Soybean Seed And Oil Compositions And Methods of Making Same

Abstract

Methods for obtaining soybean plants that produce seed with low linolenic acid levels and moderately increased oleic levels are disclosed. Also disclosed are methods for producing seed with low linolenic acid levels, moderately increased oleic levels and low saturated fatty acid levels. These methods entail the combination of transgenes that provide moderate oleic acid levels with soybean germplasm that contains mutations in soybean genes that confer low linolenic acid phenotypes. These methods also entail the combination of transgenes that provide both moderate oleic acid levels and low saturated fat levels with soybean germplasm that contains mutations in soybean genes that confer low linolenic acid phenotypes. Soybean plants and seeds produced by these methods are also disclosed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and together with the description, serve to explain the principles of the invention. In the drawings:

FIG. 1 illustrates pCGN5469, a plant vector for decreasing expression of the soybean FAD2-1 gene;

FIG. 2 illustrates pCGN5471, a plant vector for decreasing expression of the soybean FAD2-1 gene;

FIG. 3 illustrates pCGN5485, a plant vector for decreasing expression of the soybean FAD2-1 gene; and

FIG. 4 illustrates exemplary plant vector configurations for decreasing expression of one or more genes by using the DNA sequence elements from the soybean genes listed in Table 1.

FIG. 5 illustrates exemplary plant vector configurations for decreasing expression of one or more genes by using the DNA sequence elements from the soybean FAD2-1 and/or soybean FATB genes listed in Table 2.

FIG. 6 illustrates exemplary plant vectors for decreasing expression of both the endogenous soybean FAD2-1 and FATB genes.

Claims

1. A method of producing a soybean plant comprising a linolenic acid content of less than about 6% of total seed fatty acids by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight, comprising the steps of: a) making one or more soybean plants that comprise a transgene that decreases the expression of an endogenous soybean FAD2-1 gene and at least one loss-of-function mutation in an endogenous soybean FAD3 gene;b) obtaining at least one seed from said soybean plant obtained in step (a);c) determining a percentage of the total seed fatty acid content by weight of linolenic acid and oleic acid for said seed of step (b); and,d) identifying a soybean plant that yields seed having a seed fatty acid composition comprising a linolenic acid content of less than about 6% of total seed fatty acids by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

2. The method of claim 1, wherein said soybean plants that are made in step (a) comprise at least two loss of function mutations in at least two endogenous soybean FAD3 genes.

3. The method of claim 2, wherein said endogenous soybean FAD3 genes are FAD3-1B and FAD3-1C.

4. The method of claim 2, wherein said soybean plant identified in step 3 comprises a linolenic acid content of less than about 3% of total seed fatty acids by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

5. The method of claim 1, wherein said soybean plant is made in step (a) by: i) crossing a first soybean parent line comprising said transgene with a second soybean parent line comprising at least one loss-of-function mutation in an endogenous soybean FAD3 gene to obtain an F1 soybean plant that is heterozygous for said transgene and heterozygous for at least one loss of function mutation in a FAD3 gene; andii) selfing F1 progeny plants from (i) to obtain an F2 soybean plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene, thereby obtaining a soybean plant comprising both a transgene that decreases the expression of an endogenous soybean FAD2-1 gene and at least one loss-of-function mutation in an endogenous soybean FAD3 gene.

6. The method of claim 5, wherein said second soybean parent line comprises at least two loss of function mutations in at least two endogenous soybean FAD3 genes.

7. The method of claim 6, wherein said endogenous soybean FAD3 genes are FAD3-1B and FAD3-1C.

8. The method of claim 5, wherein said F1 soybean plant that is heterozygous for said transgene and for at least one loss of function mutation in a FAD3 gene is obtained in step (i) by subjecting a plurality of F1 plants to at least one DNA analysis technique permitting identification of an F1 plant that is heterozygous for said transgene and for at least one loss of function mutation in a FAD3 gene.

9. The method of claim 5, wherein said F2 soybean plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene is obtained in step (ii) by subjecting a plurality of F2 plants to at least one DNA analysis technique permitting identification of an F2 plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene.

10. The method of claim 8, wherein said DNA analysis technique comprises one or more techniques selected from the group consisting of PCR analysis, quantitative PCR analysis, SNP analysis, AFLP analysis, RFLP analysis and RAPD analysis.

11. The method of claim 9, wherein said DNA analysis technique comprises one or more techniques selected from the group consisting of PCR analysis, quantitative PCR analysis, SNP analysis, AFLP analysis, RFLP analysis and RAPD analysis.

