but rather achieves technical results far exceeding the original breeding quality.

[0039] Step 5: Screening high-quality marked wheat varieties

[0040] (1) In the early F2 generation, observe the heterosis of the combination and detect the molecular markers of glutenin 5+10, 7+8, 17+18 subunits and secalin deficiency; F0-F2 generations can be carried out under the condition of increased generation to improve efficiency.

[0041] (2) In the early F3 generation, single plants were selected, and molecular markers of glutenin high-quality subunits and secalin deficiency were detected for the selected single plants. 40-50g of seeds were sampled from the lines with molecular markers to determine the gluten index, with a focus on screening materials with a gluten index of more than 90%. Compared with the original method of only testing 4-5 seeds, the 40-50g seed test in this application significantly improved the comprehensiveness and representativeness of the test. Moreover, compared with the original method of only testing IG content and pre-evaluating the gluten quality of the offspring, in order to improve the gluten quality, this application, after continuous experiments, finally determined that only materials with a gluten index of more than 90% were required. In this way, not only the step of detecting IG content was omitted, but also a technical effect that was significantly better than the original method was achieved.

[0042] (III) For the early F4 generation, select individual plants and excellent strains, with Heng 4399, Jimai 22 and Heshiluan 02-1 as controls, focus on selecting individual plants with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance and good plant type, continue to detect molecular markers of gluten subunits and secalin deficiency, select 40-50g seeds for key strains to detect gluten index, screen materials with gluten index above 90%, select 120 seeds for materials that meet the standards, divide them into three parts, 40 grains each, and select three places in Baoding for cold resistance screening; compared with the original method of only detecting IG content and pre-evaluating the gluten quality of offspring, this application is to improve the quality of flour. Gluten quality. After continuous experiments, it was finally determined that only materials with a gluten index of more than 90% need to be screened. In this way, not only the step of detecting IG content is omitted, but also a technical effect that is significantly better than the original method is achieved. At the same time, it was found in actual use that only using Heng 4399 as a control would result in unstable breeding results. After repeated research and comparison by the applicant, it was found that the problem lies in the reference Heng 4399. In order to overcome this defect, the applicant added Jimai 22. The combination of these two can solve the defect of using only Heng 4399 as a reference. At the same time, Heng 4399 can also supplement and balance Jimai 22, overcoming the defects brought by the single reference of Jimai 22.

[0043] (IV) For the F5-F7 generations, select individual plants and excellent strains, using Heng 4399, Jimai 22 and Shiluan 02-1 as controls, and focus on selecting individual plants with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance and good plant shape, and continue to test for molecular markers of glutenin high-quality subunits and secalin deficiency; select 40-50g of seeds from all screened strains to test the gluten index, and screen materials with a gluten index of more than 90%. For the materials that meet the standards, select 120 seeds, divide them into three parts, 40 seeds in each part, and select three places in Baoding City for cold resistance screening. Compared to the original method of testing only 4-5 seeds, the present application's 40-50g seed assay significantly improves the comprehensiveness and representativeness of the test. Furthermore, compared to the original method of only testing IG content and pre-assessing the gluten quality of future generations, the present application, through continuous experimentation, ultimately determined that it was sufficient to screen only materials with a gluten index of 90% or higher to improve gluten quality. This not only eliminates the step of testing IG content but also achieves technical results that are significantly superior to the original method. The reference variety Jimai 22 has been added. Combining these two varieties can address the drawbacks of using only Heng 4399 as a reference. Heng 4399 can also supplement and balance Jimai 22, overcoming the drawbacks of using only Jimai 22 as a reference.

[0044] The sixth step is to identify water-saving performance under different water conditions, select varieties with good water-saving performance, and conduct resistance identification on key materials.

[0045] (1) Identify the high yield and quality of the strains selected from the F4-F7 generations

[0046] Identification conditions: Three treatments (0 spring watering, 1 spring watering, and 2 spring watering) were set up without replication. Heng 4399, Jimai 22, and Shiluan 02-1 were used as controls to conduct water-saving and high-yield quality and stress resistance identification. The materials were evaluated for drought resistance, water-saving properties, and high yield. The quality stability of the materials and the molecular markers for the deletion of glutenin 5+10, 7+8, 17+18 subunits, and secalin were also tested.

