Polyploid two-line hybrid rice and breeding method thereof

Abstract

A method for breeding polyploid two-line hybrid rice includes determining a tetraploid rice photo thermosensitive genic male sterile line with the gene characteristic of PMeS (polyploid meiosis stability) and a tetraploid rice restoring line with the gene characteristic of PMeS; hybridizing and matching by indica sterile/japonica restoring or japonica sterile/indica restoring hybrid combination; preparing a tetraploid rice hybrid by adopting a tetraploid rice photo thermosensitive genic male sterile line and a tetraploid rice restoring line; and breeding a stable tetraploid rice hybrid combination which is determined as the polyploid two-line hybrid rice combination. The breeding method disclosed by the present invention utilizes the strong heterosis of polyploid rice, and transforms the existing diploid heterosis into the heterosis of polyploid two-line hybrid rice; and by adopting the method disclosed by the present invention, a new polyploid two-line hybrid rice variety with large ears, large grains and high yield can be bred.

Claims

1. A breeding method for producing a polyploid two-line hybrid rice, comprising: (a) providing the tetraploid rice photo thermosensitive genic male sterile line PS001 having polyploid meiosis stability (PMeS) gene and the tetraploid rice two-line restoring line PR005 having the PMeS gene, wherein PS001 is an indica sterile line, sample of seed of said line is deposited under CCTCC No: P202008; and wherein PR005 is a japonica restoring line, sample of seed of said line is deposited under CCTCC No: P202009; (b) hybridizing plants of the tetraploid rice photo thermosensitive genic male sterile line PS001 with plants of the tetraploid rice two-line restoring line to obtain tetraploid two-line rice hybrid seed; (c) growing the tetraploid two-line rice hybrid seed to produce tetraploid two-line rice hybrid plants; and (d) selecting one or more of the tetraploid rice hybrid plants having a setting percentage of over 80%, and a yield increase of more than 4% than that of the tetraploid rice two-line restoring line PR005 and the control diploid hybrid rice plant of line Fengliangyou No: 4, wherein the selected one or more tetraploid rice hybrid plants are determined as tetraploid two-line hybrid rice plants.

2. A tetraploid two-line hybrid rice plant, 2n=4X=48, obtained by the breeding method according to claim 1, wherein the plant has a setting percentage of more than 80%, and is named as PH015, a representative sample of seed of said plant is deposited under CCTCC No: P202005.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings illustrate one or more embodiments of the invention and, together with the written description, serve to explain the principles of the invention. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like elements of an embodiment.

(2) FIG. 1 is the picture of real products of the tetraploid two-line hybrid rice PH015 and parents thereof of embodiment 1, wherein the left is PS001 tetraploid rice two-line sterile line (female parent); the middle is the tetraploid two-line hybrid rice PH015; and the right is PR005 tetraploid rice two-line restoring line (male parent).

(3) FIG. 2 is the picture of real products of the tetraploid two-line hybrid rice PH083 and parents thereof of embodiment 2, wherein the left is the PS002 tetraploid rice two-line sterile line (female parent); the middle is the tetraploid two-line hybrid rice PH083; and the right is the PR027 tetraploid rice two-line restoring line (male parent).

(4) FIG. 3 is the picture of real products of the tetraploid two-line hybrid rice PH107 and parents thereof of embodiment 3, wherein the left is the PS003 tetraploid rice two-line sterile line (female parent); the middle is the tetraploid two-line hybrid rice PH107; and the right is the PR076 tetraploid rice two-line restoring line (male parent).

(5) FIG. 4 is the picture of the seed production field of the tetraploid two-line hybrid rice, wherein the relatively short plants in the middle are the PS001 tetraploid rice photo thermosensitive genic male sterile line (female parent); and the relatively high plants in two sides are the PR005 tetraploid rice two-line restoring line (male parent).

(6) FIGS. 5A-5C show a PS001-PS010 family tree, a PS011-PS045 family tree, and a PS046-PS068 family tree, respectively.