12. The method of claim 8, wherein said DNA analysis technique comprises detection of at least one single nucleotide polymorphism at a position in the FAD3-1C gene sequence corresponding to nucleotide 687, 1129, 1203, 2316, 3292, 3360 or 3743 of SEQ ID NO:62, detection of a deletion in the FAD3-1C gene of SEQ ID NO:62, or detection of at least one single nucleotide polymorphism in a soybean FAD3-1C promoter sequence corresponding to a guanine at nucleotide 334, a cytosine at nucleotide 364, a thymine at nucleotide 385, an adenine at nucleotide 387, a cytosine at nucleotide 393, a guanine at nucleotide 729 and a cytosine at nucleotide 747 of SEQ ID NO:63.

13. The method of claim 9, wherein said DNA analysis technique comprises detection of at least one single nucleotide polymorphism at a position in the FAD3-1C gene sequence corresponding to nucleotide 687, 1129, 1203, 2316, 3292, 3360 or 3743 of SEQ ID NO:62, detection of a deletion in the FAD3-1C gene of SEQ ID NO:62, or detection of at least one single nucleotide polymorphism in a soybean FAD3-1C promoter sequence corresponding to a guanine at nucleotide 334, a cytosine at nucleotide 364, a thymine at nucleotide 385, an adenine at nucleotide 387, a cytosine at nucleotide 393, a guanine at nucleotide 729 and a cytosine at nucleotide 747 of SEQ ID NO:63.

14. The method of claim 8, wherein said DNA analysis technique comprises detection of a single nucleotide polymorphism in said soybean FAD3-1B gene comprising a substitution of a thymine residue for a cytosine residue at a position in the FAD3-1B gene sequence corresponding to nucleotide 2021 of SEQ ID NO:61.

15. The method of claim 9, wherein said DNA analysis technique comprises detection of mutation in said soybean FAD3-1B gene comprising a substitution of a thymine residue for a cytosine residue at a position in the FAD3-1B gene sequence corresponding to nucleotide 2021 of SEQ ID NO:61.

16. The method of claim 1, wherein said transgene further comprises a transgene that confers herbicide tolerance.

17. The method of claim 5, wherein said transgene further comprises a transgene that confers herbicide tolerance and wherein said F1 soybean plant that is heterozygous for said transgene is obtained in step (i) by subjecting a plurality of F1 plants to herbicide selection for said transgene.

18. The method of claim 5, wherein said transgene further comprises a transgene that confers herbicide tolerance and wherein a plurality of F2 plants enriched for F2 soybean plants that are homozygous for said transgene are obtained in step (ii) by subjecting said plurality of F2 plants to herbicide selection for said transgene.

19. The method of claim 16, wherein said herbicide is glyphosate.

20. The method of claim 16, wherein said transgene comprises sequences located between the T-DNA border sequences of pMON68504, pCGN5469, pCGN5471, or pCGN5485 that are integrated into a chromosome of said plant.

21. The method of claim 1, said soybean plant is made in step (a) by: a) transforming a soybean plant or soybean plant cell comprising at least one loss-of-function mutation in an endogenous soybean FAD3 gene with a transgene that decreases the expression of endogenous soybean FAD2-1 gene to obtain an R0 soybean plant with least one loss of function mutation in a FAD3 gene that is heterozygous for said transgene;b) selfing said R0 progeny plant from (i) to obtain an R1 soybean plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene, thereby obtaining a soybean plant comprising a transgene that decreases the expression of an endogenous soybean FAD2-1 gene and at least one loss-of-function mutation in an endogenous soybean FAD3 gene.

22. The method of claim 21, wherein said transgene further comprises sequences that confer a herbicide tolerance trait.

23. The method of claim 22, wherein said herbicide is glyphosate.

24. The method of claim 5, further comprising the step iii) selfing said F2 progeny plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene from (ii) to obtain an F3 soybean plant.

25. The method of claim 1, wherein said percentage of the total seed fatty acid content by weight of linolenic acid and oleic acid is determined in step (c) by a lipid analysis technique.

26. The method of claim 25, wherein said lipid analysis technique comprises one or more techniques selected from the group consisting of gas chromatography/flame ionization detection, gas chromatography/mass spectroscopy, thin layer chromatography/flame ionization detection, liquid chromatography/mass spectrometry, liquid chromatography/electrospray ionization-mass spectrometry and liquid chromatography/electrospray ionization-tandem mass spectroscopy.

27. A soybean plant produced by the method of claim 1.

28. A plant part of the soybean plant of claim 27.

29. The plant part of claim 28, wherein said plant part is pollen, an ovule, a meristem, a leaf, a stem, a root, or a cell.