[0047] Selection criteria for the Drought Resistance and Water-Saving Index: For drought resistance, select cultivars with yields exceeding the control under the 0-water treatment, using a 3% screening index. Materials achieving a 3% or higher yield were selected and the percentage value was calculated directly, i.e., an increase of x% in yield was labeled x. For water-saving, select cultivars with yields exceeding the control under the 1-water treatment, using a 3% screening index. Materials achieving a 3% or higher yield were selected and the percentage value was calculated directly, i.e., an increase of y% in yield was labeled y. The Water-Saving Index (WSI) was calculated based on the yield results for the 1-water and 2-water treatments (referring to DB13 / T2792-2018). The final selection criteria for the Drought Resistance and Water-Saving Index were DWUI = x*y*WSI. Varieties with a DWUI greater than 10 were selected. Furthermore, the following criteria must be met: TaRa-F, TaRa-R, TaRb-F, and TaRb-R molecular markers were tested after the F5 generation. Specifically, among cultivars with a DWUI greater than 10, those harboring these markers were selected. The drought resistance and water-saving selection index of this application takes into account three indicators as judgment criteria at the same time, breaking the shortcomings of the past evaluation of a single drought resistance index and a single water-saving index that cannot reflect the comprehensive drought resistance and water-saving characteristics of the variety. At the same time, it also overcomes the defect of the original separation of appearance judgment and gene judgment. For the first time, appearance judgment and gene judgment are combined and used to evaluate drought resistance and water-saving properties, comprehensively reflecting the drought resistance and water-saving performance of the variety, and providing selection indicators for the water-saving wheat industry to improve the comprehensive resistance of varieties. The calculation formula of the WSI water-saving index is WSI=Y a 4 *Y m -1 *Y M *(Y A 4 ) -1 , where Y a is the grain yield of the tested material under stress treatment (kg), Y m Grain yield of the tested material control treatment (kg), Y M is the grain yield of the control variety and the control treatment (kg), Y A is the grain yield (kg) of the control variety under stress treatment.

[0048] High-yield identification: Using Heng 4399 and Jimai 22 as controls, focus on selecting individual plants or strains with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance, and good plant shape;

[0049] Quality stability identification: Using Shiluan 02-1 as a control, the gluten index was detected, and the gluten index > 90% was selected, and the molecular markers of gluten superior subunits and secalin deficiency were identified and tracked.

[0050] (2) Identify the cold resistance and disease and insect resistance of the strains selected from the F4-F7 generations

[0051] Conditions for cold resistance identification: Three locations were selected in Baoding City, a wheat-growing area in the central and northern Hebei Province, for multi-point cold resistance identification, focusing on screening materials with good cold resistance. At the same time, vernalization gene testing was carried out to test the winter-spring characteristics of the varieties.

[0052] Cold resistance index CRI: The dead stem rate is an important reference to form the cold resistance index. The specific formula is: 0.2 / determined material dead stem rate (average value of three sites). If the cold resistance index test result is >= 1, materials with a value of 2.1 or above are preferred. Cold resistance index, targeting the areas in central and northern Hebei that are prone to frost damage, multiple sites are selected for cold resistance identification. The data from multiple sites are used to evaluate the comprehensive cold resistance of the varieties, providing an intuitive, concise and effective selection index. At the same time, combined with the molecular detection of vernalization genes, materials with good cold resistance index and excellent vernalization genes are selected as the key materials for wide adaptability breeding.

[0053] Identification of disease and pest resistance: 150 seeds were selected from each strain and divided into three parts, with 50 seeds in each part. With the help of the National Wheat Industry Technology System's Disease and Pest Resistance Identification Platform, professional identification of powdery mildew, stripe rust, and leaf rust was carried out. At the same time, combined with the results of natural field identification, excellent resistant materials were screened out.

[0054] Selection criteria for pest and disease resistance: Select resistance to powdery mildew, stripe rust, and leaf rust. Resistance levels are generally categorized into five levels: immune, highly resistant, moderately resistant, moderately susceptible, and highly susceptible. Materials with moderate resistance or higher to one of the three diseases, or moderately susceptible to two or more, are considered for selection. Of course, the better the resistance, the higher the value of the selection. Materials with high susceptibility to two or all three diseases are eliminated.

[0055] The subsequent adjustments to these steps are mainly proposed in response to the prior application. These steps are combined with the previous steps to form an overall breeding method. Compared with the prior application of the background technology, this method has significantly improved wheat breeding in terms of protein quality, cold resistance, drought resistance and water saving, and disease and insect resistance.