(7) FIGS. 6A-6D show a PR001-PR036 family tree, a PR037-PR060 family tree, a PR061-PR079 family tree, and a PR061-PR079 family tree, respectively.

DETAILED DESCRIPTION OF THE INVENTION

(8) The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean one and only one unless specifically so stated, but rather one or more. The word exemplary is used herein to mean serving as an example, instance, or illustration. Any aspect described herein as exemplary is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term some refers to one or more. Combinations such as at least one of A, B, or C, one or more of A, B, or C, at least one of A, B, and C, one or more of A, B, and C, and A, B, C, or any combination thereof include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as at least one of A, B, or C, one or more of A, B, or C, at least one of A, B, and C, one or more of A, B, and C, and A, B, C, or any combination thereof may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words module, mechanism, element, device and the like may not be a substitute for the word means. As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase means for. It should also be understood that one or more steps within a method may be executed in different order (or concurrently) without altering the principles of the invention.

(9) The terms used in this specification generally have their ordinary meanings in the art, within the context of the invention, and in the specific context where each term is used. Certain terms that are used to describe the invention are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner regarding the description of the invention. For convenience, certain terms may be highlighted, for example using italics and/or quotation marks. The use of highlighting has no influence on the scope and meaning of a term; the scope and meaning of a term are the same, in the same context, whether or not it is highlighted. It will be appreciated that the same thing can be said in more thin one way. Consequently, alternative language and synonyms may be used for any one or more of the terms discussed herein, nor is any special significance to be placed upon whether or not a term is elaborated or discussed herein. Synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and in no way limits the scope and meaning of the invention or of any exemplified term. Likewise, the invention is not limited to various embodiments given in this specification.

(10) It will be understood that when an element is referred to as being on, attached to, connected to, coupled with, contacting, etc., another element, it can be directly on, attached to, connected to, coupled with or contacting the other element or intervening elements may also be present. In contrast, when an element is referred to as being, for example, directly on, directly attached to, directly connected to, directly coupled with or directly contacting another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed adjacent to another feature may have portions that overlap or underlie the adjacent feature.

(11) The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms a, an and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms comprises and/or comprising, or includes and/or including or has and/or having when used in this specification specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

(12) It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below can be termed a second element, component, region, layer or section without departing from the teachings of the disclosure.

(13) Furthermore, relative terms, such as lower or bottom and upper or top, may be used herein to describe one element's relationship to another element as illustrated in the figures. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation shown in the figures. For example, if the device in one of the figures is turned over, elements described as being on the lower side of other elements would then be oriented on the upper sides of the other elements. The exemplary term lower can, therefore, encompass both an orientation of lower and upper, depending on the particular orientation of the figure. Similarly, if the device in one of the figures is turned over, elements described as below or beneath other elements would then be oriented above the other elements. The exemplary terms below or beneath can, therefore, encompass both an orientation of above and below.

(14) Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

(15) As used herein, the terms comprise or comprising, include or including, carry or carrying, has/have or having, contain or containing, involve or involving and the like are to be understood to be open-ended, i.e., to mean including but not limited to.

(16) Typically, terms such as about, approximately, generally, substantially, and the like unless otherwise indicated mean within 20 percent, preferably within 10 percent, preferably within 5 percent, and even more preferably within 3 percent of a given value or range. Numerical quantities given herein are approximate, meaning that the term about, approximately, generally, or substantially can be inferred if not expressly stated.

(17) The description is now made as to the embodiments of the invention in conjunction with the accompanying drawings. It should be understood that specific embodiments described herein are merely intended to explain the invention, but not intended to limit the invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects.

