MOLECULAR MARKERS FOR IDENTIFICATION OF DISEASE RESISTANCE AND/OR AGRONOMIC TRAITS IN STRAWBERRY PLANTS AND USES THEREOF
20220349016 · 2022-11-03
Assignee
Inventors
Cpc classification
A01H1/04
HUMAN NECESSITIES
International classification
A01H1/04
HUMAN NECESSITIES
Abstract
The invention relates to single nucleotide polymorphism (SNP) markers that provide improved resistance to one or more diseases and/or improved agronomic traits, such as improved resistance to Fusarium infection, improved resistance to Macrophomina infection, improved resistance to Colletotrichum resistance, improved remontancy and/or improved berry weight. Also described are compositions and methods of using the SNP markers in selecting, obtaining, or developing strawberry plants or varieties with the given improved traits.
Claims
1. (canceled)
2. A method for selecting a strawberry plant with improved resistance to Fusarium infection, the method comprising: a. crossing two parental strawberry plants to produce a plurality of progeny seed; b. growing said progeny seed to produce a population of progeny plants; c. obtaining a nucleic acid sample from one or more individuals within said population of progeny plants; d. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the two or more Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:1-7; and e. selecting a strawberry plant from said population of progeny plants based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample.
3. A method for obtaining a strawberry plant with improved resistance to Fusarium infection, the method comprising: a. providing an initial population of strawberry plants; b. obtaining a nucleic acid sample from one or more individuals within said initial population; c. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the two or more Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) loci within SEQ ID NOs:1-7; d. selecting a strawberry plant from said initial population based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample; and e. crossing the selected strawberry plant with a second strawberry plant to produce progeny plants comprising improved resistance to disease caused by Fusarium infection.
4. The method of claim 3, wherein two strawberry plants are selected from said initial population based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample for each of the two selected plants, and wherein the two selected plants are crossed with one another to produce progeny plants comprising improved resistance to disease caused by Fusarium infection.
5. The method of claim 3, wherein the selected strawberry plant is homozygous for at least one of the two or more Fusarium resistance alleles.
6. (canceled)
7. The method of claim 3, wherein the detection step comprises detecting three, four, five, or six of the SNP loci within SEQ ID NOs:1-7.
8. The method of claim 3, wherein the detection step further comprises detecting i) at least one allele conferring improved resistance to disease caused by Macrophomina infection (“Macrophomina resistance allele”), wherein each of the at least one Macrophomina resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) loci within SEQ ID NOs:8 and 9; ii) an allele conferring improved resistance to disease caused by Colletotrichum infection (“Colletotrichum resistance allele”), wherein the Colletotrichum resistance allele is an allele of the SNP locus within SEQ ID NO:10; iii) at least one Macrophomina resistance allele of i) and the Colletotrichum resistance allele of ii); or iv) both Macrophomina resistance alleles of i) and the Colletotrichum resistance allele of ii).
9. The method of claim 3, wherein the detection step further comprises detecting the presence or absence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11.
10. (canceled)
11. A method for selecting a strawberry plant with improved resistance to Macrophomina and/or Colletotrichum infection, the method comprising: a. crossing two parental strawberry plants to produce a plurality of progeny seed; b. growing said progeny seed to produce a population of progeny plants; c. obtaining a nucleic acid sample from one or more individuals within said population of progeny plants; d. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Macrophomina and/or Colletotrichum infection (“Macrophomina/Colletotrichum resistance allele”), wherein each of the two or more Macrophomina/Colletotrichum resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:8-10; and e. selecting a strawberry plant from said population of progeny plants based on the presence of the two or more Macrophomina/Colletotrichum resistance alleles in the nucleic acid sample.
12. A method for obtaining a strawberry plant with improved resistance to Macrophomina or Colletotrichum infection, the method comprising: a. providing an initial population of strawberry plants; b. obtaining a nucleic acid sample from one or more individuals within said initial population; c. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Macrophomina and/or Colletotrichum infection (“Macrophomina/Colletotrichum resistance allele”), wherein each of the two or more Macrophomina/Colletotrichum resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:8-10; d. selecting a strawberry plant from said initial population based on the presence of the two or more Macrophomina/Colletotrichum resistance alleles in the nucleic acid sample; and e. crossing the selected strawberry plant with a second strawberry plant to produce progeny plants comprising improved resistance to disease caused by Macrophomina or Colletotrichum infection.