Claims

1. A method for selecting and breeding water-saving, high-quality, and multi-resistant winter wheat, comprising the following steps: The first step is to choose the parents: Water-saving and high-yield wheat materials and high-quality wheat materials with molecular markers of glutenin 5+10, 7+8, 17+18 subunits and secalin deletion were selected as parents; The second step is to plant and hybridize to obtain the F0 generation: During the normal winter wheat planting season, the selected parents are planted in an area suitable for planting winter wheat, and then the two parents are hybridized, and the harvested wheat is used as the F0 generation; The third step is to backcross the F0 generation with high-quality wheat to obtain the backcross F0 generation: During the normal winter wheat planting season, the F0 generation and high-quality wheat parents are planted in the field. The F0 generation wheat is tested for molecular markers that are missing glutenin 5+10, 7+8, 17+18 subunits and secalin. Wheat containing the relevant markers is used as the female parent and backcrossed with the high-quality parent. After maturity, the backcross F0 generation seeds are obtained; The fourth step is to backcross the F0 and plant it again to get the F1 generation: Planting backcross F0 generation wheat in the field and harvesting to obtain F1 generation, testing glutenin 5+10, 7+8, 17+18 subunits and secalin deficiency molecular markers before harvesting, and selecting wheat containing glutenin high-quality subunits and secalin deficiency molecular markers as F1 generation; Step 5: Screening high-quality marked wheat varieties: (1) In the early F2 generation, heterosis of the combinations was observed and molecular markers of glutelin 5+10, 7+8, 17+18 subunits and secalin deficiency were detected; (2) In the early F3 generation, individual plants were selected and the molecular markers of glutenin high-quality subunits and secalin deficiency were tested for the selected individual plants. 40-50 g of seeds were sampled from the lines with molecular markers to determine the gluten index, and the materials with a gluten index of more than 90% were selected; (3) For the early F4 generation, select individual plants and excellent strains, using Heng 4399, Jimai 22, and Heshiluan 02-1 as controls, and focus on selecting individual plants with strong tillering ability, number of grains per ear ≥40, 1,000-grain weight ≥40g, full grains, good cold resistance, and good plant type. Continue to test for molecular markers of glutenin high-quality subunits and secalin deficiency. Select 40-50g seeds of key strains to test the gluten index, and screen materials with a gluten index of more than 90%. For materials that meet the standards, select 120 seeds, divide them into three portions, 40 seeds each, and select three locations within Baoding City for cold resistance screening; (IV) For the F5-F7 generations, select individual plants and select excellent strains. Using Heng 4399, Jimai 22, and Shiluan 02-1 as controls, focus on selecting individual plants with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance, and good plant type. Continue to test for gluten subunits and secalin deficiency molecular markers. For all screened strains, select 40-50g of seeds to test the gluten index, and select materials with a gluten index of more than 90%. For materials that meet the standards, select 120 seeds, divide them into three portions, 40 seeds each, and select three locations within Baoding City for cold resistance screening. The sixth step is to identify water-saving performance under different water conditions, select strains with good water-saving performance, and conduct resistance identification on key materials: (1) Identify the high yield and quality of the strains selected from the F4-F7 generations Identification conditions: Three treatments (0 spring watering, 1 spring watering, and 2 spring watering) were set up without replication. Heng 4399, Jimai 22, and Shiluan 02-1 were used as controls to conduct water-saving and high-yield quality and stress resistance identification. The materials were evaluated for drought resistance, water-saving properties, and high yield. The quality stability of the materials and the molecular markers for the deletion of glutenin 5+10, 7+8, 17+18 subunits, and secalin were also tested. Selection index of drought resistance and water-saving index: for drought resistance, materials with better yield than the control under 0 water treatment were selected, with 3% as the screening index, and materials with more than 3% were selected, and the percentage value was directly taken, that is, yield increase of x% was marked as x; for water-saving, materials with better yield than the control under 1 water treatment were selected, with 3% as the screening index, and materials with more than 3% were selected, and the percentage value was directly taken, that is, yield increase of y% was marked as y; at the same time, the water-saving index WSI was calculated based on the yield results of 1 water and 2 water treatment conditions, and finally the drought resistance and water-saving index selection index DWUI=x*y*WSI was formed, and varieties with DWUI values ​​greater than 10 were selected. At the same time, the following conditions must be met: TaRa-F, TaRa-R, TaRb-F, and TaRb-R molecular detection was carried out after the F5 generation, that is, varieties with the above molecular markers were selected among varieties with DWUI values ​​greater than 10; the calculation formula of the WSI water-saving index is WSI=Y a 4 *Y m -1 *Y M *(Y A 4 ) -1 , where Y a is the grain yield of the tested material under stress treatment (kg), Y m Grain yield of the tested material control treatment (kg), Y M is the grain yield of the control variety and the control treatment (kg), Y A is the grain yield of the control variety under stress treatment (kg); High-yield identification: Using Heng 4399 and Jimai 22 as controls, focus on selecting individual plants or strains with strong tillering ability, number of grains per ear ≥40, 1000-grain weight ≥40g, full grains, good cold resistance, and good plant shape; Quality stability identification: Using Shiluan 02-1 as a control, test the gluten index, select the gluten index > 90%, and identify and track the molecular markers of glutenin superior subunits and secalin deficiency; (2) Identify the cold resistance and disease and insect resistance of the strains selected from the F4-F7 generations Cold resistance identification conditions: Cold resistance was identified at three locations within the Baoding area of ​​the central and northern Hebei wheat region. Materials with good cold resistance were selected, and varieties with a cold resistance index >= 1 were selected. Vernalization gene testing was also conducted to test the winter-spring characteristics of the varieties. Cold resistance index CRI: With the dead stem rate as a reference, the cold resistance index is formed. The specific formula is: (0.2 / dead stem rate of the test material) the average value of the three sites; Identification of disease and insect resistance: 150 seeds of each strain were selected and divided into three parts, with 50 seeds in each part, for identification of powdery mildew, stripe rust and leaf rust. Among the three diseases, the ones with one reaching medium resistance or above, or two reaching medium susceptibility or above can be selected.

2. The method for selective breeding according to claim 1, characterized in that: Choose varieties with a cold resistance index of >= 2.

1.

3. The method for selective breeding according to claim 1, characterized in that: The F0-F2 generations can be carried out under plus generation conditions to improve efficiency.