Breeding method of spring rape variety suitable for large-density planting

Abstract

The invention relates to the technical field of agricultural cultivation, and particularly discloses a spring rape variety breeding method suitable for large-density planting, which comprises the following steps: collecting and establishing a germplasm resource library, performing preliminary screening according to local conditions, evaluating the growth speed, close planting resistance, disease resistance and quality in detail, and screening out excellent germplasm resources; selecting parents according to germplasm resource characters, designing a hybridization combination scheme, and performing artificial hybridization operation to obtain filial generations; filial generation F1-generation microspores are extracted for in-vitro culture, haplobionts are obtained and doubled into a homozygous DH line, and plants meeting the breeding target are screened out; designing a high-density planting test scheme, carrying out a planting test, regularly observing and recording plant characters, and screening out a spring rape variety which is excellent in performance and meets a breeding target; the breeding steps of the system comprise germplasm resource screening, hybrid combination construction, microspore culture, DH line breeding and high-density planting test and screening.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural cultivation, and in particular relates to a method for breeding spring rapeseed varieties suitable for high-density planting. Background Art

[0002] In the field of rapeseed cultivation, traditional spring rapeseed varieties are often not suitable for high-density planting patterns, and have problems such as stunted growth, reduced yields, and poor quality. With the increasing degree of agricultural intensification and the increasing shortage of land resources, how to improve the yield and quality of rapeseed on limited land has become an important issue in current rapeseed breeding.

[0003] Traditional breeding methods have a long cycle, low efficiency, and it is difficult to accurately breed spring rapeseed varieties suitable for high-density planting. Therefore, there is an urgent need for an efficient and accurate breeding method to meet the needs of modern agriculture for high-yield and high-quality spring rapeseed varieties. Summary of the invention

[0004] The object of the present invention is to provide a method for breeding spring rapeseed varieties suitable for high-density planting, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for breeding spring rapeseed varieties suitable for high-density planting comprises the following steps:

[0007] S1. Collect and establish a germplasm resource bank, conduct preliminary screening based on local conditions, and conduct detailed evaluation of growth rate, tolerance to dense planting, disease resistance and quality to select high-quality germplasm resources;

[0008] S2. Select parents according to the characteristics of germplasm resources, design hybrid combination schemes, perform artificial hybridization operations, and obtain hybrid offspring;

[0009] S3, extracting the microspores of the hybrid offspring F1 generation for in vitro culture, obtaining haploid plants and doubling them into homozygous DH lines, and selecting plants that meet the breeding goals;

[0010] S4. Design a high-density planting test plan, conduct planting tests, regularly observe and record plant traits, and screen out spring rapeseed varieties with excellent performance that meet breeding goals.

[0011] Preferably, in S1, the germplasm resource screening specifically includes:

[0012] S11. Collect spring rapeseed varieties and establish a germplasm resource bank;

[0013] S12. Conduct preliminary screening of the collected germplasm resources according to the local climate, soil, and cultivation habits;

[0014] S13. Evaluate the growth rate, tolerance to dense planting, disease resistance and quality of the germplasm resources initially screened.

[0015] Preferably, in S2, the hybrid combination construction specifically includes:

[0016] S21, according to the trait performance of the germplasm resources screened in step 1, selecting parents with large genetic background differences and complementary traits for hybridization;

[0017] S22. Perform artificial hybridization operations according to the designed hybridization combination scheme to obtain hybrid offspring.

[0018] Preferably, in S3, microspore culture and DH line breeding specifically include:

[0019] S31, taking the flower buds of the F1 generation of the hybrid offspring, extracting microspores for in vitro culture, and obtaining haploid plants;

[0020] S32, performing chromosome doubling treatment on the obtained haploid plants to restore them to diploid, and obtaining a homozygous DH line;

[0021] S33. In the DH line, plants that meet the breeding goals are selected as the basic material for subsequent breeding based on plant height, stem thickness, branching, leaf distribution and tolerance to dense planting.