13. The method of claim 12, wherein two strawberry plants are selected from said initial population based on the presence of the two or more Macrophomina/Colletotrichum resistance alleles in the nucleic acid sample for each of the two selected plants, and wherein the two selected plants are crossed with one another to produce progeny plants comprising improved resistance to disease caused by Macrophomina or Colletotrichum infection.
14. The method of claim 12, wherein the selected strawberry plant is homozygous for at least one of the two or more Macrophomina/Colletotrichum resistance alleles.
15. (canceled)
16. The method of claim 12, wherein the detection step comprises detecting three of the SNP loci within SEQ ID NOs:8-10.
17. The method of claim 12, wherein the detection step further comprises detecting at least one allele conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the at least one Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) loci within SEQ ID NOs:1-7.
18. The method of claim 17, wherein the method comprises detecting two, three, four, five, or six Fusarium resistance alleles of SEQ ID NOs:1-7.
19. The method of claim 12, wherein the detection step further comprises detecting the presence or absence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11.
20.-21. (canceled)
22. A method for obtaining a strawberry plant with improved agronomic traits, the method comprising: a. providing an initial population of strawberry plants; b. obtaining a nucleic acid sample from one or more individuals within said initial population; c. detecting in each of said nucleic acid samples the presence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11; d. selecting a strawberry plant from said population of progeny plants based on the presence of the at remontancy allele in the nucleic acid samples; and e. crossing the selected strawberry plant with a second strawberry plant to produce progeny plants comprising improved agronomic traits.
23. The method of claim 22, wherein two strawberry plants are selected from said initial population based on the presence of the selected allele in the nucleic acid sample for each of the two selected plants, and wherein the two selected plants are crossed with one another to produce progeny plants comprising improved agronomic traits.
24. The method of claim 22, wherein the detection step further comprises detecting in each of said nucleic acid samples the presence or absence of at least one allele conferring increased berry weight (“berry weight allele”), wherein the at least one berry weight allele is an allele of at least one SNP loci within SEQ ID NOs:12-17.
25. The method of claim 24, wherein the detection step comprises detecting at least two, three, four, five, or six berry weight alleles of SEQ ID NOs:12-17.
26.-27. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The foregoing summary, as well as the following detailed description of preferred embodiments of the present application, will be better understood when read in conjunction with the appended drawings. It should be understood, however, that the application is not limited to the precise embodiments shown in the drawings.
[0019]
[0020]
[0021]
[0022]
[0023]
[0024]
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0026] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention pertains. Otherwise, certain terms used herein have the meanings as set forth in the specification.
[0027] It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural reference unless the context clearly dictates otherwise.
[0028] Unless otherwise stated, any numerical values, such as a concentration or a concentration range described herein, are to be understood as being modified in all instances by the term “about.” Thus, a numerical value typically includes ±10% of the recited value. As used herein, the use of a numerical range expressly includes all possible subranges, all individual numerical values within that range, including integers within such ranges and fractions of the values unless the context clearly indicates otherwise.
[0029] Unless otherwise indicated, the term “at least” preceding a series of elements is to be understood to refer to every element in the series. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the invention.
[0030] As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having,” “contains” or “containing,” or any other variation thereof, will be understood to imply the inclusion of a stated item or group of items but not the exclusion of any other item or group of items and are intended to be non-exclusive or open-ended. For example, a composition, a mixture, a process, a method, an article, or an apparatus that comprises a list of elements is not necessarily limited to only those elements but can include other elements not expressly listed or inherent to such composition, mixture, process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
[0031] It should also be understood that the terms “about,” “approximately,” “generally,” “substantially” and like terms, used herein when referring to a dimension or characteristic of a component of the preferred invention, indicate that the described dimension/characteristic is not a strict boundary or parameter and does not exclude minor variations therefrom that are functionally the same or similar, as would be understood by one having ordinary skill in the art. At a minimum, such references that include a numerical parameter would include variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.
[0032] The term “molecular marker” or “marker” as used herein refers generally to a molecule, including a gene, protein, carbohydrate structure, or glycolipid, the expression of which in or on a mammalian tissue or cell or secreted can be detected by known methods (or methods disclosed herein) and is predictive or can be used to predict (or aid prediction) the presence or absence of a trait, such as improved resistance to certain pathogens or diseases or agronomic characteristics.
