阅读说明：本技术 一种异源多倍体小黑麦种质的育种方法 (Breeding method of allopolyploid triticale germplasm ) 是由 孟凡华 游光霞 杨丽 李桂英 刘秉华 王增远 孙元枢 于 2020-12-24 设计创作，主要内容包括：本发明公开了一种异源多倍体小黑麦种质的育种方法,将染色体构型为RR的二倍体黑麦用秋水仙素处理,得到染色体RRRR型四倍体黑麦,以染色体RRRR型四倍体黑麦为父本,染色体AABB型四倍体硬粒小麦为母本杂交,即得多倍体小黑麦种质资源。通过本方案得到的多倍体小黑麦新种质结合了小麦的矮秆、丰产、硬质性状和黑麦的抗三锈、抗白粉病特性,为通心粉小黑麦品种的培育奠定了材料基础,拓展了小黑麦的利用空间。(The invention discloses a breeding method of an allopolyploid triticale germplasm, which comprises the steps of treating diploid rye with RR in chromosome configuration to obtain chromosome RRRR type tetraploid rye, and hybridizing with chromosome RRRR type tetraploid rye as a male parent and chromosome AABB type tetraploid durum as a female parent to obtain the polyploid triticale germplasm resource. The novel polyploid triticale germplasm obtained by the scheme combines the characteristics of short stalk, high yield and hard property of wheat and the characteristics of three rust resistance and powdery mildew resistance of rye, lays a material foundation for cultivating the macaroni triticale variety, and expands the utilization space of the triticale.)

1. A breeding method of allopolyploid triticale germplasm is characterized in that diploid rye with a chromosome configuration of RR is treated by colchicine to obtain chromosome RRRR type tetraploid rye, and the chromosome RRRR type tetraploid rye is taken as a male parent and chromosome AABB type tetraploid durum is taken as a female parent for hybridization to obtain the polyploid triticale germplasm resource.

2. The method of claim 1, wherein said RR type diploid rye is preferably B e r х H (By) ч c (Bb a).

3. The method of claim 1, wherein said RRRR-type tetraploid rye is preferably rye ZS 507.

4. The method of claim 1, wherein said chromosomal AABB type tetraploid durum wheat is preferably tetraploid durum wheat di, a tetraploid durum wheat a, a.

5. The method of claim 4, wherein said tetraploid durum wheat di/a hybridizes with rye ZS507 to obtain AABBRRRR type octaploid triticale.

6. The method of claim 5, wherein said tetraploid durum wheat M a is hybridized with said rye ZS507 to obtain F a₀Generation of seed, F₀Sowing the seeds in field, and sowing the seeds in the field to obtain hybrid chromosome ABRR type F₁Plants, and AABBRR type hexaploid triticale pollen is awarded to obtain AABBRR type hexaploid triticale and AARR and BBRR type tetraploid triticale; or pollen granted to AABBRRRR type octaploid triticale to obtain AABBRRRR type octaploid triticale.

7. The method of claim 6, wherein the AABBRR hexaploid small rye is obtained by hybridizing tetraploid durum wheat ion and.

Technical Field

The invention belongs to the technical field of wheat breeding, and particularly relates to a breeding method of an allopolyploid triticale germplasm.

Background

In 1888, wheat-rye hybrid Rimpau was obtained for the first time in Germany breeding Bolin castle (Rimpau),in 1935, the swedish geneticist a. muttzing identified the first wheat-rye double-diploid system in the world, Rimpau, at the cytological level, as an allooctaploid triticale. Before and after 1957, Mr. Bovingqua hybridized with wheat "China spring" (chromosome organization type AABBDD) and rye (RR), hybrid F₁After artificial doubling, the octaploid triticale (AABBDDRR) is synthesized for the first time in China. At the end of the last 70 th century, the university of mannich topba canada crossed a diploid rye with a tetraploid branched wheat t.turgidum l. (chromosome configuration AABB), and the hybrid embryos were subjected to embryo culture to synthesize hexaploid triticale (AABBRR). The prior domestic hexaploid triticale is secondary hexaploid triticale bred by crossing hexaploid triticale bred in Canada and octaploid triticale bred in China, and is used for producing high-quality forage grass and silage due to strong hybrid vigor, high plant size and genetic stability. Because triticale is a new species created by human beings, wild-type kindred species do not exist in nature, so that the genetic resource of the triticale is deficient, the genetic basis of the existing population is extremely narrow, and the genetic improvement of the triticale is extremely unfavorable. In the early stage of breeding work, breeders are expected to have a great prospect on the utilization prospect of the octaploid triticale, and expect to use the hybridization of common wheat and triticale to carry out genetic improvement so as to culture a new variety of the octaploid triticale for grains meeting production requirements. In the time of 30-40 years, people are put into the breeding work of the octaploid triticale, but due to intergeneric hybridization and poor chromosome group coordination and inclusion, the octaploid triticale is poor in genetic stability, the number of chromosomes fluctuates between 54-57, and aneuploidy often occurs, double-insemination disorder is caused, the fertility of plants is low, the ear setting rate is about 84%, the seeds are not full, and the octaploid triticale variety with production value superior to common wheat is not bred up to now.