30. A progeny soybean plant from the soybean plant of claim 27.

31. A seed of the soybean plant produced by the method of claim 1, said seed having a fatty acid composition comprising a linolenic acid content of less than about 6% of total seed fatty acids by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

32. A seed of the soybean plant produced by the method of claim 4, said seed having a fatty acid composition comprising a linolenic acid content of less than about 3% of total seed fatty acids by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

33. A method of obtaining a soybean plant with an altered seed oil fatty acid composition comprising the steps of: a) crossing a first soybean parent line having a seed oil fatty acid composition comprising a linolenic acid content of less than about 3% of total fatty acids by weight with a second soybean parent line having a seed oil fatty acid composition wherein the content of at least one fatty acid other than linoleic acid is altered by at least 50% when compared to the corresponding fatty acid content of a commodity soybean oil, said second soybean parent line comprising a transgene that alters the content of at least one fatty acid other than linoleic acid; andb) obtaining a progeny plant exhibiting a seed oil fatty acid composition comprising a linolenic acid content of less than 3% of total fatty acids by weight and a content of at least one fatty acid other than linoleic acid that is altered by at least 50% when compared to the corresponding fatty acid content of a commodity soybean oil, thereby obtaining a soybean plant with an altered seed oil fatty acid composition.

34. The method of claim 33, wherein said fatty acid other than linolenic acid is selected from the group consisting of lauric acid, myristic acid, palmitic acid, stearic acid, stearidonic acid, oleic acid, linoleic acid, γ-linoleic acid, eicosapentaenoic acid and docosahexaenoic acid.

35. The method of claim 24, wherein said fatty acid other than linolenic acid is selected from the group consisting of lauric acid, myristic acid, palmitic acid, stearic acid, stearidonic acid, oleic acid, linoleic acid, γ-linoleic acid, eicosapentaenoic acid and docosahexaenoic acid.

36. A method of producing a soybean plant comprising a linolenic acid content of less than about 6% of total seed fatty acids by weight, a saturated fatty acid content of less than about 8% by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight, comprising the steps of: a) making one or more soybean plants that comprise at least one transgene that decreases the expression of both an endogenous soybean FAD2-1 and an endogenous FATB gene, and at least one loss-of-function mutation in an endogenous soybean FAD3 gene;b) obtaining at least one seed from said soybean plant obtained in step (a);c) determining a percentage of the total seed fatty acid content by weight of linolenic acid, saturated fatty acids and oleic acid for said seed of step (b); and,d) identifying a soybean plant that yields seed having a seed fatty acid composition comprising a linolenic acid content of less than about 6% of total seed fatty acids by weight, a saturated fatty acid content of less than about 8% by weight, and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

37. The method of claim 36, wherein said soybean plants that are made in step (a) comprise at least two loss of function mutations in at least two endogenous soybean FAD3 genes.

38. The method of claim 37, wherein said endogenous soybean FAD3 genes are FAD3-1B and FAD3-1C.

39. The method of claim 38, wherein said soybean plant identified in step 3 comprises a linolenic acid content of less than about 3% of total seed fatty acids by weight, a saturated fatty acid content of less than about 8% by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

40. The method of claim 36, wherein said soybean plant is made in step (a) by: i) crossing a first soybean parent line comprising said transgene with a second soybean parent line comprising at least one loss-of-function mutation in an endogenous soybean FAD3 gene to obtain an F1 soybean plant that is heterozygous for said transgene and heterozygous for at least one loss of function mutation in a FAD3 gene; andii) selfing F1 progeny plants from (i) to obtain an F2 soybean plant that is homozygous for said transgenes and homozygous for at least one loss of function mutation in a FAD3 gene, thereby obtaining a soybean plant comprising at least one transgene that decreases the expression of both an endogenous soybean FAD2-1 and an endogenous FATB gene and at least one loss-of-function mutation in an endogenous soybean FAD3 gene.

41. The method of claim 40, wherein said F1 soybean plant that is heterozygous for said transgene and for at least one loss of function mutation in a FAD3 gene is obtained in step (i) by subjecting a plurality of F1 plants to at least one DNA analysis technique permitting identification of an F1 plant that is heterozygous for said transgene and for at least one loss of function mutation in a FAD3 gene.

42. The method of claim 40, wherein said F2 soybean plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene is obtained in step (ii) by subjecting a plurality of F2 plants to at least one DNA analysis technique permitting identification of an F2 plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene.

43. The method of claim 41, wherein said DNA analysis technique comprises detection of at least one single nucleotide polymorphism at a position in the FAD3-1C gene sequence corresponding to nucleotide 687, 1129, 1203, 2316, 3292, 3360 or 3743 of SEQ ID NO:62, detection of a deletion in the FAD3-1C gene of SEQ ID NO:62, or detection of at least one single nucleotide polymorphism in a soybean FAD3-1C promoter sequence corresponding to a guanine at nucleotide 334, a cytosine at nucleotide 364, a thymine at nucleotide 385, an adenine at nucleotide 387, a cytosine at nucleotide 393, a guanine at nucleotide 729 and a cytosine at nucleotide 747 of SEQ ID NO:63.