[0022] Preferably, in S4, the high-density planting test and screening specifically include:

[0023] S41. Design a high-density planting test plan based on breeding objectives, including planting density, planting method, and fertilization management;

[0024] S42, according to the designed test plan, the selected DH series plants are subjected to a high-density planting test;

[0025] S43. During the test, regularly observe the growth performance, yield traits and quality traits of the plants, and record and analyze them;

[0026] S44. Based on the observation and evaluation results, spring rapeseed varieties that perform well under high-density planting conditions and meet the breeding goals are selected.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The present invention can efficiently breed spring rapeseed varieties suitable for high-density planting through systematic breeding steps, including germplasm resource screening, hybrid combination construction, microspore culture and DH line breeding, and high-density planting test and screening. Compared with traditional breeding methods, the breeding cycle is shortened and the breeding efficiency is improved.

[0029] (2) During the breeding process, the present invention focuses on detailed evaluation and screening of germplasm resources, as well as testing and observation under high-density planting conditions, and can accurately breed spring rapeseed varieties that meet the breeding goals. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Embodiment 1:

[0033] See also Figure 1 As shown, a method for breeding spring rapeseed varieties suitable for high-density planting comprises the following steps:

[0034] S1. Collect and establish a germplasm resource bank, conduct preliminary screening based on local conditions, and conduct detailed evaluation of growth rate, tolerance to dense planting, disease resistance and quality to select high-quality germplasm resources;

[0035] S2. Select parents according to the characteristics of germplasm resources, design hybrid combination schemes, perform artificial hybridization operations, and obtain hybrid offspring;

[0036] S3, extracting the microspores of the hybrid offspring F1 generation for in vitro culture, obtaining haploid plants and doubling them into homozygous DH lines, and selecting plants that meet the breeding goals;

[0037] S4. Design a high-density planting test plan, conduct planting tests, regularly observe and record plant traits, and screen out spring rapeseed varieties with excellent performance that meet breeding goals.

[0038] In one embodiment of the present invention, germplasm resource screening specifically includes:

[0039] S11. Collect spring rapeseed varieties and establish a germplasm resource bank;

[0040] S12. Conduct preliminary screening of the collected germplasm resources according to the local climate, soil, and cultivation habits;

[0041] S13. Evaluate the growth rate, tolerance to dense planting, disease resistance and quality of the germplasm resources initially screened.

[0042] In one embodiment of the present invention, the hybrid combination construction specifically includes:

[0043] S21, according to the trait performance of the germplasm resources screened in step 1, selecting parents with large genetic background differences and complementary traits for hybridization;

[0044] S22, performing artificial hybridization operations according to the designed hybridization combination scheme to obtain hybrid offspring, specifically including:

[0045] According to the breeding objectives and the results of germplasm resource analysis, parents with large differences in genetic background and complementary traits are selected for hybridization;

[0046] The design of hybrid combinations takes into account the genetic differences and trait complementarity between the parents, as well as the possible hybrid vigor and genetic effects.

[0047] In one embodiment of the present invention, microspore culture and DH line breeding specifically include:

[0048] S31, taking the flower buds of the F1 generation of the hybrid offspring, extracting microspores for in vitro culture, and obtaining haploid plants;

[0049] S32, performing chromosome doubling treatment on the obtained haploid plants to restore them to diploid, and obtaining a homozygous DH line;

[0050] S33. In the DH series, plants that meet the breeding goals are selected as the basic materials for subsequent breeding based on plant height, stem thickness, branching, leaf distribution and tolerance to dense planting, including:

[0051] The weights of plant height, stem thickness, branching, leaf distribution and tolerance to dense planting are set as w1=w2=w3=w4=w5=1 respectively;

[0052] According to the actual breeding goals, the weight is adjusted through expert scoring or data analysis, and the adjustment coefficient is k i , then the adjusted weight is w i '=k i w i ;

[0053] To this end, we comprehensively consider plant height (H), stem thickness (S), branching (B), leaf distribution (L) and dense planting tolerance index (D) to select plants that meet the breeding goals. The specific algorithm is as follows:

[0054]

[0055] Among them, SI is the breeding index, which is used to measure the comprehensive breeding value of the plant; H is the height of the plant, in centimeters (cm), which is a direct indicator of the growth status of the plant; S is the diameter of the stem, in millimeters (mm), which reflects the mechanical strength of the stem; B is the number of branches of the plant, which is a dimensionless integer, indicating the branching ability of the plant; L is the average distribution height of the leaves on the plant (the average distance from the ground to the center of the leaf), in centimeters (cm), reflecting the leaf layout of the plant; D is the growth performance score of the plant under a specific density, which is a dimensionless value. The higher the score, the better the tolerance to dense planting;

[0056] Setting the breeding index threshold SI th , only when SI ≥ SI th The higher the SI value, the better the overall performance of the plant in terms of plant height, stem thickness, branching, leaf distribution and tolerance to dense planting, and the more it meets the breeding goals.