The difficulty of distant hybridization and genetic improvement of the allopolyploid crops is as follows: firstly, because of genetic isolation of species or poor inclusion of reproductive system, the hybrid is incompatible, the double fertilization can not be completed, and viable seeds can not be formed; ② the first generation of the hybrid is usually a heterogenous double haploid, which causes sterility of the hybrid and can not be self-bred to fruit and continue the progeny. The two points seriously restrict the genetic evolution progress and the improvement effect of the triticale.

Disclosure of Invention

The invention aims to solve the problem of difficulty in surmounting hybrid F in distant hybridization₀Low viability, hybrid F₁Male sterility of generation plants, self-sterility, poor genetic stability of progeny and the like.

In order to achieve the technical purpose, the invention is specifically realized by the following technical scheme:

a breeding method of allopolyploid triticale germplasm is characterized in that diploid rye with a chromosome configuration of RR is treated by colchicine to obtain chromosome RRRR type tetraploid rye, and the chromosome RRRR type tetraploid rye is taken as a male parent and chromosome AABB type tetraploid durum is taken as a female parent for hybridization to obtain the polyploid triticale germplasm resource.

Further, the RR-type diploid rye is preferably b e pr х h rab ч b.

Further, the RRRR type tetraploid rye is preferably rye ZS 507.

Further, the chromosome AABB type tetraploid durum wheat is preferably tetraploid durum wheat di a (t.durum Desf.), tetraploid durum wheat m a.

Further, the said tetraploid durum wheat di ei a hybridizes with tetraploid rye ZS507 to obtain AABBRRRR type octaploid triticale.

Further, a tetra-ploid durum mAl zaaka zala hybridizes with rye ZS507 to obtain F₀Generation of seed, F₀Sowing the seeds in field, and sowing the seeds in the field to obtain hybrid chromosome ABRR type F₁Plants, and AABBRR type hexaploid triticale pollen is awarded to obtain AABBRR type hexaploid triticale and AARR and BBRR type tetraploid triticale; or pollen granted to AABBRRRR type octaploid triticale to obtain AABBRRRR type octaploid triticale.

Further, AABBRR type hexaploid small rye is obtained by hybridization between tetraploid durum wheat di pih and diploid rye q х h and yb ч.

The invention has the beneficial effects that:

the synthesis and genetic improvement scheme of novel hexaploid and octaploid triticale solves the problem of hybrid F which is difficult to surmount by distant hybridization₀Low viability, hybrid F₁Male sterility of generation plants, self-sterility, poor genetic stability of progeny and the like. Especially, discovery and application of hard wheat di, which has a special function of spontaneously inducing doubling of fertilized egg chromosome, greatly simplifies the steps and procedures for synthesizing allopolyploid triticale, and can be widely applied to synthesis of polyploid wheat crops and genetic improvement of varieties, so that synthesis of polyploid wheat crops and introduction of genes with excellent outer edges (disease resistance, dwarf, stress resistance and the like) are no longer inaccessible. Through the scheme, the created new polyploid triticale germplasm combines the characteristics of short stalk, high yield and hard property of wheat and the characteristics of three rust resistance and powdery mildew resistance of rye, lays a material foundation for cultivating the macaroni triticale variety, and expands the utilization space of the triticale.

Drawings

FIG. 1 is a schematic technical route of the breeding method of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, the present invention provides a method of breeding an allopolyploid triticale germplasm.

1) Diploid rye (RR) is treated with colchicine, and chromosome doubling is carried out to obtain tetraploid rye ZS507 (chromosome configuration is RRRR, 2n is 28). Treating diploid rye (RR) with colchicine to obtain tetraploid rye (RRRR), increasing the number of diploid rye chromosome set to tetraploid in order to make the number of chromosome sets of parents (from two species) equal when crossing with tetraploid durum wheat,thus, the hybrid plant can complete double fertilization to obtain viable hybrid seed F₀。

2) The evolution level of tetraploid durum wheat is higher than that of rye, the A and B chromosome sets contained in the tetraploid durum wheat undergo a long-term natural evolution process, the compatibility of the A and B chromosome sets is high, the compatibility is strong, and the ear, spikelet, floret and other flower organs of durum wheat are well developed, and convenient for ear trimming and emasculation, so that the tetraploid durum wheat is used as a female parent for accepting pollen; rye has relatively low evolution degree, poor chromosome inclusion, high plant, soft stem, narrow ear, compact growth of flower organs such as spikelet and floret, and is inconvenient for spike trimming and emasculation, but the rye has large pollen amount and long flowering period, and is convenient for pollen collection, so the rye is used as a male parent.

