Genome-wide association study of stem rust resistance in a world collection of cultivated barley
Genome-wide association study of stem rust resistance in a world collection of cultivated barley
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DOI：
10.1007/s00122-017-2989-y
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发表时间：
2018-01-01
影响因子：
5.4
通讯作者：
Steffenson, Brian J.
中科院分区：
文献类型：
--
作者：
Case, Austin J.;Bhavani, Sridhar;Steffenson, Brian J.
在5H染色体上发现了使多个PGT小种的成株茎锈病严重程度降低14-40%的QTL，该QTL可用于大麦育种。小麦赤霉病(Tritici，PGT)是大麦的一种重要病害。抗病基因Rpg1在北美已有70多年的历史，但对非洲PGT小种TTKSK(及其变种)和国内小种QCCJB无效。为了鉴定对这些Rpg1致病小种的抗性，对美国农业部-农业研究服务局国家小谷物收集中心的大麦iCore种质进行了成株抗性(APR)和幼苗对小种QCCJB和小种TTKSK、TTKST、TTKTK和TTKTT的抗性的评估。利用基于6224个单核苷酸多态标记的全基因组关联研究方法，在1H、2H、3H和5H染色体上鉴定出7个显著的抗茎锈病基因座。其中位于5H染色体71-75 cM处的11_11355和SCRI_RS_177017是最显著的标记，这两个标记可能是青海杂交稻和甘薯杂交种的遗传标记。在5H染色体上也检测到了TTKSK苗期抗性的显著标记。在5H上检测到的所有标记都不依赖于152-168 cM的RPG4/Rpg5复合体。本研究证实了11_11355基因座在小种QCCJB和TTKSK中的重要作用，并提示它可能对UG99谱系中的其他小种有效。
QTL conferring a 14-40% reduction in adult plant stem rust severity to multiple races of Pgt were found on chromosome 5H and will be useful in barley breeding.Stem rust, caused by Puccinia graminis f. sp. tritici (Pgt) is an important disease of barley. The resistance gene Rpg1 has protected the crop against stem rust losses for over 70 years in North America, but is not effective against the African Pgt race TTKSK (and its variants) nor the domestic race QCCJB. To identify resistance to these Rpg1-virulent races, the Barley iCore Collection, held by the United States Department of Agriculture-Agricultural Research Service National Small Grains Collection was evaluated for adult plant resistance (APR) and seedling resistance to race TTKSK and APR to race QCCJB and the Pgt TTKSK composite of races TTKSK, TTKST, TTKTK, and TTKTT. Using a genome-wide association study approach based on 6224 single nucleotide polymorphic markers, seven significant loci for stem rust resistance were identified on chromosomes 1H, 2H, 3H, and 5H. The most significant markers detected were 11_11355 and SCRI_RS_177017 at 71-75 cM on chromosome 5H, conferring APR to QCCJB and TTKSK composite. Significant markers were also detected for TTKSK seedling resistance on chromosome 5H. All markers detected on 5H were independent of the rpg4/Rpg5 complex at 152-168 cM. This study verified the importance of the 11_11355 locus in conferring APR to races QCCJB and TTKSK and suggests that it may be effective against other races in the Ug99 lineage.