[0033] A “single nucleotide polymorphism”, or “SNP”, refers to a single base position in an RNA or DNA molecule (e.g., a polynucleotide), at which different alleles, or alternative nucleotides, exist in a population. The SNP position (interchangeably referred to herein as SNP, SNP site, SNP locus) is usually preceded by and followed by conserved sequences of the allele (e.g., sequences that vary in less than 1/100 or 1/1000 members of the populations). An individual can be homozygous or heterozygous for an allele at each SNP position.
Molecular Markers for Identification of Certain Disease Resistance and/or Agronomic Traits in Strawberry Plants
Fusarium Resistance Markers for Strawberry Plants
[0034] Fusarium resistance markers for strawberry plants are identified as one or more of the following SNPs shown in Table 1. The underlined base in the corresponding sequence indicates the polymorphism of the SNP.
TABLE-US-00001 TABLE 1 SNP Locus Sequence PSI-D1 TGATTGTCTGAGAA (SEQ ID NO: 1) PSI-D2 TGAAGTATGAATTAA (SEQ ID NO: 2) PSI-D3 AAGGGCCATGTG (SEQ ID NO: 3) PSI-D4 CACCGCCTGGTT (SEQ ID NO: 4) PSI-D5 AACCATCCACAA (SEQ ID NO: 5) PSI-D6 TGGCCTCCGAG (SEQ ID NO: 6) PSI-D7 CAGCTTTGGAAT (SEQ ID NO: 7)
Macrophomina Resistance Markers for Strawberry Plants
[0035] Macrophomina resistance markers for strawberry plants are identified as one or more of the following SNPs shown in Table 2. The underlined base in the corresponding sequence indicates the polymorphism of the SNP.
TABLE-US-00002 TABLE 2 SNP Locus Sequence PSI-D11 ATGCATAAGATGTG (SEQ ID NO: 8) PSI-D12 ACTGTAACGACA (SEQ ID NO: 9)
Colletotrichum Resistance Marker for Strawberry Plants
[0036] Colletotrichum resistance marker for strawberry plants is identified as the following SNP shown in Table 3. The underlined base in the corresponding sequence indicates the polymorphism of the SNP.
TABLE-US-00003 TABLE 3 SNP Locus Sequence PSI-D8 AGATAGCTAAACTCA (SEQ ID NO: 10)
Remontancy Marker for Strawberry Plants
[0037] The remontancy marker for strawberry plants is identified as the following SNP shown in Table 4, wherein the remontancy allele is a heterozygous state of the following SNP. The bracketed bases in the corresponding sequence indicate the polymorphism of the SNP.
TABLE-US-00004 TABLE 4 SNP Locus Sequence PSI-ROM 1 GGATC[G/T]GTGAAG (SEQ ID NO: 11)
Improved Berry Weight Marker for Strawberry Plants
[0038] Improved berry weight markers for strawberry plants are identified as one or more of the following SNPs shown in Table 5. The underlined base in the corresponding sequence indicates the polymorphism of the SNP.
TABLE-US-00005 TABLE 5 SNP Locus Sequence PSI-BW1 CTCGCCGTTCTA (SEQ ID NO: 12) PSI-BW2 GATCYACATTCT (SEQ ID NO: 13) PSI-BW3 ATCCTTATCRAC (SEQ ID NO: 14) PSI-BW4 TGGTGGTTGTTC (SEQ ID NO: 15) PSI-BW5 GCCACGAAATGA (SEQ ID NO: 16) PSI-BW6 AAGCATCATCAA (SEQ ID NO: 17)
Exemplified Embodiments
[0039] Embodiment 1. A method for selecting a strawberry plant with improved resistance to Fusarium infection, the method comprising: [0040] a. providing an initial population of strawberry plants; [0041] b. obtaining a nucleic acid sample from one or more individuals within said initial population; [0042] c. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the two or more Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:1-7; and [0043] d. selecting a strawberry plant from said initial population based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample.
