A method for broadening the genetic basis of dwarf bunt resistant wheat by selecting elite germplasm

Abstract

The application discloses a method for widening the genetic basis of dwarf sterile wheat and selecting excellent germplasm, which comprises the following steps: S1, screening more than 300 donor parent materials with rich genetic basis from wheat micro-core germplasm resources or core germplasm resources; S2, sowing the donor parent materials in three sowing periods; S3, pollinating a wheat basic dwarf group with the donor parent materials in the flowering period of the donor parent materials; S4, harvesting the ears of all dwarf plants in the wheat basic dwarf group in the mature period, mixing and threshing the ears to form a dwarf group with rich genetic basis; and S5, repeating the planting of the obtained dwarf group as the wheat basic dwarf group, and performing stress treatment to select high-quality germplasm lines. The method has the advantages that the genetic basis of the dwarf group is effectively widened, excellent wheat germplasm materials are identified according to the dwarf group with rich genetic basis, and the dwarf sterile plants and the high sterile plants are subjected to drought resistance, heat resistance, cold resistance and pathogenic bacteria inoculation resistance identification, so that the excellent wheat germplasm materials can better serve the wheat breeding practice.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dwarf sterile wheat population construction and excellent germplasm creation, and particularly relates to a method for breeding excellent germplasm by widening the genetic basis of dwarf sterile wheat. BACKGROUND

[0002] Dwarf sterile wheat is a Taigu cytoplasmic male sterile wheat with dwarf gene markers created by Liu Binghua, a researcher of the Crop Research Institute of Chinese Academy of Agricultural Sciences, which has the advantages of complete male sterility, stable sterility and high cross-pollination rate, and has been well applied in China. At present, there are two main application methods, one is to carry out directional improvement of dwarf sterile population by bagging hybridization with fertile wheat germplasm, and the other is to improve the genetic population structure of crops by cyclically selecting and hybridizing multiple times. In self-pollinated crops such as wheat, a few core parents are generally used as exogenous germplasm to hybridize with dwarf sterile population to prepare original population, and then the population is improved by the method of recurrent selection.

[0003] There are more than 50,000 wheat germplasm resources in China, but many of them have not been well identified and cannot be effectively used in breeding practice, because it is very difficult to identify tens of thousands of germplasm resources. Based on this, some experts and scholars have screened 1600 core germplasms according to the preliminary identification traits, and nearly 300 core germplasms have been screened out by molecular markers, but even so, it is very difficult to finely identify them in multiple stress projects. It is a laborious and costly thing to identify 300 or so micro-core germplasms or 1600 core germplasms in a certain index, and only 2-3 useful germplasms may be obtained, and the genetic background is very poor. SUMMARY

[0004] The purpose of the present application is to provide a method for breeding excellent germplasm by widening the genetic basis of dwarf sterile wheat, thereby solving the aforementioned problems in the prior art.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0006] A method for breeding excellent germplasm by widening the genetic basis of dwarf sterile wheat, comprising the following steps,

[0007] S1, selecting more than 300 donor parent materials with rich genetic basis from wheat micro-core germplasm resources or core germplasm resources;

[0008] S2, the donor parent material is sown in three sowing periods; in the first sowing period, the donor parent material is sown at the same time as the wheat basic dwarf failure group; in the second sowing period, the donor parent material is sown one week later than the wheat basic dwarf failure group; in the third sowing period, the donor parent material is sown two weeks later than the wheat basic dwarf failure group, so that the donor parent material with different flowering periods has the opportunity to provide pollen for the wheat basic dwarf failure group;

[0009] S3, in the flowering period of the donor parent material in different sowing periods, the wheat basic dwarf failure group is pollinated with the donor parent material;

[0010] S4, in the mature period, all the dwarf plants in the wheat basic dwarf failure group are harvested and threshed to form a genetic basic rich dwarf failure group;

[0011] S5, the obtained genetic basic rich dwarf failure group is used as the wheat basic dwarf failure group, and the sowing is repeated for 1-2 years according to steps S1-S4, and stress treatment under multiple conditions is carried out, so as to screen high plants and dwarf plants with good comprehensive resistance, and after selfing and stabilization, a high-quality germplasm line with rich genetic basis is obtained.

[0012] Preferably, the wheat basic dwarf failure group is planted in two rows, and different donor parent materials are planted in the field in a perpendicular manner with the wheat basic dwarf failure group.

[0013] Preferably, the donor parent material is horizontally planted, and the wheat basic dwarf failure group is vertically planted.

[0014] Preferably, in the pollination, the ears of the dwarf plants in the wheat basic dwarf failure group are trimmed, because the ears of the dwarf plants have no anther, so there is no need to emasculation, so that the stigma of the dwarf plants is more exposed, and the probability of pollen falling on the stigma is improved.

[0015] Preferably, the trimming of the ears of the dwarf plants in the wheat basic dwarf failure group is that the pericarp of each dwarf plant ear is cut off by 1 / 3 from the top with scissors.

