Plant genomic triplet

People rightly bemoan the fact that you inevitably wait ages for a bus to turn up, and when it does eventually happen oftentimes several arrive at once. As with public transport, so too in the world of plant genomics. That is not to belittle the heroic sequencing efforts of those dedicated ‘gene-genies’ but a tribute to the pace of DNA sequencing that is now possible. Thus, Moon Young Kima et al. report whole-genome sequencing of Glycine soja (PNAS 107: 22032–22037, 2010), the undomesticated ancestor of G. max. Given that the genome of G. max – the commercially important soybean – has already been sequenced, you may wonder why bother with G. soja. It is because of the economic importance of G. max that it is desirable that it should be further improved, hence the search for clues to ways this could be achieved by studying its ancestor’s DNA. Xavier Argout and a large group of co-workers have recently published the genome sequence of the Criollo variety of Theobroma cacao (Nature Genetics doi:10.1038/ng.736). Theobroma cacao may be more familiar to some readers as the tropical tree that bears the fruit that contain the seeds that are used to make chocolate. It is expected that this divine knowledge – the generic name Theobroma is usually translated as ‘food of the gods’ (http://en.wikipedia.org/wiki/Theobroma) – will be used to good effect to further improve the variety that makes some of the world’s finest chocolate (http://live.psu.edu/story/50523). A second luxury food item, the woodland strawberry, has also received the sequencing treatment: Vladimir Shulaev et al. (Nature Genetics doi:10.1038/ng.740) report the genome of Fragaria vesca. Similar to G. soja, this taxon is not a major crop plant but is closely related to the hybrid F. × annassa (the garden strawberry), which produces larger fruit and superseded F. vesca in the mass-cultivation stakes about 250 years ago. But F. vesca is similar to the garden strawberry and study of its genome should help improve F. × annassa – and other members of the Rosaceae (to which the genus Fragaria belongs), and which includes many commercially important food plants such as apples and pears (http://gtresearchnews.gatech.edu/strawberry-genome/). Chocolate-coloured, strawberry-flavoured soy sauce, anyone?