Embodiment 1 the Breeding Process of the Tetraploid Two-Line Hybrid Rice PH015

(18) (a) Determining a tetraploid rice photo (thermo) sensitive genic male sterile line with the gene characteristic of PMeS and a tetraploid rice two-line restoring line with the gene characteristic of PMeS; and adopting the tetraploid rice genic male sterile line PS001 containing PMeS genes as the sterile line for preparing a two-line tetraploid hybrid combination and the tetraploid rice two-line restoring line PR005 containing PMeS genes as the restoring line of the tetraploid two-line hybrid rice;

(19) (b) determining that the hybrid combination manner of indica sterile/japonica restoring is used for hybridizing and matching the indica sterile line PS001 and the japonica restoring line PR005;

(20) (c) performing heterosis detection on the PS001 tetraploid rice two-line sterile line in the aspects of growth period, morphological characters, flowering habit, sterile and transformation characteristics, heterogamety and preparation combination;

(21) (d) performing heterosis detection analysis on the PR005 tetraploid two-line restoring line in the aspects of growth period, morphological characteristics, flowering habit, anther characteristics, heterogamety and preparation combination;

(22) (e) preparing tetraploid rice hybrids by adopting the PS001 tetraploid rice two-line sterile line and the PR005 tetraploid two-line restoring line;

(23) (f) performing line comparison on the prepared tetraploid rice hybrids, and comparing with the tetraploid rice two-line restoring line and control diploid hybrid from the aspects of growth period, morphological characteristics, resistance and flowering habit and setting percentage;

(24) (g) breeding the combination hybrid of PS001PR005, which is specifically shown as a uniform stable tetraploid rice hybrid with excellent morphological characteristics, appropriate growth period (sown in appropriate reason in Wuhan, with the total growth period of 135-138 days), relatively strong resistance, setting percentages of more than 80%, and yield increase of more than 5.2% than the tetraploid rice restoring lines and the control diploid hybrid, and determining as the tetraploid two-line hybrid rice, named as PH015.

(25) As shown in FIG. 1, FIG. 1 is the picture of real products of the tetraploid two-line hybrid rice PH015 and parents thereof of the present embodiment, wherein the left is PS001 tetraploid rice two-line sterile line (female parent); the middle is the tetraploid two-line hybrid rice PH015; and the right is PR005 tetraploid rice two-line restoring line (male parent). It can be seen from the drawing: compared with the parents, hybrid PH015 shows better growth vigour and tillering ability and has longer rice ears and more ear grains, indicating that the tetraploid two-line hubrid rice has strong heterosis.

(26) As shown in FIG. 4, FIG. 4 is the picture of real products of field seed production of the tetraploid two-line hybrid rice PH015 of the present embodiment, wherein the relatively short plants in the middle are the PS001: tetraploid rice photo thermosensitive genic male sterile line (female parent); and the relatively high plants in two sides are the PR005: tetraploid rice two-line restoring line (male parent). It can be seen from the drawing: the flowering phase of the parents can meet each other, and natural outcrossing setting is good, indicating that the tetraploid two-line hybrid rice can well realize large field seed production, and a large quantity of hybrids can be harvested, thus being beneficial to large-area production and application.

Embodiment 2 the Breeding Process of the Tetraploid Two-Line Hybrid Rice PH083

(27) (a) Determining a tetraploid rice photo (thermo) sensitive genic male sterile line with the gene characteristic of PMeS and a tetraploid rice two-line restoring line with the gene characteristic of PMeS; and adopting the tetraploid rice genic male sterile line PS002 containing PMeS genes as the sterile line for preparing a two-line tetraploid hybrid combination and the tetraploid rice two-line restoring line PR027 containing PMeS genes as the restoring line of the tetraploid two-line hybrid rice;

(28) (b) determining that the hybrid combination manner of indica sterile/japonica restoring is used for hybridizing and matching the indica sterile line PS002 and the japonica restoring line PR027;

(29) (c) performing heterosis detection on the PS002 tetraploid rice two-line sterile line in the aspects of growth period, morphological characters, flowering habit, sterile and transformation characteristics, heterogamety and preparation combination;

(30) (d) performing heterosis detection analysis on the PR027 tetraploid two-line restoring line in the aspects of growth period, morphological characteristics, flowering habit, anther characteristics, heterogamety and preparation combination;

(31) (e) preparing tetraploid rice hybrids by adopting the PS002 tetraploid rice two-line sterile line and the PR027 tetraploid two-line restoring line;

