BackgroundTef (Eragrostis tef), an indigenous cereal critical to food security in the Horn of Africa, is rich in minerals and protein, resistant to many biotic and abiotic stresses and safe for diabetics as well as sufferers of immune reactions to wheat gluten. We present the genome of tef, the first species in the grass subfamily Chloridoideae and the first allotetraploid assembled de novo. We sequenced the tef genome for marker-assisted breeding, to shed light on the molecular mechanisms conferring tef’s desirable nutritional and agronomic properties, and to make its genome publicly available as a community resource.ResultsThe draft genome contains 672 Mbp representing 87% of the genome size estimated from flow cytometry. We also sequenced two transcriptomes, one from a normalized RNA library and another from unnormalized RNASeq data. The normalized RNA library revealed around 38000 transcripts that were then annotated by the SwissProt group. The CoGe comparative genomics platform was used to compare the tef genome to other genomes, notably sorghum. Scaffolds comprising approximately half of the genome size were ordered by syntenic alignment to sorghum producing tef pseudo-chromosomes, which were sorted into A and B genomes as well as compared to the genetic map of tef. The draft genome was used to identify novel SSR markers, investigate target genes for abiotic stress resistance studies, and understand the evolution of the prolamin family of proteins that are responsible for the immune response to gluten.ConclusionsIt is highly plausible that breeding targets previously identified in other cereal crops will also be valuable breeding targets in tef. The draft genome and transcriptome will be of great use for identifying these targets for genetic improvement of this orphan crop that is vital for feeding 50 million people in the Horn of Africa.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-581) contains supplementary material, which is available to authorized users.

The present study contributes to a better understanding of major palynological trends in Impatiens, one of the largest genera in angiosperms, and evaluates the phylogenetic usefulness of pollen morphological characters in the genus. The pollen morphological diversity of 115 Asian species of the genus was investigated using light microscopy and scanning electron microscopy and analyzed in a phylogenetic framework using Bayesian inference and Bayesian posterior character mapping as well as parsimony character optimization. Despite the rather young age of Impatiens and its extremely rapid radiation, a striking palynological variability could be observed. The ancestral pollen type in Impatiens is a triangular, tri–aperturate pollen grain with reticulate sexine ornamentation, which subsequently evolved into the main Impatiens pollen type: a 4–aperturate, rectangular pollen grain with a reticulate sexine ornamentation. The most recently diversified Asian clades are characterized by several reversions from 4–aperturate to 3–aperturate and changes in sexine ornamentation from reticulate to microreticulate sexine ornamentation. Also differences in pollen view can be observed amongst the most recently diversified Asian lineages ranging from circular, quadrangular, elliptic to sub–elliptic and rectangular. Although some pollen morphological characters seem to be homoplasious, others help to improve the resolution of some phylogenetically problematic lineages in the genus.