Tuesday, May 31, 2016 - 11:00
New Seminar Room, James Hutton Institute Errol Road, Invergowrie, DD2 5DA
Dr Sarah McKim
Dr Thorsten Schnurbusch
Leibniz Institute of Plant Genetics and Crop Plant Research(IPK)
Inflorescences of the tribe Triticeae, containing wheat (Triticum sp. L.), barley (Hordeum vulgare L.) and rye (Secale cereale L.), display a raceme-like branchless shape, and are therefore called a spike. Each spike is normally composed of spikelets arranged in two opposite rows along the main axis (rachis). Individual spikelets contain one or several florets, each producing one grain. In contrast to other grass species like rice and maize, little is known about the genetic determinants that regulate inflorescence specification in Triticeae. Genes responsible for row-types in barley (Komatsuda et al. 2007; Ramsay et al. 2011; Koppolu et al. 2013) are among the few that have been characterized so far. Here, we report on a gene in tetraploid wheat and barley containing an AP2/ERF domain that represses inflorescence branch formation. Across grass species TtBH-A1/COM2 show 100% sequence conservation within the AP2/ERF domain and a highly conserved protein coding region. Mutated forms of this gene always cause inflorescence branching suggesting a consistent role in preventing formation of any ectopic branch-like meristems in grass inflorescences.