[0044] Embodiment 2. A method for selecting a strawberry plant with improved resistance to Fusarium infection, the method comprising: [0045] a. crossing two parental strawberry plants to produce a plurality of progeny seed; [0046] b. growing said progeny seed to produce a population of progeny plants; [0047] c. obtaining a nucleic acid sample from one or more individuals within said population of progeny plants; [0048] d. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the two or more Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:1-7; and [0049] e. selecting a strawberry plant from said population of progeny plants based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample.
[0050] Embodiment 3. A method for obtaining a strawberry plant with improved resistance to Fusarium infection, the method comprising: [0051] a. providing an initial population of strawberry plants; [0052] b. obtaining a nucleic acid sample from one or more individuals within said initial population; [0053] c. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the two or more Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) loci within SEQ ID NOs:1-7; [0054] d. selecting a strawberry plant from said initial population based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample; and [0055] e. crossing the selected strawberry plant with a second strawberry plant to produce progeny plants comprising improved resistance to disease caused by Fusarium infection.
[0056] Embodiment 4. The method of embodiment 3, wherein two strawberry plants are selected from said initial population based on the presence of the two or more Fusarium resistance alleles in the nucleic acid sample for each of the two selected plants, and wherein the two selected plants are crossed with one another to produce progeny plants comprising improved resistance to disease caused by Fusarium infection.
[0057] Embodiment 5. The method of any one of embodiments 3 or 4, wherein at least one of the two strawberry plants in the cross is homozygous for at least one of the two or more Fusarium resistance alleles.
[0058] Embodiment 6. The method of any one of embodiments 3 or 4, wherein both of the two strawberry plants in the cross are homozygous for at least one of the two or more Fusarium resistance alleles.
[0059] Embodiment 7. The method of any one of embodiments 1-6, wherein the detection step comprises detecting at least three of the SNP loci within SEQ ID NOs:1-7, optionally at least four of the SNP loci within SEQ ID NOs:1-7, optionally at least five of the SNP loci within SEQ ID NOs:1-7, optionally at least six of the listed SNP loci within SEQ ID NOs:1-7, or optionally at least seven of the SNP loci within SEQ ID NOs:1-7.
[0060] Embodiment 8. The method of any one of embodiments 1-7, wherein the detection step further comprises detecting [0061] i) at least one allele conferring improved resistance to disease caused by Macrophomina infection (“Macrophomina resistance allele”), wherein each of the at least one Macrophomina resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) loci within SEQ ID NOs:8 and 9; [0062] ii) an allele conferring improved resistance to disease caused by Colletotrichum infection (“Colletotrichum resistance allele”), wherein the Colletotrichum resistance allele is an allele of the SNP locus within SEQ ID NO:10; [0063] iii) at least one Macrophomina resistance allele of i) and the Colletotrichum resistance allele of ii); or [0064] iv) both Macrophomina resistance alleles of i) and the Colletotrichum resistance allele of ii).
[0065] Embodiment 9. The method of any one of embodiments 1-8, wherein the detection step further comprises detecting the presence or absence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11.
[0066] Embodiment 10. A method for selecting a strawberry plant with improved resistance to Macrophomina and/or Colletotrichum infection, the method comprising: [0067] a. providing an initial population of strawberry plants; [0068] b. obtaining a nucleic acid sample from one or more individuals within said initial population; [0069] c. detecting in each of said nucleic acid samples the presence or absense of two or more alleles conferring improved resistance to disease caused by Macrophomina and/or Colletotrichum infection (“Macrophomina/Colletotrichum resistance allele”), wherein each of the two or more Macrophomina/Colletotrichum resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:8-10; and [0070] d. selecting a strawberry plant from said initial population based on the presence of the two or more Macrophomina/Colletotrichum resistance allelez in the nucleic acid sample.
[0071] Embodiment 11. A method for selecting a strawberry plant with improved resistance to Macrophomina and/or Colletotrichum infection, the method comprising: [0072] a. crossing two parental strawberry plants to produce a plurality of progeny seed; [0073] b. growing said progeny seed to produce a population of progeny plants; [0074] c. obtaining a nucleic acid sample from one or more individuals within said population of progeny plants; [0075] d. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Macrophomina and/or Colletotrichum infection (“Macrophomina/Colletotrichum resistance allele”), wherein each of the two or more Macrophomina/Colletotrichum resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:8-10; and [0076] e. selecting a strawberry plant from said population of progeny plants based on the presence of the two or more Macrophomina/Colletotrichum resistance alleles in the nucleic acid sample.
