Molecular analyses in wheat and <i>Aegilops tauschii</i> reveal a new orthologue of the leaf rust resistance gene <i>Lr19</i> on chromosome 7DL of <i>Ae. tauschii</i>

Leaf rust is one of the most devastating wheat diseases worldwide, to which many resistance genes have been successfully introgressed from wild relatives. Though Thinopyrum ponticum-derived leaf gene Lr19 widely effective, and previous studies shown its likely presence in Aegilops tauschii, no thorough investigation has conducted confirm this. The current study examined Ae. tauschii using molecular bioinformatic analyses. Accordingly, cultivar Thatcher was used as a susceptible control, Lr19-carrying genotypes; + (TcLr19) Agatha were resistant controls. Phenotyping pathotype CDHLQ accompanied with genotyping two DNA markers verified results an orthologue for on chromosome 7DL (AtLr19). Sequencing STS GB marker products TcLr19 showed 99% homology between corresponding fragments, confirming phenotyping results. Both sequenced fragments matched melatonin biosynthesis gene, O-methyltransferase-2 (OMT2). A hierarchical network reconstructed all identified putative within genomic region containing 2.5 cM upstream downstream OMT2. Results indicated that numerous important biotic stress-responsive such RPM1, RGA2, TRIUR3, BURP12 myosin-11, located master regulator molecule through OMT2 node. To our knowledge, this first report identification provides insights into possible regulatory route gene.