Combination of all-stage and high-temperature adult-plant resistance QTL confers high-level, durable resistance to stripe rust in winter wheat cultivar Madsen

Abstract

Wheat cultivar Madsen has a new gene on the short arm of chromosome 1A and two QTL for all-stage resistance and three QTL for high-temperature adult-plant resistance that in combination confer high-level, durable resistance to stripe rust. Wheat cultivar Madsen has maintained a high-level resistance to stripe rust over 30 years. To map quantitative trait loci (QTL) underlying the high-level, durable resistance, 156 recombinant inbred lines (RILs) developed from cross Avocet S × Madsen were phenotyped with selected races of Puccinia striiformis f. sp. tritici in the greenhouse seedling tests, and in naturally infected fields during 2015-2017. The RILs were genotyped by SSR and SNP markers from genotyping by sequencing and the 90 K wheat SNP chip. Three QTL for all-stage resistance were mapped on chromosomes 1AS, 1BS and 2AS, and two QTL for high-temperature adult-plant (HTAP) resistance were mapped on 3BS and 6BS. The most effective QTL on 2AS, explaining 8.97-23.10% of the phenotypic variation in seedling tests and 8.60-71.23% in field tests, contained Yr17 for all-stage resistance and an additional gene for HTAP resistance. The 6BS QTL, detected in all field tests, was identified as Yr78. The 1AS QTL, conferring all-stage resistance, was identified as a new gene, which explained 20.45 and 30.23% of variation in resistance to races PSTv-37 and PSTv-40, respectively, and contributed significantly to field resistance at Pullman in 2015-2017, but was not detected at Mount Vernon. The interactions among QTL were mostly additive, and RILs with all five QTL had the highest level of resistance in the field, similar to Madsen. Genotyping 148 US Pacific Northwest wheat cultivars with markers for the 1AS, 2AS and 6BS QTL validated the genes and markers, and indicated their usefulness for marker-assisted selection.

Mapping Quantitative Trait Loci for High-Temperature Adult-Plant Resistance to Stripe Rust in Spring Wheat PI 197734 Using a Doubled Haploid Population and Genotyping by Multiplexed Sequencing

“…DH lines with more QTL showed higher resistance, demonstrating that pyramiding multiple HTAP QTL each with partial resistance can improve the level of resistance, even to the high level in PI 197734, without producing any uredinia. The results agree with previous studies that combining different genes for HTAP resistance can achieve high level, durable resistance to stripe rust (Liu et al, 2018(Liu et al, , 2019bLiu L. et al, 2020;Mu et al, 2020).…”

“…Thus, the QTL relationship of QYr197734.wgp-3B and QYr.cim-3B could not be established in the present study using haplotypes of multiple SNPs. QYrPI197734.wgp-3B are closely linked with QYrMa.wgp-3BS (Liu et al, 2018), QYrco.wpg-3BS.2 (Case et al, 2014). As both QYrMa.wgp-3BS and QYrco.wpg-3BS.2 were identified, respectively, in winter wheat cultivars Madsen and Coda developed in the US Pacific Northwest and likely to be the same QTL (Liu et al, 2018), QYrPI197734.wgp-3B may be different, but a further study is needed to clearly determine their relationship.…”

“…QYrPI197734.wgp-3B are closely linked with QYrMa.wgp-3BS (Liu et al, 2018), QYrco.wpg-3BS.2 (Case et al, 2014). As both QYrMa.wgp-3BS and QYrco.wpg-3BS.2 were identified, respectively, in winter wheat cultivars Madsen and Coda developed in the US Pacific Northwest and likely to be the same QTL (Liu et al, 2018), QYrPI197734.wgp-3B may be different, but a further study is needed to clearly determine their relationship. Yr80 for adult plant resistance was mapped in wheat landrace Aus27284 (Nsabiyera et al, 2018).…”

“…Haplotypes of two or more markers can greatly improve the accuracy for MAS. The haplotype approach has been used in previous studies to indicate the presence and absence of resistance genes or QTL (Feng et al, 2015(Feng et al, , 2018Xiang et al, 2016;Liu et al, 2018Liu et al, , 2019bLiu Y. et al, 2020). In the present study, we genotyped 95 spring wheat cultivars and breeding lines developed and grown in the U.S. Pacific Northwest with three KASP markers for YrQPI197734-1A and four KASP markers for YrQPI197734-3B converted from the GMS-SNP markers within the QTL regions (Supplementary Table S3).…”

Revealing Differentially Expressed Genes and Identifying Effector Proteins of Puccinia striiformis f. sp. tritici in Response to High-Temperature Seedling Plant Resistance of Wheat Based on Transcriptome Sequencing

“…HTAP resistance to Pst in wheat has been successfully used in the United States for many years (7). Several Yr genes have been characterized as conferring HTAP resistance, such as Yr18, Yr29, Yr36, Yr39, Yr48, Yr52, Yr59, Yr62, Yr78, and Yr79 and several quantitative trait loci (QTL) (56)(57)(58)(59)(60)(61)(62)(63)(64)(65)(66)(67). However, most of these resistance genes have not been verified as effective or widely used in breeding in China.…”