Methods and Compositions for Gray Leaf Spot Resistance in Corn

• US 20090064360A1
• Filed: 08/29/2008
• Published: 03/05/2009
• Est. Priority Date: 08/29/2007
• Status: Active Grant

• Current Assignee: Monsanto Technology LLC (Bayer AG)
• Original Assignee: Monsanto Technology LLC (Bayer AG)
• Inventors: Walker, Scott, Pozar, Gilberto, Jia, Hongwu, Kerns, Michael R., Frey, Travis J., Holland, Gregory, Butruille, David, Cook, Kevin
• Granted Patent: US 8,273,944 B2
• Time in Patent Office: Days
• US Class Current: 800/265
• CPC Class Codes: A01H 1/045 using molecular markers
• CPC Class Codes: A01H 5/10 Seeds
• CPC Class Codes: A01H 6/4684 Zea mays [maize]
• CPC Class Codes: C12N 15/8281 for bacterial resistance
• CPC Class Codes: C12N 15/8282 for fungal resistance
• CPC Class Codes: C12Q 1/6895 for plants, fungi or algae
• CPC Class Codes: C12Q 2600/13 Plant traits
• CPC Class Codes: C12Q 2600/156 Polymorphic or mutational markers
• CPC Class Codes: C12Q 2600/172 Haplotypes

Abstract

The present invention relates to the field of plant breeding. More specifically, the present invention includes a method of using haploid plants for genetic mapping of traits of interest such as disease resistance. Further, the invention includes a method for breeding corn plants containing quantitative trait loci (QTL) that are associated with resistance to Gray Leaf Spot, a fungal disease associated with Cercospora spp.

Claims

1. A method of identifying a corn plant comprising at least one allele associated with Gray Leaf Spot (GLS) resistance allele in a corn plant comprising:

a) genotyping at least one corn plant with at least one nucleic acid marker selected from the group consisting of SEQ ID NO;

1-62, 64-70, 72-156, 158-172, 174-187, 189-377, 379, 380, 382-409, 411-459, 461-1233, 1360 and 1361, and

b) selecting at least one corn plant comprising an allele of at least one of said markers associated with Gray Leaf Spot (GLS) resistance.

2. The method according to claim 1, wherein the at least one corn plant genotyped in step (a) and/or the at least one corn plant selected in step (b) is a corn plant from a population generated by a cross.

3. The method of claim 2, wherein said cross is effected by mechanical emasculation, chemical sterilization, or genetic sterilization of a pollen acceptor.

4. The method of claim 1, wherein genotyping is effected in step (a) by determining the allelic state of at least one of said corn genomic DNA markers.

5. The method according to claim 1, wherein the selected one or more corn plants exhibit at least partial resistance to a GLS-inducing fungus or at least substantial resistance to a GLS-inducing fungus.

6. The method of claim 2, wherein said population is generated by a cross of at least one Gray Leaf Spot (GLS) resistant corn plant with at least one Gray Leaf Spot (GLS) sensitive corn plant.

7. The method of claim 2, wherein said population is a segregating population.

8. The method of claim 2, wherein said cross is a back cross of at least one Gray Leaf Spot (GLS) resistant corn plant with at least one Gray Leaf Spot (GLS) sensitive corn plant to introgress GLS resistance into a corn germplasm.

9. The method of claim 2, wherein said population is a haploid breeding population.

18. A corn plant obtained by the method of claim 1, wherein said corn plant comprises at least one allele of a nucleic acid marker selected from the group consisting of SEQ ID NO:

1-62, 64-70, 72-156, 158-172, 174-187, 189-377, 379, 380, 382-409, 411-459, 461-1233, 1360 and 1361, wherein said allele is associated with Gray Leaf Spot (GLS) resistance.

19. The corn plant of claim 18, wherein the corn plant exhibits at least partial resistance to a GLS-inducing fungus or at least substantial resistance to a GLS-inducing fungus.

20. The corn plant of claim 19, wherein said corn plant is a haploid corn plant.

10. A method of introgressing a Gray Leaf Spot (GLS) resistance QTL allele into a corn plant comprising:

a) screening a population with at least one nucleic acid marker to determine if one or more corn plants from the population comprise(s) an allele of said marker associated with a Gray Leaf Spot (GLS) resistance QTL selected from the group consisting of QTL numbers 1-9, 14-33, 35, 38-42, 44-52, 54-61, 63-71, 73-79, 81-92, 95-96, 99-106, 108-117, and 119-178 as provided in FIG. 1; and

b) selecting from said population at least one corn plant comprising an allele of said marker associated with a Gray Leaf Spot (GLS) resistance.

11. The method according to claim 10, wherein at least one of the markers is located within 5 cM of at least one of said Gray Leaf Spot (GLS) resistance QTL.

12. The method according to claim 11, wherein at least one of the markers is located within 2 cM of at least one of said Gray Leaf Spot (GLS) resistance QTL.

13. The method according to claim 12, wherein at least one of the markers is located within 1 cM of at least one of said Gray Leaf Spot (GLS) resistance QTL.

14. The method according to claim 10, wherein at least one of the markers exhibits a LOD score of greater than 4.0 with at least one of said Gray Leaf Spot (GLS) resistance QTL.

15. The method according to claim 10, wherein said population is generated by a cross of at least one Gray Leaf Spot (GLS) resistant corn plant with at least one Gray Leaf Spot (GLS) sensitive corn plant.

16. The method of claim 10, wherein said population is a haploid breeding population.

17. The method of claim 10, wherein said nucleic acid marker is selected from the group consisting of SEQ ID NOs:

858, 860, 862, 866, 875, 877, 881, 882, 883, and 1360.

21. A corn plant obtained by the method of claim 10, wherein said corn plant comprises a Gray Leaf Spot (GLS) resistance QTL selected from the group consisting of QTL numbers 1-9, 14-33, 35, 38-42, 44-52, 54-61, 63-71, 73-79, 81-92, 95-96, 99-106, 108-117, and 119-178 as provided in FIG. 1.

22. An isolated nucleic acid molecule for detecting a molecular marker representing a polymorphism in corn DNA, wherein said nucleic acid molecule comprises at least 15 nucleotides that include or are immediately adjacent to said polymorphism, wherein said nucleic acid molecule is at least 90 percent identical to a sequence of the same number of consecutive nucleotides in either strand of DNA that include or are immediately adjacent to said polymorphism, and wherein said molecular marker is selected from the group consisting of SEQ ID NOs:

1-26, 28-62, 64-70, 72-120, 122-140, 142-156, 158-172, 174, 176, 178-187, 189-219, 221-223, 225-233, 235-247, 249-251, 253-377, 379, 380, 382-409, 411-439, 441-459, 461-478, 481-532, 534-581, 583-584, 586-638, 640-720, 722-726, 728-732, 734-745, 747-767, 769-772, 774-939, 941-1052, 1055-1121, 1123-1185, 1187-1233, 1304 through SEQ ID NO;

1331, 1360, and 1361.

23. The isolated nucleic acid molecule of claim 22, wherein said molecular marker is selected from the group consisting of SEQ ID NOs:

858, 860, 862, 866, 875, 877, 881, 882, 883, and 1360.