[0057] In one embodiment of the present invention, the high-density planting test and screening specifically include:

[0058] S41. Design a high-density planting test plan based on breeding objectives, including planting density, planting method, and fertilization management;

[0059] S42, according to the designed test plan, the selected DH series plants are subjected to a high-density planting test;

[0060] S43. During the test, regularly observe the growth performance, yield traits and quality traits of the plants, and record and analyze them;

[0061] S44. Based on the observation and evaluation results, spring rapeseed varieties that perform well under high-density planting conditions and meet the breeding goals are selected, including:

[0062] First, consider the basic growth performance, yield traits and quality traits, as well as their weights and changes over time. The algorithm is as follows:

[0063]

[0064] Among them, P(x, y, z, t) is a comprehensive evaluation index, which indicates the comprehensive performance of spring rapeseed varieties under high-density planting conditions. The higher the value, the better the performance. x, y, z represent the quantitative indicators of planting density, planting method and fertilization management, respectively. t represents time, indicating the observation and evaluation cycle. T is the total observation time. N is the number of growth performance, yield trait and quality trait indicators. G i(x, y) is the function of the ith growth performance or yield trait index with respect to planting density and planting method; λ is the attenuation coefficient, which indicates the rate of change of the index over time; t i is the observation time of the i-th indicator;

[0065] Taking into account the effect of planting depth on growth performance, the algorithm is as follows:

[0066]

[0067] Among them, H i is the relationship function between the i-th index and the planting depth z; μ is the weight coefficient of the quality trait index; F j (z, t) is the function of the j-th quality trait index with respect to planting depth and time, M is the number of quality trait indexes, and A is the area of ​​the planting region.

[0068] Finally, considering the influence of factors such as soil and climate in the planting area on the comprehensive evaluation index, the algorithm is as follows:

[0069]

[0070] in, is the gradient operator; Q k (x, y, z) is a function that represents the influence of soil, climate and other factors in the planting area; L is the number of soil, climate and other factors.

[0071] Experimental example:

[0072] Germplasm resource screening: 100 spring rapeseed germplasm resources from different regions were collected to establish a germplasm resource bank. According to the local climate (average annual temperature and precipitation), soil (soil type and pH value) and cultivation habits, the collected germplasm resources were preliminarily screened and 30 with strong adaptability were retained;

[0073] The 30 germplasm resources initially selected were evaluated in detail for growth rate, tolerance to dense planting, disease resistance and quality. The evaluation methods included field trials, laboratory tests and expert scoring, and finally 5 high-quality germplasm resources were selected;

[0074] Hybrid combination construction: Based on the trait performance of the five selected germplasm resources, two parents with large genetic background differences and complementary traits were selected for hybridization, a hybrid combination scheme was designed, and artificial hybridization operations were performed to obtain a total of two hybrid combination offspring;

[0075] Microspore culture and DH line breeding: Take the F1 generation flower buds of the hybrid offspring, extract the microspores for in vitro culture, and obtain haploid plants. 50 haploid plants were cultured together, and the chromosomes of the obtained haploid plants were doubled to restore them to diploid, and homozygous DH lines were obtained. After the doubling treatment, 25 homozygous DH lines were successfully obtained;

[0076] In the DH series, we screened based on plant height, stem thickness, branching, leaf distribution, and tolerance to dense planting. Through expert scoring and data analysis, we selected five plants that met the breeding goals as the basic materials for subsequent breeding.

[0077] High-density planting test and screening: Design a high-density planting test plan with a planting density of 80,000 plants per mu, adopt row sowing, and fertilization management according to local recommended standards. The 5 selected DH series plants will be subjected to high-density planting tests, with 3 replicate plots of each variety, and each plot has an area of ​​20 square meters;

[0078] During the experiment, the growth performance of the plants (such as plant height, stem thickness, number of leaves, etc.), yield traits (such as yield per unit area, 1000-grain weight, etc.) and quality traits (such as oil content, protein content, etc.) were regularly observed, recorded and analyzed.