[0077] Embodiment 12. A method for obtaining a strawberry plant with improved resistance to Macrophomina or Colletotrichum infection, the method comprising: [0078] a. providing an initial population of strawberry plants; [0079] b. obtaining a nucleic acid sample from one or more individuals within said initial population; [0080] c. detecting in each of said nucleic acid samples the presence or absence of two or more alleles conferring improved resistance to disease caused by Macrophomina and/or Colletotrichum infection (“Macrophomina/Colletotrichum resistance allele”), wherein each of the two or more Macrophomina/Colletotrichum resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) marker selected from the SNP loci within SEQ ID NOs:8-10; [0081] d. selecting a strawberry plant from said initial population based on the presence of the two or more Macrophomina/Colletotrichum resistance alleles in the nucleic acid sample; and [0082] crossing the selected strawberry plant with a second strawberry plant to produce progeny plants comprising improved resistance to disease caused by Macrophomina or Colletotrichum infection.
[0083] Embodiment 13. The method of embodiment 12, wherein two strawberry plants are selected from said initial population based on the presence of the two or more Macrophomina/Colletotrichum resistance alleles in the nucleic acid sample for each of the two selected plants, and wherein the two selected plants are crossed with one another to produce progeny plants comprising improved resistance to disease caused by Macrophomina or Colletotrichum infection.
[0084] Embodiment 14. The method of any one of embodiment 12 or embodiment 13, wherein at least one of the two strawberry plants in the cross is homozygous for at least one of the two or more Macrophomina/Colletotrichum resistance alleles.
[0085] Embodiment 15. The method of any one of embodiment 12 or embodiment 13, wherein both of the strawberry plants in the cross are homozygous for at least one of the two or more Macrophomina/Colletotrichum resistance alleles.
[0086] Embodiment 16. The method of any one of embodiments 10-15, wherein the detection step comprises detecting three of the SNP loci within SEQ ID NOs:8-10.
[0087] Embodiment 17. The method of any one of embodiments 10-16, wherein the detection step further comprises detecting at least one allele conferring improved resistance to disease caused by Fusarium infection (“Fusarium resistance allele”), wherein each of the at least one Fusarium resistance alleles is an allele of at least one single nucleotide polymorphism (SNP) loci within SEQ ID NOs:1-7.
[0088] Embodiment 18. The method of embodiment 17, wherein the method comprises detecting two or more Fusarium resistance alleles of SEQ ID NOs:1-7, optionally three or more Fusarium resistance alleles of SEQ ID NOs:1-7, optionally four or more Fusarium resistance alleles of SEQ ID NOs:1-7, optionally five or more Fusarium resistance alleles of SEQ ID NOs:1-7, optionally six or more Fusarium resistance alleles of SEQ ID NOs:1-7, optionally seven or more Fusarium resistance alleles of SEQ ID NOs:1-7.
[0089] Embodiment 19. The method of any one of embodiment 10-18, wherein the detection step further comprises detecting the presence or absence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11.
[0090] Embodiment 20. A method for selecting a strawberry plant with improved agronomic traits, the method comprising: [0091] a. providing an initial population of strawberry plants; [0092] b. obtaining a nucleic acid sample from one or more individuals within said initial population; [0093] c. detecting in each of said nucleic acid samples the presence or absence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11; and [0094] d. selecting a strawberry plant from said initial population based on the presence of the at remontancy allele in the nucleic acid samples.
[0095] Embodiment 21. A method for selecting a strawberry plant with improved agronomic traits, the method comprising: [0096] a. crossing two parental strawberry plants to produce a plurality of progeny seed; [0097] b. growing said progeny seed to produce a population of progeny plants; [0098] c. obtaining a nucleic acid sample from one or more individuals within said population of progeny plants; [0099] d. detecting in each of said nucleic acid samples the presence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11; and [0100] e. selecting a strawberry plant from said population of progeny plants based on the presence of the at remontancy allele in the nucleic acid samples.