A diploid new-type octaploid small rye DZ line (AABBRRRR) is directly synthesized by hybridizing a tetraploid durum wheat di (T.durum Desf., AABB) as female parent with a tetraploid rye (RRRR) variety ZS 507.

Utilizing tetraploid durum wheat di xi a (T.durum Desf., chromosome configuration AABB) as female parent to hybridize with diploid rye (RR) variety V e chi х H ч c lb b a, directly synthesizing diploid new hexaploid small rye D B system (AABBRR). A diploid new octaploid triticale DZ line (AABBRRRR) is directly synthesized by hybridizing a tetraploid durum wheat di (T.durum Desf., AABB) as female parent with a tetraploid rye (RRRR) variety. These two phenomena are a special case, when the mother precursor is hard wheat di, it is found that the hybrid generation F, whether it hybridizes with tetraploid rye or diploid rye, is F₀All yielded filled, viable seeds, and F thereof₁The generation plants show 100% male fertility and can be selfed and fructified. Research shows that the durum wheat variety II can induce natural doubling of distant hybrid fertilized egg to form natural amphidiploid small rye plant. This property completely solves the distant hybrid F₁The generation plant is sterile, and the stability of the genotype is enhanced.

3) A tetraploid durum wheat Al Gamma (T.durum Desf.; chromosome configuration AABB) as female parent is hybridized with tetraploid rye variety ZS507(RRRR)To obtain F₀And (5) seed generation. F₀Dibbling the seeds to field to obtain hybrid F₁(ABRR) plant, F₁Male sterility of the plant, and pollinating pollen of DB series hexaploid triticale or DZ series octaploid triticale to obtain fertile compound cross seeds, and selfing and purifying the fertile plant to obtain the novel recombinant tetraploid, hexaploid or octaploid triticale MZ series.

F obtained by distant hybridization₀Planting seeds in the field, and growing F₁The generation plant is generally a haploid plant which is male sterile before being doubled by colchicine treatment and can not be self-bred to fruit, so the conventional method is to treat (root soaking) two ten-thousand colchicine solution in the seedling stage, and after the haploid plant absorbs the colchicine solution, a growing point chromosome is doubled to become a diploid plant, and the diploid plant can bloom and fruit. The application directly grants pollen of hexaploid or octaploid triticale fertile plants to haploid hybrid plants, and fructification can be carried out to obtain recombinants (plants). Selfing and purifying the recombinant (plant) to obtain the recombinant tetraploid, hexaploid or octaploid triticale line. Double crossing F₁After the seeds on the plant are identified by root tip cytology, the next generation is dibbled in the field, self-bred and feasible, and purified and selected, so that the homozygous type-MZ series of tetraploid, hexaploid or octaploid triticale containing target characters can be obtained.

Distant hybrid contemporary (F)₀Generation) seeds are very shrunken and non-viable, mainly because the double fertilized crops exist in the seed plants, namely, after pollination, pollen grains of a donor germinate on the stigma of a receptor, pollen tubes enter the nucellus through the nucellus and finally enter the embryo sac to eject 2 sperm cells, one sperm cell is combined with an egg cell to form a fertilized egg, and the other sperm cell is combined with a central cell (containing 2 polar nuclei which are haploids) to form a primary endosperm nucleus. The same species can form viable seeds because the number of the chromosome group and the chromosome is equal, and the double fertilization process has no obstacle. While distant hybridization between different species cannot be completed due to the mismatch of the number of the chromosome sets, especially the matching degree of the central cell (containing 2 polar nuclei) to the chromosome set of the donor sperm cell is strict if the chromosome setIf the number of the seed is not matched, a primary endosperm nucleus cannot be formed, starch cannot be accumulated, and thus, a viable seed is formed. The tetraploid durum wheat is crossed with tetraploid rye to ensure equal chromosome group number and produce viable seed after crossing.

Distant hybridization F₁The generation plant is a double haploid plant composed of heterologous species, and the hybrid is male sterile and generally cannot fruit without manual intervention. Hybrid F is given pollen from a fertile hexaploid or octaploid triticale plant₁When the sterile plants are pollinated, because the chromosome groups of the parents of the male parent and the female parent are homologous and the number of the chromosomes is equal, the two parties can easily complete the double fertilization effect, and healthy seeds are produced. The complex work of artificial doubling of haploid plants treated by colchicine solution is saved, and the efficiency of hybridization improvement is improved.

A durum wheat material i xi naturally induces doubling of fertilized egg chromosome to produce diploid zygote. Alpha, and tetraploid rye or diploid rye, capable of inducing hybrid to perform chromosome doubling in embryonic stage to form diploid seed, thus ensuring hybrid viability and F₁The generation plant becomes a male fertile plant, further improving the efficiency of synthesizing the octaploid and the hexaploid triticale by distant hybridization and increasing the genetic stability of the novel allopolyploid.

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