[0016] Preferably, in the pollination, the exposed bright yellow anthers of the ears of the donor parent material are lightly tapped towards the wheat basic dwarf failure group with a tool, or the exposed bright yellow anthers of the ears of the donor parent material are blown towards the wheat basic dwarf failure group to simulate a strong wind, so as to assist the pollen of the donor parent material to better fall on the stigma of the wheat basic dwarf failure group.

[0017] The beneficial effects of the present application are: the genetic basis of the dwarf failure group is effectively widened, according to the constructed genetic basic rich dwarf failure group, through drought resistance, heat resistance, cold resistance and disease resistance identification of dwarf sterile plants and high fertile plants, excellent wheat germplasm materials are identified, and better service is provided for wheat breeding practice. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a flow chart of the method in the embodiments of the present application;

[0019] Figure 2 is a schematic diagram of the wheat planting method in the embodiments of the present application;

[0020] Figure 3 is a schematic diagram of the dwarf failure population and excellent line in the embodiments of the present application;

[0021] Figure 4 is a field photo of Qingyanlanmai No. 1 in the embodiments of the present application;

[0022] Figure 5 is a grain photo of Qingyanlanmai No. 1 in the embodiments of the present application. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0024] As shown in Figure 1 , in the embodiments, a method for widening the genetic basis of dwarf failure wheat and selecting excellent germplasm is provided, which comprises the following steps,

[0025] S1, selecting more than 300 donor parent materials with rich genetic basis from wheat micro-core germplasm resources or core germplasm resources;

[0026] S2, sowing the donor parent materials in three sowing periods; in the first sowing period, the donor parent materials are sown at the same time as the wheat basic dwarf failure population; in the second sowing period, the donor parent materials are sown about one week later than the wheat basic dwarf failure population; in the third sowing period, the donor parent materials are sown about two weeks later than the wheat basic dwarf failure population, so that the donor parent materials with different flowering periods have the opportunity to provide pollen to the wheat basic dwarf failure population, and on the other hand, the repetition is increased to some extent, and the pollen supply efficiency of the donor parent materials is improved.

[0027] In the embodiments, the wheat basic dwarf failure population is planted in two rows, and different donor parent materials are planted in the field in a perpendicular manner with the wheat basic dwarf failure population. Referring to Figure 2 , the donor parent materials are planted horizontally, sowed at 50 cm, 10 seeds per sowing, and the wheat basic dwarf failure population is planted vertically.

[0028] S3, in the flowering period of the donor parent materials in different sowing periods, the donor parent materials are used to pollinate the wheat basic dwarf failure population.

[0029] At the time of pollination, the lemma of each spike of the dwarf plant in the wheat basic dwarf failure population is cut off about 1 / 3 from the top with scissors, so that the stigma of the dwarf plant is more exposed, and the probability of pollen falling on the stigma is increased. Since the spike of the dwarf plant has no anther, it is not necessary to emasculate.

[0030] At the same time, the spike with bright yellow anther in the donor parent material is lightly tapped towards the wheat basic dwarf failure population with a tool (such as a bamboo pole), or the spike with bright yellow anther in the donor parent material is blown towards the wheat basic dwarf failure population to simulate a strong wind, so as to assist the pollen of the donor parent material to better fall on the stigma of the wheat basic dwarf failure population.

[0031] S4, at the mature stage, the spikes of all dwarf plants in the wheat basic dwarf failure population are harvested and mixed to thresh, to form a genetic basic rich dwarf failure population;

[0032] S5, the obtained genetic basic rich dwarf failure population is planted again according to the steps S1-S4 for 1-2 years, to obtain more opportunities for free cross pollination, and the obtained genetic basic rich dwarf failure population is subjected to stress treatment under multiple conditions, to screen high plants and dwarf plants with good comprehensive resistance, and after selfing and stabilization, a high-quality germplasm line with rich genetic basis is obtained. Alternatively, the obtained genetic basic rich dwarf failure population can be directly subjected to stress treatment under multiple conditions, to screen high plants (tall fertile plants) and dwarf plants (short sterile plants) with good comprehensive resistance, and a high-quality germplasm line with rich genetic basis is obtained.

[0033] In this embodiment, a genetic basic rich dwarf failure wheat population is obtained by the method of the application, as shown in the accompanying Figure 3 , the plant height is from 50 cm to 110 cm, the thousand-grain weight is 25 g-55 g, or even 60 g, the grain color covers common white wheat, red wheat, purple grain wheat, blue grain wheat, etc., the grain color, size and traits are very rich, and the dwarf failure genetic basis is widened. Not only various types of germplasm are obtained, but also a blue wheat line Qingyan Blue Wheat No. 1 is obtained, and the quality index reaches the high-quality strong gluten level. The field photo and grain photo of Qingyan Blue Wheat No. 1 are shown in Figure 4 and Figure 5 .