[0101] Embodiment 22. A method for obtaining a strawberry plant with improved agronomic traits, the method comprising: [0102] a. providing an initial population of strawberry plants; [0103] b. obtaining a nucleic acid sample from one or more individuals within said initial population; [0104] c. detecting in each of said nucleic acid samples the presence of an allele conferring remontancy (“remontancy allele”), wherein the remontancy allele is a heterozygous state at a single nucleotide polymorphism (SNP) locus within SEQ ID NO:11; [0105] d. selecting a strawberry plant from said population of progeny plants based on the presence of the at remontancy allele in the nucleic acid samples; and [0106] e. crossing the selected strawberry plant with a second strawberry plant to produce progeny plants comprising improved agronomic traits.
[0107] Embodiment 23. The method of Embodiment 22, wherein two strawberry plants are selected from said initial population based on the presence of the selected allele in the nucleic acid sample for each of the two selected plants, and wherein the two selected plants are crossed with one another to produce progeny plants comprising improved agronomic traits.
[0108] Embodiment 24. The method of any one of Embodiments 20-23, wherein the detection step further comprises detecting in each of said nucleic acid samples the presence or absence of at least one allele conferring increased berry weight (“berry weight allele”), wherein the at least one berry weight allele is an allele of at least one SNP loci within SEQ ID NOs:12-17.
[0109] Embodiment 25. The method of Embodiment 24, wherein the detection step comprises detecting at least two berry weight alleles of SEQ ID NOs:12-17, optionally at least three berry weight alleles of SEQ ID NOs:12-17, optionally at least four berry weight alleles of SEQ ID NOs:12-17, optionally at least five berry weight alleles of SEQ ID NOs:12-17, or optionally at least six berry weight alleles of SEQ ID NOs:12-17.
[0110] Embodiment 26. The method of any one of Embodiment 24 or Embodiment 25, wherein at least one of the two strawberry plants in the cross is homozygous for the selected berry weight alleles.
[0111] Embodiment 27. The method of any one of Embodiment 24 or Embodiment 25, wherein both of the strawberry plants in the cross are homozygous for the selected berry weight alleles.
EXAMPLES
Background of SNP Analysis and CIPHER™
[0112] By combining genotypic and phenotypic analysis, a SNP marker can be correlated with a particular phenotypic trait, such as a disease resistance trait or agronomic trait. By identifying multiple SNP markers that associate with the same phenotypic trait, it is possible to combine multiple SNP markers into a haplotype that associates even more closely with the desired phenotypic trait.
[0113] CIPHER™ is a technology that identifies a set of SNP markers that can be used, either alone or in combination, to identify, with a high likelihood of success, a particular phenotypic trait among individuals in a population. CIPHER™ uses sequencing of reduced genomes along with measurements of key traits to generate information rich DNA-based profiles across plant populations using machine learning algorithms. The analysis software then rigorously selects a set of key DNA-based predictors and builds a CIPHER™ algorithm that decrypts the predictors into qualitative haplotype (categorical) values and quantitative (numeric) scores for a specific trait. Diagnostic molecular assays using novel DNA extraction with conventional and isothermal polymerase chain reaction (PCR) are designed by the analysis process and the CIPHER™ is physically validated under a blind test in the laboratory setting.
Example 1: Developing and Implementing Fusarium Resistance SNPs and CIPHER™
[0114] SNPs were identified and CIPHERs™ were developed that are capable of identifying, with high accuracy, strawberry plants that possess improved resistance to Fusarium disease, for example disease caused by Fusarium oxysporum f. sp. fragariae, and, conversely, susceptible plants. The CIPHERs™ are based on decryption algorithms which allow qualitative and quantitative scores to be generated from seven loci or predictors for Fusarium (
[0115] The disease CIPHERs™ were developed by carefully selecting a training set of lines. The training set was evaluated for resistance to Fusarium sp., M phaseolina, and C. acutatum under controlled greenhouse conditions over three years (2017, 2018, 2020). The mean disease severity (phenotypes) for each line in the training set were combined with the corresponding cipheralleles (genotypes) and the software developed a preliminary prediction algorithm using its proprietary adaptive learning network. The prediction algorithm was then validated using both cross validation with the appropriate hold-out strategy for the trait type and physical validation. The algorithm was then optimized using a proprietary selection network to identify the smallest subset of predictors or alleles that accurately predict the trait.