[0079] Experimental results and analysis:

[0080] Under high-density planting conditions, the growth indicators of each variety, such as plant height, stem diameter and number of leaves, were different. Among them, variety A had the highest plant height, reaching 160 cm; variety B had the thickest stem diameter, which was 1.5 cm; variety C had the most leaves, 25 leaves per plant;

[0081] After harvesting and yield measurement, the yield per unit area and 1000-grain weight of each variety are as follows: the yield per unit area of ​​variety A is 300 kg / mu, and the 1000-grain weight is 4.5 g; the yield per unit area of ​​variety B is 280 kg / mu, and the 1000-grain weight is 4.2 g; the yield per unit area of ​​variety C is 260 kg / mu, and the 1000-grain weight is 4.0 g;

[0082] The quality traits of each variety were tested and analyzed, and the results were as follows: the oil content of variety A was 45%, and the protein content was 22%; the oil content of variety B was 43%, and the protein content was 23%; the oil content of variety C was 42%, and the protein content was 24%.

[0083] From the above, we can see that variety A performs well in growth rate, yield and quality, especially under high-density planting conditions, it can still maintain good yield and quality. Therefore, variety A will be promoted and applied as a spring rapeseed variety that meets the breeding goals.

[0084] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for breeding spring rapeseed varieties suitable for high-density planting, characterized in that: The following steps are involved: S1. Collect and establish a germplasm resource bank, conduct preliminary screening based on local conditions, and conduct detailed evaluation of growth rate, tolerance to dense planting, disease resistance and quality to select high-quality germplasm resources; S2. Select parents according to the characteristics of germplasm resources, design hybrid combination schemes, perform artificial hybridization operations, and obtain hybrid offspring; S3, extracting the microspores of the hybrid offspring F1 generation for in vitro culture, obtaining haploid plants and doubling them into homozygous DH lines, and selecting plants that meet the breeding goals; S4. Design a high-density planting test plan, conduct planting tests, regularly observe and record plant traits, and screen out spring rapeseed varieties with excellent performance that meet breeding goals.

2. The method for breeding spring rapeseed varieties suitable for high-density planting according to claim 1, characterized in that: In S1, the germplasm resource screening specifically includes: S11. Collect spring rapeseed varieties and establish a germplasm resource bank; S12. Conduct preliminary screening of the collected germplasm resources according to the local climate, soil, and cultivation habits; S13. Evaluate the growth rate, tolerance to dense planting, disease resistance and quality of the germplasm resources initially screened.

3. The method for breeding spring rapeseed varieties suitable for high-density planting according to claim 1, characterized in that: In said S2, the hybrid combination construction specifically includes: S21, according to the trait performance of the germplasm resources screened in step 1, selecting parents with large genetic background differences and complementary traits for hybridization; S22. Perform artificial hybridization operations according to the designed hybridization combination scheme to obtain hybrid offspring.

4. The method for breeding spring rapeseed varieties suitable for high-density planting according to claim 1, characterized in that: In S3, microspore culture and DH line breeding specifically include: S31, taking the flower buds of the F1 generation of the hybrid offspring, extracting microspores for in vitro culture, and obtaining haploid plants; S32, performing chromosome doubling treatment on the obtained haploid plants to restore them to diploid, and obtaining a homozygous DH line; S33. In the DH line, plants that meet the breeding goals are selected as the basic material for subsequent breeding based on plant height, stem thickness, branching, leaf distribution and tolerance to dense planting.

5. The method for breeding spring rapeseed varieties suitable for high-density planting according to claim 1, characterized in that: In said S4, the high-density planting test and screening specifically include: S41. Design a high-density planting test plan based on breeding objectives, including planting density, planting method, and fertilization management; S42, according to the designed test plan, the selected DH series plants are subjected to a high-density planting test; S43. During the test, regularly observe the growth performance, yield traits and quality traits of the plants, and record and analyze them; S44. Based on the observation and evaluation results, spring rapeseed varieties that perform well under high-density planting conditions and meet the breeding goals are selected.

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