Compositions and methods for enhancing resistance to northern leaf blight in maize

Abstract

The invention relates to methods and compositions for identifying and selecting maize plants with enhanced resistance to northern leaf blight. Maize plants generated by the methods of the invention are also a feature of the invention.

What is claimed: 
     
         1 . A method of selecting a maize plant with enhanced resistance to northern leaf blight, the method comprising:
 a. detecting in the maize plant a first marker allele that is linked to and associated with a haplotype selected from the group consisting of:
 i. the PH26N haplotype at NLB17_A, 
 ii. the PH26N haplotype at NLB17_E, 
 iii. the PH26N haplotype at NLB17 — 3, 
 iv. the PH26N haplotype at NLB18_A, 
 v. the PH26N haplotype at NLB18_E, 
 vi. the PH99N haplotype at NLB18_A, or 
 vii. the PH99N haplotype at NLB18_E; and 
   b. selecting said maize plant that has the first marker allele.   
     
     
         2 . The method of  claim 1 , wherein the first marker allele is linked to the haplotype by 20 cM. 
     
     
         3 . The method of  claim 1 , wherein the first marker allele is linked to the haplotype by 1 cM. 
     
     
         4 . A method of selecting a maize plant with enhanced resistance to northern leaf blight, the method comprising:
 a. detecting in the maize plant a haplotype selected from the group consisting of:
 i. the PH26N haplotype at NLB17_A, 
 ii. the PH26N haplotype at NLB17_E, 
 iii. the PH26N haplotype at NLB17 — 3, 
 iv. the PH26N haplotype at NLB18_A, 
 v. the PH26N haplotype at NLB18_E, 
 vi. the PH99N haplotype at NLB18_A, or 
 vii. the PH99N haplotype at NLB18_E; and 
   b. selecting said maize plant that has said haplotype.   
     
     
         5 . A method of identifying a maize plant that displays enhanced resistance to northern leaf blight, the method comprising detecting in the germplasm of the maize plant an allele of a marker locus wherein:
 a. the marker locus is PHM2798, b0302H1, b0611N13, 2717 — 3, 2717 — 4, 108 f162, 31004, pco642297 — 3, b109.m6, PHM18979, b0507L21, 2 — 2, 156K16, b0318i13, PHM4757, PHM13395-27, PHM4677-11, PHM3418-12, PHM15992-3, NLB5A, NLB3A, PHM4582, 9g13-3, K, 6 — 7, 6 — 8, N, R, S, U, PHM4757, PHM2817-26, PHM7446-6, PHM13395-16, NLB17_A, NLB17_E, NLB17 — 3, NLB18_A, or NLB18_E; and   b. the allele is associated with enhanced resistance to northern leaf blight.   
     
     
         6 . A method of identifying a maize plant that displays enhanced resistance to northern leaf blight, the method comprising detecting in the germplasm of the maize plant a haplotype comprising alleles at one or more marker loci, wherein:
 a. the one or more marker loci are located within a chromosomal interval comprising and flanked by:
 i. markers PHM4582 and R; or 
 ii. 6 — 8 and R; and 
   b. said haplotype is associated with enhanced resistance to northern leaf blight.   
     
     
         7 . The method of  claim 6  wherein the haplotype is: the PH26N haplotype at NLB17_A, the PH26N haplotype at NLB17_E, the PH26N haplotype at NLB17 — 3, the PH26N haplotype at NLB18_A, the PH26N haplotype at NLB18_E, the PH99N haplotype at NLB18_A, or the PH99N haplotype at NLB18_E. 
     
     
         8 . A method of selecting a maize plant that displays enhanced resistance to northern leaf blight, the method comprising:
 a. obtaining a first maize plant that comprises within its genome:
 i. the PH26N haplotype at NLB17_A, 
 ii. the PH26N haplotype at NLB17_E, 
 iii. the PH26N haplotype at NLB17 — 3, 
 iv. the PH26N haplotype at NLB18_A, 
 v. the PH26N haplotype at NLB18_E, 
 vi. the PH99N haplotype at NLB18_A, or 
 vii. the PH99N haplotype at NLB18_E; 
   b. crossing said first maize plant to a second maize plant;   c. evaluating progeny plants for said alleles; and   d. selecting progeny plants that possess said alleles.   
     
     
         9 . A maize plant identified by any of the methods of  claims 5 - 7 . 
     
     
         10 . A maize plant selected by any of the methods of  claims 1 - 4 , and  8 .