44. The method of claim 42, wherein said DNA analysis technique comprises detection of at least one single nucleotide polymorphism at a position in the FAD3-1C gene sequence corresponding to nucleotide 687, 1129, 1203, 2316, 3292, 3360 or 3743 of SEQ ID NO:62, detection of a deletion in the FAD3-1C gene of SEQ ID NO:62, or detection of at least one single nucleotide polymorphism in a soybean FAD3-1C promoter sequence corresponding to a guanine at nucleotide 334, a cytosine at nucleotide 364, a thymine at nucleotide 385, an adenine at nucleotide 387, a cytosine at nucleotide 393, a guanine at nucleotide 729 and a cytosine at nucleotide 747 of SEQ ID NO:63.

45. The method of claim 41, wherein said DNA analysis technique comprises detection of a single nucleotide polymorphism in said soybean FAD3-1B gene comprising a substitution of a thymine residue for a cytosine residue at a position in the FAD3-1B gene sequence corresponding to nucleotide 2021 of SEQ ID NO:61.

46. The method of claim 42, wherein said DNA analysis technique comprises detection of a single nucleotide polymorphism in said soybean FAD3-1B gene comprising a substitution of a thymine residue for a cytosine residue at a position in the FAD3-1B gene sequence corresponding to nucleotide 2021 of SEQ ID NO:61.

47. The method of claim 36, wherein said transgene further comprises a transgene that confers herbicide tolerance.

48. The method of claim 40, wherein said transgene further comprises a transgene that confers herbicide tolerance and wherein said F1 soybean plant that is heterozygous for said transgene is obtained in step (i) by subjecting a plurality of F1 plants to herbicide selection for said transgene.

49. The method of claim 40, wherein said transgene further comprises a transgene that confers herbicide tolerance and wherein a plurality of F2 plants enriched for F2 soybean plants that are homozygous for said transgene are obtained in step (ii) by subjecting said plurality of F2 plants to herbicide selection for said transgene.

50. The method of claim 47, wherein said herbicide is glyphosate.

51. The method of claim 47, wherein said transgene comprises a CP4 EPSPS gene.

52. The method of claim 36, said soybean plant is made in step (a) by: a) transforming a soybean plant or soybean plant cell comprising at least one loss-of-function mutation in an endogenous soybean FAD3 gene with at least one transgene that decreases the expression of both an endogenous soybean FAD2-1 and an endogenous soybean FATB gene to obtain an R0 soybean plant with least one loss of function mutation in a FAD3 gene that is heterozygous for said transgene;b) selfing said R0 progeny plant from (i) to obtain an R1 soybean plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene, thereby obtaining a soybean plant comprising said transgene and at least one loss-of-function mutation in an endogenous soybean FAD3 gene.

53. The method of claim 52, wherein said transgene further comprises sequences that confer a herbicide tolerance trait.

54. The method of claim 53, wherein said herbicide is glyphosate.

55. The method of claim 40, further comprising the step iii) selfing said F2 progeny plant that is homozygous for said transgene and homozygous for at least one loss of function mutation in a FAD3 gene from (ii) to obtain an F3 soybean plant.

56. The method of claim 36, wherein said percentage of the total seed fatty acid content by weight of linolenic acid, saturated fatty acids and oleic acid is determined in step (c) by a lipid analysis technique.

57. The method of claim 56, wherein said lipid analysis technique comprises one or more techniques selected from the group consisting of gas chromatography/flame ionization detection, gas chromatography/mass spectroscopy, thin layer chromatography/flame ionization detection, liquid chromatography/mass spectrometry, liquid chromatography/electrospray ionization-mass spectrometry and liquid chromatography/electrospray ionization-tandem mass spectroscopy.

58. A soybean plant produced by the method of claim 36.

59. A plant part of the soybean plant of any one of claim 58.

60. The plant part of claim 59, wherein said plant part is pollen, an ovule, a meristem, a leaf, a stem, a root, or a cell.

61. A progeny soybean plant from the soybean plant of claim 58.

62. A seed of the soybean plant produced by the method of claim 36, said seed having a fatty acid composition comprising a linolenic acid content of less than about 6% of total seed fatty acids by weight, a saturated fatty acid content of less than about 8% by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.

63. A seed of the soybean plant produced by the method of claim 39, said seed having a fatty acid composition comprising a linolenic acid content of less than about 3% of total seed fatty acids by weight, a saturated fatty acid content of less than about 8% by weight and an oleic acid content of about 55% to about 80% of total seed fatty acids by weight.