Sequenced – a banana genome

Looking at a banana you might ask, how did this monoculture, a cultivar derived from only one seed become a major source of food (eighty-five percent of banana production is consumed locally in tropical and sub-tropical countries), and is a major source of income for over 500 million people.  You might then fairly come to the realisation a banana is a staple food and food security issues abound.

With a little research the prime issues surface as: Pests and diseases have gradually adapted to the cultivar that is predominating in banana production; the two main diseases at the moment are the Panama Disease and the Black Sigatoka Disease. The Black Sigatoka is now all over the world and the Panama Disease – a new type – is in Asia only, but it will probably extend to other areas.

The potential solution is reported by DW and according to Zulfikar Abbanyin: “France’s CIRAD – a centre for agricultural research for development – and the National Research Agency (ANR) say they have sequenced the DNA of banana. Led by CIRAD’s Angélique D’Hont, the researchers were able to map the genome of a wild Asian strain called Musa acuminate – a component in every edible variety of bananas. They say their work is an important step toward understanding the genetics of the crop – and toward improving varieties and strengthening them against fungus and pests. But Angélique D’Hont says CIRAD is focused on cross-breeding rather than genetically modifying bananas”.

So, how can the findings help farmers and cultivators beat the pests?

The work has the objective to breed new banana varieties – new cultivar. CIRAD say this type of breeding is quite complicated, as bananas have to produce sterile fruit – that is, fruit without seeds to make them edible. And to make new bananas you have to perform crossbreeding, so you need a fertile plant. So far CIRAD has sequenced one banana genome type and have identified 36,000 genes and the exact position of these genes on the chromosome. And, more work is required to find the specific genes that confer resistance to the main diseases and also for conferring good fruit quality.

Now comes the interesting question: Will they want to genetically modify…? No.

The answer comes in the term transgenesis – to modify current cultivar and then attempting to breed new cultivar by crossing different cultivar with different types of resistance. This breeding approach is possible because of knowing which gene and which genotype has the important gene that will help the breeder to create new cultivar by classical breeding techniques.

CO2Land org can see the approach to protect this important food source as most important and the other value added aspects for the environment become apparent including the reduced need for using pesticides and reducing cost for agriculture.  But a surprising barrier to the adoption of the new cultivar is the process for transporting and conserving bananas for export. The fact is current refrigerated means of transport are developed for one cultivar, the Cavendish banana. An interesting case of need for adaptation to changed needs, and the change will all come down to the money- Yes!