Calibrated species trees based on trnK-matK, rbcL, and ndhF including Psathyrostachys.

Calibrated multispecies coalescent derived from three chloroplast loci trnK-matK, rbcL and ndhF of all Triticeae accessions (excluding polyploid wheats). Sequences of Brachypodium distachyon, Oryza sativa and Zea mays were included as outgroups. Posterior probability values are given for all nodes. Divergence time estimates were inferred using the secondary calibration points from Marcussen et al. [20] for the Brachypodium-Triticeae split (mean 44.44 million years ago). Node bars indicate the age range with 95% interval of the highest probability density. For the analysis Triticum monococcum and T. boeoticum, Secale cereale and S. vavilovii, Pseudoroegneria tauri and Ps. libanotica, Taeniatherum caput-medusae and Tae. crinitum, Agropyron cristatum and Agr. cimmericum were each subsumed under a single species name (Additional file 1: Table S1).