[0034] In this embodiment, the method of the application focuses on using dwarf wheat tool population, shuttle planting in more than 300 wheat micro-core germplasm and important parent population, free pollination, continuous free pollination for 2 years, and then selfing for 1 year, to obtain a wheat improvement population with a particularly rich genetic basis. Then take high plant normal fertile seeds and dwarf sterile seeds to carry out salt, drought, low temperature, high temperature stress and related disease inoculation identification, and obtain excellent disease-resistant and stress-resistant dwarf sterile population and excellent intermediate germplasm material for wheat breeding practice. Compared with the existing method, on the one hand, the genetic basis of the population can be greatly widened due to the large population of wheat core germplasm and important parents; secondly, a small amount of population or seed can be used for stress identification, which saves the direct identification and evaluation of existing large-scale germplasm, and we do not need to identify existing variety resources, but directly obtain excellent trait germplasm. The outstanding advantages are: the identified materials are greatly reduced, because one seed may represent a different genotype, greatly reducing the workload, so even if only 2-3 are identified in one round, it will not feel very regrettable, and the identified materials are excellent. Then combine double haploid technology to realize the rapid and stable selection of the selected dwarf sterile materials; or obtain stable germplasm by systematic breeding method. The germplasm obtained in this way combines the genes of hundreds or even thousands of wheat resources, and the genetic background will be very rich.

[0035] By adopting the above technical solutions disclosed in the application, the following beneficial effects are obtained:

[0036] The application provides a method for widening excellent germplasm of dwarf sterile wheat genetic breeding, which effectively widens the genetic basis of the dwarf sterile population. According to the constructed dwarf sterile population with rich genetic basis, the excellent wheat germplasm material is identified through the technologies of drought resistance, heat resistance, cold resistance, disease resistance identification by inoculating pathogenic bacteria and the like, so as to better serve the wheat breeding practice.

[0037] The above description is only the preferred embodiment of the application, and it should be pointed out that for ordinary skilled persons in the technical field, some improvements and refinements can be made without departing from the principle of the application, and these improvements and refinements should be regarded as the protection scope of the application.

Claims

1. A method of broadening the genetic base of dwarf bunt resistant wheat by selecting elite germplasm, characterized by: Comprising the following steps, S1, screening more than 300 donor parent materials with rich genetic basis from wheat micro-core germplasm resources or core germplasm resources; S2, sowing the donor parent materials in three sowing periods; in the first sowing period, the donor parent materials are sown at the same time as the wheat basic dwarf failure population; in the second sowing period, the donor parent materials are sown one week later than the wheat basic dwarf failure population; in the third sowing period, the donor parent materials are sown two weeks later than the wheat basic dwarf failure population, so that the donor parent materials with different flowering periods have the opportunity to provide pollen for the wheat basic dwarf failure population; S3, pollinating the wheat basic dwarf failure population with the donor parent materials at the flowering stage of the donor parent materials in different sowing periods; S4, harvesting all the dwarf plants in the wheat basic dwarf failure population at the mature stage, mixing and threshing the ears to form a dwarf failure population with rich genetic basis; S5, taking the obtained dwarf failure population with rich genetic basis as the wheat basic dwarf failure population, repeating the sowing according to steps S1-S4 for 1-2 years, and then performing stress treatment under multiple conditions to screen high and dwarf plants with good comprehensive resistance, and obtaining high-quality germplasm lines with rich genetic basis after selfing and stabilization; planting the wheat basic dwarf failure population in two rows, and planting different donor parent materials and the wheat basic dwarf failure population in the field in a perpendicular manner; the donor parent materials are horizontally planted, and the wheat basic dwarf failure population is vertically transplanted.

2. The method of broadening the genetic base of elite germplasm of wheat by introgression of dwarfing genes as claimed in claim 1 wherein: When pollinating, the ears of the dwarf plants in the wheat basic dwarf failure population are pruned, because the ears of the dwarf plants have no anthers, so there is no need to emasculate, which makes the stigma of the dwarf plants more exposed and improves the probability of pollen falling on the stigma.

3. The method of broadening the genetic base of elite germplasm of wheat by introgression of dwarfing genes as claimed in claim 2, wherein: The pruning of the ears of the dwarf plants in the wheat basic dwarf failure population is specifically that the sheath of each dwarf plant ear is cut off by 1 / 3 from the top with scissors.

4. The method of broadening the genetic base of elite germplasm of wheat as claimed in claim 3, wherein: When pollinating, the exposed bright yellow anthers of the ears of the donor parent materials are lightly tapped towards the wheat basic dwarf failure population with a tool, or the exposed bright yellow anthers of the ears of the donor parent materials are blown towards the wheat basic dwarf failure population to simulate a strong wind, so as to assist the pollen of the donor parent materials to better fall on the stigma of the wheat basic dwarf failure population.

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