Functional & Integrative Genomics

, Volume 9, Issue 3, pp 325–334

A candidate for Lr19, an exotic gene conditioning leaf rust resistance in wheat


  • Andrea Gennaro
    • Department of Agrobiology and AgrochemistryUniversity of Tuscia
  • Robert M. D. Koebner
    • Department of Crop GeneticsJohn Innes Centre
    • Department of Agrobiology and AgrochemistryUniversity of Tuscia
Original Paper

DOI: 10.1007/s10142-009-0115-1

Cite this article as:
Gennaro, A., Koebner, R.M.D. & Ceoloni, C. Funct Integr Genomics (2009) 9: 325. doi:10.1007/s10142-009-0115-1


Lr19, one of the few widely effective genes conferring resistance to leaf rust in wheat, was transferred from the wild relative Thinopyrum ponticum to durum wheat. Since Lr19 confers a hypersensitive response to the pathogen, it was considered likely that the gene would be a member of the major nucleotide-binding site (NBS)-leucine-rich repeat (LRR) plant R gene family. NBS profiling, based on PCR amplification of conserved NBS motifs, was applied to durum wheat–Th. ponticum recombinant lines involving different segments of the alien 7AgL chromosome arm, carrying or lacking Lr19. Differential PCR products were isolated and sequenced. From one such sequence (AG15), tightly linked to Lr19, a 4,121-bp full-length cDNA was obtained. Its deduced 1,258 amino acid sequence has the characteristic NBS-LRR domains of plant R gene products and includes a coiled-coil (CC) region typical of monocots. The genomic DNA sequence showed the presence of two exons and a short intron upstream of the predicted stop codon. Homology searches revealed considerable identity of AG15 with the cloned wheat resistance gene Pm3a and a lower similarity with wheat Lr1, Lr21, and Lr10. Quantitative PCR on leaf-rust-infected and non-infected Lr19 carriers proved AG15 to be constitutively expressed, as is common for R genes.


Triticum durumThinopyrum ponticumNBS-LRR genesRGAsLr19Codominant marker

Supplementary material

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High resolution (EPS 1274 kb)
10142_2009_115_Fig2_ESM.eps (453 kb)
High resolution (EPS 1274 kb)

Copyright information

© Springer-Verlag 2009