Banana has revealed the secrets of its 520 million bases. Two French research organizations, CIRAD and CEA-Genoscope, with funding from the National Research Agency (ANR), have just finished, in two years, sequencing the species Musa acuminata which is a component in every edible variety (dessert and cooking bananas). This work is a huge step towards understanding the genetics of and improving banana varieties, and was done within the framework of the Global Musa Genomics Consortium.
An essential varietal improvement tool
Bananas are vitally important for the food and economic security of more than 400 million people in southern countries, but are under constant pressure from a range of parasites. That pressure is particularly high in plantations producing the “export” bananas we find in our supermarkets. It is therefore crucial to develop new, more resistant varieties, although this is a complex operation given the very low fertility of cultivated banana varieties.
The newly available genome sequence provides access to each and every one of the plant’s genes – more than 36 000 of them – and to their position on its eleven chromosomes. This knowledge will make it much easier to identify the genes responsible for characters such as disease resistance and fruit quality. Lastly, it will be a vital tool for improving banana varieties using the many genetic resources available worldwide.
A new view of genome evolution
Banana is the first plant in its botanical class (monocotyledons), alongside cereals, for which whole genome sequencing (anchored on the chromosomes) has been achieved. As such, it is a highly valuable reference for use in studying genome evolution. For instance, researchers have been able to establish that banana has seen three episodes of complete genome duplication, independent of those seen in grasses. While most of the genes resulting from such events are generally lost, some persist and lead to the emergence of new biological functions. Researchers have already identified certain regulatory factors (transition factors), which are particularly numerous in banana and contribute to important processes such as fruit ripening.
This work was conducted with financial support from the French National Research Agency (ANR).
The banana genome sequence is freely available on the following website: http://banana-genome.cirad.fr.
- Genome sequencing could boost African banana production (scidev.net)
- Banana genome sequence will aid crop improvement (thehindu.com)