[0116] The Fusarium CIPHER™ Algorithm:
where predicted trait or attribute value (
[0117] The sequence information from each locus (
[0118] The imputed trait or attribute values of a test set (N=300 lines) representing five breeding programs that were not screened in the greenhouse experiments were compared to actual disease severity measurements using the Trait CIPHER™ Assays. The comparisons yielded an accuracy of 88% or greater, showing greater than 97% accuracy for Fusarium. When comparing this result to the traditional marker-assisted-selection method currently being deployed, the Fusarium CIPHER™ was on average 40.8% more accurate.
[0119] The Fusarium CIPHER™ was used to cull out Fusarium susceptible lines across the breeding programs (N˜150,000 seedlings) prior to transplanting from the greenhouse to the field. In brief, F.sub.1 seeds were planted in trays and incubated in the greenhouse. Three-millimeter leaf disks were cut from each seedling and placed in a 96-well plate maintaining the line identification using a plate record key. The plates were sent in for Trait CIPHER™ sequencing and the data was uploaded to a database. A workflow utilizing the Fusarium CIPHER™ Algorithm deciphered the data for each line into predicted Fusarium haplotype and severity scores. A culling tool was utilized to set the minimum Fusarium severity score desired and view the overall metrics for percent cull, maximum/minimum severity, and unique severity scores for each cross. Once the desired culling percent was determined via evaluation of the metrices, the wells in each tray containing a line to be culled was identified using a proprietary algorithm embedded in the workflow. In addition, individual tray maps were constructed to guide physically removing the unwanted lines from the trays while consolidating the good lines.
[0120] The overall accuracy of the CIPHER™ algorithm was re-evaluated based on the assumed segregation ratios for each cross and by testing selected lines in the greenhouse under artificial Fusarium disease pressure. Overall, the expected segregation ratios were calculated for the crosses and the selected lines fit the expected disease response greater than 98% of the time.
[0121] A close evaluation of the haplotype representation of all seven allele states that make up the Fusarium CIPHER™ revealed that the optimal allele state:
does not exist in the breeding programs. The theoretical resistance of the optimal haplotype would be 1.5 times greater than currently possible. The program fixes the alleles utilizing the Trait CIPHER™. The Fusarium CIPHER™ can be used to screen a global strawberry population to confirm the uniqueness of this optimal haplotype.
Example 2: Developing and Implementing Macrophomina/Colletotrichum Resistance SNPs and CIPHER™
[0122] SNPs were identified and CIPHERs™ were developed that are capable of identifying, with high accuracy, strawberry plants that possess improved resistance to Macrophomina and/or Colletotrichum disease, for example disease caused by Macrophomina phaseolina or Colletotrichum acutatum, and, conversely, susceptible plants. The CIPHERs™ are based on decryption algorithms which allow qualitative and quantitative scores to be generated from five loci or predictors for Macrophomina and Colletotrichum (
Macrophomina:
[0123]
Colletotrichum:
[0124]
[0125] The sequence information from each locus (
[0126] The imputed trait or attribute values of a test set (N=300 lines) representing five breeding programs that were not screened in the greenhouse experiments were compared to actual disease severity measurements using the Trait CIPHER™ Assays. The optimal allele states were calculated for:
Macrophomina:
[0127]
Colletotrichum:
[0128]
And were not found within the programs.
Example 3: Developing and Implementing Agronomic Trait SNPs and CIPHER™
[0129] SNPs were identified and CIPHERs™ were developed that are capable of identifying, with high accuracy, strawberry plants that express remontancy and increased berry weight, and, conversely, those plants that do not. By including an increasing number of SNPs in the selection criteria, and depending on which combined set of SNPs is selected, it is possible to have a much more selective determination of lines possessing the desired agronomic traits than can be achieved by using only one or a few SNPs. A single locus was discovered where in the heterozygous state conditioned remontancy (
[0130] The Berry weight CIPHER™ included six loci that associate with this phenotypic trait (
where predicted trait or attribute value (
[0131] In addition, the optimal allele state was used which allowed three classes of discrimination including greater than, equal to, or less than 28-gram berries with an accuracy of 85% (
y=28.71+i.sup.1(0*0.80)+i.sup.2(0*−1.11)+i.sup.3(0*−1.11)+i.sup.4(0*−2.70)+i.sup.5(0*−2.04)+i.sup.6(2*1.83)
was not found across the breeding programs.
[0132] It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the present description.
[0133] All documents cited herein are incorporated by reference.