Better Bananas with Biotech

Dr. Leena Tripathi is the Principal Scientist in Plant Biotechnology at the International Institute of Tropical Agriculture (IITA), Kenya. She is Deputy Director of East Africa Hub and Country Representative of IITA-Kenya.

Learn more about her research that has the potential to prevent billions of dollars in crop losses every year for family farmers in Africa.

 What inspired you to be a scientist in the first place?

I studied science so I could use what I learned to bring people health or food security solutions.

During my PhD studies, I focused on developing pest resistant varieties increasing food production which meant being able to provide solutions to farmers’ problems. After receiving my PhD, I focused more on staple food crops and asked myself “what are the farmer’s challenges around losses during the production of these crops? How can I use cutting edge science to provide the solution to those problems?”

What research project are you working on right now?

My research currently focuses on bacterial wilt disease in banana. I also work on some of the viral diseases like banana bunchy-top virus and banana streak virus. My group is also focusing on nematodes because they are one of the most significant pests for bananas.

The east Africa region is one of the major banana growing areas; I will give the example of Uganda. It is the largest producer of bananas in Africa and globally is the third largest producer but in terms of consumption, Uganda is number one. Banana is the staple food for Ugandans so it is more like rice, wheat and corn for other countries.

This bacterial wilt disease’s impact is quite drastic. Once the pathogen is in the field, it wipes out the banana from the field very quickly—within a few months you will see all the banana plants wilted. The disease also causes the premature ripening of the fruit so even though the diseased plant might produce some fruits, they are not edible.

Since the losses are absolute, you can see that this is a very important problem to fix. In the past, the economic losses were estimated between $2 to $8 billion in this region.

If every farmer could grow the varieties you are working on, what would the impact of that be?

We started working on developing the resistant varieties because all of the common cultivated varieties that the farmers are growing in Africa are susceptible to this disease. The only thing that can withstand the disease is some wild-type bananas, but they are small and seeded so the farmers don’t grow them.

The resistant varieties we are researching might be the best solution for this disease because there is no resistant variety and no chemical control for it. Basically, once the disease is in the field, the only remedy that is available is to cut down the diseased plants and leave the field fallow for some time before the bananas can be grown in that field again. This is a very difficult, laborious process for the farmers and in Africa, the smallholder farmers can’t afford to leave the field fallow for a few months before they can replant the bananas. That is why the resistant varieties are the most economical and sustainable solution for controlling the disease and that’s why, in partnership with The National Agricultural Research Organisation (NARO) in Uganda, we started developing transgenic banana resistant to bacterial wilt disease.

We feel that once this variety is ready to release, farmers will benefit from it because millions of their families are affected by this bacterial disease and if they were to start growing these resistant varieties, it could help them.

Are there any other ways agricultural innovation can make life better for family farmers?

We have started applying gene editing techniques into our work and we established a system for gene editing in our lab which is working well for bananas. We targeted banana streak virus first.

Banana streak virus is a big challenge in banana breeding because it integrates into the genome. It sits silently there until the plant gets stressed during unfavorable conditions like a rise in temperature or a period of drought.

In collaboration with University of California, Davis, my group has recently developed a strategy where we used genome editing to knock out that integrated virus. Now we are improving the genetic germplasm which breeders use in the breeding program, so they can develop better hybrids.

Her team works with plant biotechnology with focus on transgenic and genome editing for crop improvement in banana to benefit family farmers in Africa. They also use gene editing technology to develop bacterial and fungal disease resistant varieties.