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Genome-wide identification of QTL conferring high-temperature adult-plant (HTAP) resistance to stripe rust (Puccinia striiformis f. sp. tritici) in wheat

Author:
Chen, Jianli, Chu, Chenggen, Souza, Edward J., Guttieri, Mary J., Chen, Xianming, Xu, Steven, Hole, David, Zemetra, Robert
Source:
Molecular breeding 2012 v.29 no.3 pp. 791
ISSN:
1380-3743
Subject:
Puccinia striiformis, alleles, chromosome mapping, cultivars, disease resistance, disease severity, genetic markers, germplasm, inbred lines, loci, microsatellite repeats, phenotypic variation, quantitative trait loci, rust diseases, seed storage proteins, wheat
Abstract:
High-temperature adult-plant (HTAP) resistance to stripe rust (caused by Puccinia striiformis f. sp. tritici) is a durable type of resistance in wheat. The objective of this study was to identify quantitative trait loci (QTL) conferring HTAP resistance to stripe rust in a population consisting of 169 F8:10 recombinant inbred lines (RILs) derived from a cross between a susceptible cultivar ‘Rio Blanco’ and a resistant germplasm IDO444. HTAP resistance was evaluated for both disease severity and infection type under natural infection over two years at two locations. The genetic linkage maps covering almost the whole genome with an average density of 6.7 cM per marker were constructed using 484 markers including 96 SSRs, 384 DArTs, two STSs from semidwarf genes Rht1 and Rht2 and another two markers for low-molecular-weight glutenin subunits of seed storage protein. QTL analysis detected a total of eight QTLs significantly associated with HTAP resistance to stripe rust with two on chromosome 2B, two on 3B and one on each of 1A, 4A, 4B and 5B. QTLs on chromosomes 2B and 4A were the major loci derived from IDO444 and explained up to 47% and 42% of the phenotypic variation, respectively. The remaining five QTLs had relatively smaller effects with each accounting for 7 to 10% of the trait variation and were detected in part of the data sets. Of these minor QTLs, the resistant alleles at both QYrrb.ui-3B.1 and QYrrb.ui-4B derived from Rio Blanco and reduced infection type only. The resistant alleles at the remaining three QTLs, QYrid.ui-1A, QYrid.ui-3B.2 and QYrid.ui-5B, were all derived from IDO444 and reduced either infection type or disease severity. Markers linked to 2B and 4A QTLs should be useful for selection of HTAP resistance to stripe rust. High-temperature adult-plant (HTAP) resistance to stripe rust (caused by Puccinia striiformis f. sp. tritici) is a durable type of resistance in wheat. The objective of this study was to identify quantitative trait loci (QTL) conferring HTAP resistance to stripe rust in a population consisting of 169 F8:10 recombinant inbred lines (RILs) derived from a cross between a susceptible cultivar ‘Rio Blanco’ and a resistant germplasm IDO444. HTAP resistance was evaluated for both disease severity and infection type under natural infection over two years at two locations. The genetic linkage maps covering almost the whole genome with an average density of 6.7 cM per marker were constructed using 484 markers including 96 SSRs, 384 DArTs, two STSs from semidwarf genes Rht1 and Rht2 and another two markers for low-molecular-weight glutenin subunits of seed storage protein. QTL analysis detected a total of eight QTLs significantly associated with HTAP resistance to stripe rust with two on chromosome 2B, two on 3B and one on each of 1A, 4A, 4B and 5B. QTLs on chromosomes 2B and 4A were the major loci derived from IDO444 and explained up to 47% and 42% of the phenotypic variation, respectively. The remaining five QTLs had relatively smaller effects with each accounting for 7 to 10% of the trait variation and were detected in part of the data sets. Of these minor QTLs, the resistant alleles at both QYrrb.ui-3B.1 and QYrrb.ui-4B derived from Rio Blanco and reduced infection type only. The resistant alleles at the remaining three QTLs, QYrid.ui-1A, QYrid.ui-3B.2 and QYrid.ui-5B, were all derived from IDO444 and reduced either infection type or disease severity. Markers linked to 2B and 4A QTLs should be useful for selection of HTAP resistance to stripe rust.
Agid:
56271
Handle:
10113/56271