Summary: | Stripe rust, caused by <i>Puccinia striiformis</i> f. sp. <i>tritici</i> (<i>Pst</i>), is one of the most destructive diseases of wheat in the world. Genetic resistance is the best strategy for control of the disease. Spring wheat landrace PI 181410 has shown high level resistance to stripe rust. The present study characterized the landrace to have both race-specific all-stage resistance and nonrace-specific high-temperature adult-plant (HTAP) resistance. To map quantitative trait loci (QTL) for the resistance in PI 181410, it was crossed with Avocet S (AvS), from which a recombinant inbred line population was developed. The F<sub>5</sub>−F<sub>8</sub> populations were consecutively phenotyped for stripe rust response in multiple field environments under natural <i>Pst</i> infection, and the F<sub>7</sub> population was phenotyped in seedlings at low temperature and in adult-plant stage with selected <i>Pst</i> races in the greenhouse. The F<sub>7</sub> population was genotyped using the 90K wheat SNP chip. Three QTL, <i>QYrPI181410.wgp-4AS</i>, <i>QYrPI181410.wgp-4BL</i>, and <i>QYrPI181410.wgp-5BL</i>.1, from PI 181410 for all-stage resistance, were mapped on chromosome arms 4AS, 4BL, and 5BL, respectively. Four QTL, <i>QYrPI181410.wgp-1BL</i>, <i>QYrPI181410.wgp-4BL</i>, <i>QYrPI181410.wgp-5AS</i>, and <i>QYrPI181410.wgp-5BL.2</i>, were identified from PI 181410 for HTAP resistance and mapped to 1BL, 4BL, 5AS, and 5BL, respectively. Two QTL with minor effects on stripe rust response were identified from AvS and mapped to 2BS and 2BL. Four of the QTL from PI 181410 and one from AvS were potentially new. As the 4BL QTL was most effective and likely a new gene for stripe rust resistance, three kompetitive allele specific PCR (KASP) markers were developed for incorporating this gene into new wheat cultivars.
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