Nicotiana tabacum, as a model plant system, has played important roles in the development of molecular plant biology. Recently, because of its active metabolites, it has attracted more attention in biochemistry and biotechnology. However, the tobacco genome is large and challenging to sequence because it is an allotetraploid, formed by hybridization of diploid parents N. sylvestris and N. tomentosiformis. Although several groups have already released their draft genomes, production of a genome sequence with sufficient quality is still difficult and challenging.

Here we report on a tobacco genome sequence of the HongDa cultivar, which has been produced by the combination of BAC-to-BAC and whole genome shotgun technologies. The final assembly achieved an N50 size of 1.61 Mb and enabled the anchoring of 70 % of the genome to the chromosomes, which is a big improvement compared with most of the current tobacco genomes. Meanwhile, 71,456 gene modes were annotated, which is also more comprehensive than other versions.

In order to support usage of tobacco genomic resources, relative data and a number of tools have been made available by the China Tobacco Genome Database developed by our group. These include, but are not restricted to, genome browser, transcriptome expression level, metabolism and many useful analysis tools (BLAST, WEGO, Primer3 etc.).