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ARS Home » Plains Area » Manhattan, Kansas » Center for Grain and Animal Health Research » Hard Winter Wheat Genetics Research » Research » Publications at this Location » Publication #364788
Research Project: Genetic Improvement of Biotic and Abiotic Stress Tolerance and Nutritional Quality in Hard Winter Wheat

Location: Hard Winter Wheat Genetics Research

Title: Fine mapping of wheat leaf rust resistance gene Lr42

Author
item GILL, HARSIMARDEEP S - South Dakota State University
item CHUNXIAN, LI - Kansas State University
item JAGDEEP, SIDHU - South Dakota State University
item WENXUAN, LIU - Kansas State University
item WILSON, DUANE - Kansas State University
item Bai, Guihua
item GILL, BIKRAM - Kansas State University
item SEHGAL, SUNISH - South Dakota State University

Submitted to: International Journal of Molecular Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/14/2019
Publication Date: 5/17/2019
Citation: Gill, H., Chunxian, L., Jagdeep, S.S., Wenxuan, L., Wilson, D., Bai, G., Gill, B.S., Sehgal, S.K. 2019. Fine mapping of wheat leaf rust resistance gene Lr42. International Journal of Molecular Sciences. 20:2445. https://doi.org/10.3390/ijms20102445.
DOI: https://doi.org/10.3390/ijms20102445

Interpretive Summary: Leaf rust is one of the most important diseases of wheat worldwide. The gene Lr42 provides moderate resistance to leaf rust at all plant stages. We mapped Lr42 to a small interval on wheat chromosome 1DS. This interval includes seven to nine candidate resistance genes for Lr42. This information may lead to cloing of Lr42. Two DNA markers (SNP113325 and TC387992) flanking Lr42 developed in this study can be used for marker-assisted selection for Lr42 in wheat breeding programs.

Technical Abstract: Leaf rust caused by Puccinia triticina Eriks is one of the most problematic diseases of wheat throughout the world. The gene Lr42 confers effective resistance against leaf rust at both seedling and adult plant stages. Previous studies had reported Lr42 to be both recessive and dominant in hexaploid wheat; however, in diploid Aegilops tauschii (TA2450), we found Lr42 to be dominant by studying segregation in two independent F2 and their F2:3 populations. We further fine-mapped Lr42 in hexaploid wheat using a KS93U50/ Morocco F5 recombinant inbred line (RIL) population to a 3.7 cM genetic interval flanked by markers TC387992 and WMC432. The 3.7 cM Lr42 region physically corresponds to a 3.16 Mb genomic region on chromosome 1DS based on the Chinese Spring reference genome (RefSeq v.1.1) and a 3.5 Mb genomic interval on chromosome 1 in the Ae. tauschii reference genome. This region includes nine nucleotide-binding domain leucine-rich repeat (NLR) genes in wheat and seven in Ae. tauschii, respectively, and these are the likely candidates for Lr42. Furthermore, we developed two kompetitive allele-specific polymorphism (KASP) markers (SNP113325 and TC387992) flanking Lr42 to facilitate marker-assisted selection for rust resistance in wheat breeding programs