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Abstract Hessian fly (HF;Mayetiola destructorSay) causes severe damage to wheat (Triticum aestivumL.) worldwide. Several resistance genes have been identified in wheat and wild relatives; however, HF populations are under strong selection pressure and evolve rapidly to overcome resistance. To ensure the availability of resistance sources, HF‐resistant germplasm KS18WGRC65 (TA5110, Reg. no. GP‐1042, PI 688251) was developed by Wheat Genetics Resource Center at Kansas State University as a breeding stock that carries resistance geneH26fromAegilops tauschiiCoss. KS18WGRC65 is a cytogenetically stable, homozygous, BC3F3:6line derived from the cross betweenAe. tauschiiaccession KU2147 and hard red winter wheat recurrent parent ‘Overley’. KS18WGRC65 exhibited no penalty for yield or other agronomic characters, making it a suitable source of HF resistance for wheat breeding.
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Cloning of the broadly effective wheat leaf rust resistance gene Lr42 transferred from Aegilops tauschii
Abstract The wheat wild relativeAegilops tauschiiwas previously used to transfer theLr42leaf rust resistance gene into bread wheat.Lr42confers resistance at both seedling and adult stages, and it is broadly effective against all leaf rust races tested to date.Lr42has been used extensively in the CIMMYT international wheat breeding program with resulting cultivars deployed in several countries. Here, using a bulked segregant RNA-Seq (BSR-Seq) mapping strategy, we identify three candidate genes forLr42. Overexpression of a nucleotide-binding site leucine-rich repeat (NLR) gene AET1Gv20040300 induces strong resistance to leaf rust in wheat and a mutation of the gene disrupted the resistance. TheLr42resistance allele is rare inAe. tauschiiand likely arose from ectopic recombination. Cloning ofLr42provides diagnostic markers and over 1000 CIMMYT wheat lines carryingLr42have been developed documenting its widespread use and impact in crop improvement.
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- PAR ID:
- 10381712
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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