(32) (f) performing line comparison on the prepared tetraploid rice hybrids, and comparing with the tetraploid rice restoring line and control diploid hybrid from the aspects of growth period, morphological characteristics, resistance and flowering habit and setting percentage;

(33) (g) breeding the combination hybrid of PS002PR027, which is specifically shown as a uniform stable tetraploid combination hybrid with excellent morphological characteristics, appropriate growth period (sown in appropriate reason in Wuhan, with the total growth period of 133-136 days), relatively strong resistance, setting percentages of more than 86%, and yield increase of more than 6.8% than the tetraploid rice restoring lines and the control diploid hybrid, and determining as the tetraploid two-line hybrid rice, named as PH083.

(34) As shown in FIG. 2, FIG. 2 is the picture of real products of the tetraploid two-line hybrid rice PH083 and parents thereof of the present embodiment, wherein the left is the PS002 tetraploid rice two-line sterile line (female parent); the middle is the tetraploid two-line hybrid rice PH083; and the right is the PR027 tetraploid rice two-line restoring line (male parent). It can be seen from the figure: compared with the parents, hybrid PH083 has better growth vigour and more tillering, and the ear length, grain number per ear and thousand seed weight are all prior to those of the parents, indicating that the tetraploid two-line hybrid rice has strong heterosis.

Embodiment 3 the Breeding Process of the Tetraploid Two-Line Hybrid Rice PH107

(35) (a) Determining a tetraploid rice photo (thermo) sensitive genic male sterile line with the gene characteristic of PMeS and a tetraploid rice two-line restoring line with the gene characteristic of PMeS; and adopting the tetraploid rice genic male sterile line PS003 containing PMeS genes as the sterile line for preparing a two-line tetraploid hybrid combination and the tetraploid rice two-line restoring line PR076 containing PMeS genes as the restoring line of the tetraploid two-line hybrid rice;

(36) (b) determining that the hybrid combination manner of indica sterile/japonica restoring is used for hybridizing and matching the indica sterile line PS003 and the japonica restoring line PR076;

(37) (c) performing heterosis detection on the PS003 tetraploid rice two-line sterile line in the aspects of growth period, morphological characters, flowering habit, sterile and transformation characteristics, heterogamety and preparation combination;

(38) (d) performing heterosis detection analysis on the PR076 tetraploid two-line restoring line in the aspects of growth period, morphological characteristics, flowering habit, anther characteristics, heterogamety and preparation combination;

(39) (e) preparing tetraploid rice hybrids by adopting the PS003 tetraploid rice two-line sterile line and the PR076 two-line restoring line;

(40) (f) performing line comparison on the prepared tetraploid rice hybrid, and comparing with the tetraploid rice restoring line and control diploid hybrid from the aspects of growth period, morphological characteristics, resistance and flowering habit and setting percentage;

(41) (g) breeding the combination hybrid of PS003PR076, which is specifically shown as a uniform stable tetraploid combination hybrid with excellent morphological characteristics, appropriate growth period (sown in appropriate reason in Wuhan, with the total growth period of 134-136 days), relatively strong resistance, setting percentages of more than 84%, and yield increase of more than 4.8% than the tetraploid rice restoring lines and the control diploid hybrid, and determining as the tetraploid two-line hybrid rice, named as PH107.

(42) As shown in FIG. 3, FIG. 3 is the picture of real products of the tetraploid two-line hybrid rice PH107 and parents thereof of present embodiment, wherein the left is the PS003 tetraploid rice two-line sterile line (female parent); the middle is the tetraploid two-line hybrid rice PH107; and the right is the PR076 tetraploid rice two-line restoring line (male parent). It can be seen from the figure: compared with the parents, hybrid PH107 has better growth vigour and more tillering, and the ear length, grain number ear and setting percentage are all prior to those of the parents, indicating that the tetraploid two-line hybrid rice has strong heterosis.

(43) The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching.

(44) The embodiments are chosen and described in order to explain the principles of the disclosure and their practical application so as to activate others skilled in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present disclosure pertains without departing from its spirit and scope. Accordingly, the scope of the present disclosure is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.