RT Journal Article
SR Electronic
T1 Exploiting the <em>ZIP4</em> homologue within the wheat <em>Ph1</em> locus has identified two lines exhibiting homoeologous crossover in wheat-wild relative hybrids
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 142596
DO 10.1101/142596
A1 María-Dolores Rey
A1 Azahara C Martín
A1 Janet Higgins
A1 David Swarbreck
A1 Cristobal Uauy
A1 Peter Shaw
A1 Graham Moore
YR 2017
UL http://biorxiv.org/content/early/2017/05/26/142596.abstract
AB Despite possessing related ancestral genomes, hexaploid wheat behaves as a diploid during meiosis. The wheat Ph1 locus promotes accurate synapsis and crossover of homologous chromosomes. Interspecific hybrids between wheat and wild relatives are exploited by breeders to introgress important traits from wild relatives into wheat, although in hybrids between hexaploid wheat and wild relatives, which possess only homoeologues, crossovers do not take place during meiosis at metaphase I. However, in hybrids between Ph1 deletion mutants and wild relatives, crossovers do take place. A single Ph1 deletion (ph1b) mutant has been exploited for the last 40 years for this activity. We show here that selection of chemical induced mutant lines possessing mutations in TaZIP4-B2 exhibit high levels of homoeologous crossovers when crossed with a wild relative. Exploitation of Tazip4-B2 mutants rather than mutants with whole Ph1 locus deletions may improve introgression of wild relative chromosome segments into wheat. Such mutant lines may be more stable over multiple generations, as multivalents causing accumulation of chromosome translocations are less frequent.Key message Exploiting the ZIP4 homologue within the wheat Ph1 locus has identified two wheat mutants through a non-GM route, which can be exploited as an alternative to the Chinese Spring ph1b mutant in wheat introgression strategies.