Decoding our daily bread

摘要

The bread wheat genome presents a significant challenge to researchers. At 17 gigabases, it is about six times the size of the human genome, and it is hexaploid, meaning that it contains six sets of chromosomes, which derive from three different genomes. So why bother to sequence such a difficult genome? Wheat is arguably the most important plant to humans. Bread wheat (Triticum aestivum) is the worlds most widely grown crop, covering more than 200 million hectares of land1 throughout temperate, Mediterranean-type and subtropical regions of both the Northern and Southern hemispheres. Although total production of wheat - 681 million tonnes in 2011 (ref. 1) - is slightly lower than that of maize (corn) and rice, wheat is the primary carbohydrate and protein source for the world's population. For this reason, researchers around the world are tackling the challenge of the plant's genome. On page 705 of this issue, Brenchley et al. present a detailed analysis and assembly of wheat gene sequences that will provide a key resource for crop scientists.