Q&A with Maria Andrade: Breeding nutritious sweetpotatoes that farmers and families love

Maria Andrade, Leader for Sweetpotato Breeding in Africa for the International Potato Center (photo: Isabel Corthier/CIP)

Orange-fleshed sweetpotato breeder and World Food Prize winner Dr. Maria Isabel Andrade loves sweetpotato and embraces the challenge to develop climate-resilient varieties to help smallholder farmers around the world. Recently, she sat down with CIP communication specialist Vivian Atakos to talk about her work.

Q: What do you love most about sweetpotato?

Maria Andrade (MA): I love sweetpotato very, very much because all those attributes that sweetpotato bring along. One it is very easy to plant. It’s very easy to grow. And under harsh conditions where no other crop can survive sweetpotato can make it. It outranks most staple crop in vitamins, minerals, fiber, and  also protein content. Sweetpotato is a true nutritional powerhouse. Only one small root, about 120 grams, meets the daily vitamin A needs for a  young child.

Q:  How many colors do sweetpotatoes come in? Why is the color important?

MA: Yes, it comes in many colors, orange, cream, and white. At the moment we are also selecting for purple fleshed because they are high in antioxidants which help improve the immune system. But I love the orange ones. You will always see me dressed in orange. As a breeder I need to promote my  variety. You promote it at home. In the field you paint your car orange. You paint your kiosk orange. In a place like Mozambique’s countryside where the literacy rate is very low the color really helps us (promote the nutritional benefits). Women can pick it out because they know the deeper the orange the more vitamin A that is in it and they know that’s better for their children.

Q: This crop is unique, because as the entire plant can be used. Can you tell us about this?

MA: Yes, indeed, it’s very versatile. With sweetpotato nothing goes to waste. You can eat the roots and leaves. The vines are used fast planting material and the vines left in the field after the harvest can be used for animal feed.

Q: How does sweetpotato help to grow farmer resilience?

MA: Sweetpotato can save thousands of people from hunger. In an emergency setting it can be used as a disaster recovery crop. After Cyclone Idai hit Mozambique, for example, the first thing people started looking for was sweetpotato vines. When you plant these, within two months you have the leaves to eat. In three months, you also have the roots to eat. It also grows when other crops fail. In 2013, we had a drought in the southern part of Mozambique and in the field one of the few crops found was sweetpotato. When some rains fell farmers planted maize and sweetpotato at the same time. But there were no additional rains and all that maize was gone but the sweetpotato was still there. Of course, under the drought the yields  are less but the farmers will harvest the leaves and also will harvest some roots.

Sweepotato is the ideal food security crop in the aftermath of an emergency or disaster. Within two months of planting, people can eat sweetpotato leaves and in three months the roots. (photo: Isabel Corthier/CIP)

Q: Are there some specific traits that really make sweetpotato a climate-smart crop?

MA: Southern Africa is a region of surprises. It has floods and droughts. We really need to be looking at varieties that can withstand such extremes. With drought we look into so many traits like how they survive, how they spread on the ridge, how is it is it is affected by early season drought, and nutrition. Of course, we also look at yields because there is a tremendous genetic variability in sweetpotato, concerning the vine’s survival.

There is one variety from Georgia in the United States called Resisto. The vines are very small size and when drought hits, they’re the first to die . That was one very early indication to me that if I want my variety to survive, I need to look into the diameter  of the vine, because the stronger the vine the more they are able to survive. If I want them to withstand  very dry conditions, I need to look into the sproutability of the roots, because in the African farming system farmers usually leave the roots under the ground. Those roots sprout with the first rains.  And, of course, taste is very important. It doesn’t matter what you choose but it does not taste very well the farmers will not accept it.

Q: Speaking of farmers, why is it important to get the farmers’ input early on in the breeding process?

MA: It is very important because the farmers are the producers, but they are also the consumers. We call them the end users. Incorporating their thoughts earlier in the breeding process is very important. It allows us to make sure that the variety that is released in four years reflects their needs.

One of the conditions with the excellence in breeding platform is that we get input from many stakeholders to make sure that what becomes a variety is adopted into the market successfully.

That is why involving the farmers, the youth, physiologists, agronomists, breeders very early to really discuss  the product profile. Then the breeders will understand what are the traits that the farmers and all the other stakeholders are looking for. Then the breeders will start to design how to conduct the breeding program, to incorporate in the breeding program  the needs of all the stakeholders including the farmers.

Q: Let’s change gears a bit and look at speedbreeding, it’s a term that is being used more and more in the breeding world, and I understand that speedbreeding has worked to cut the time in developing new varieties almost into half. Can you explain how this works?

MA:  Sweetpotato breeding in the past took eight years to produce a result. And with speedbreeding we cut this process in half, four years. With the accelerated breeding scheme instead of increasing the amount of vines from the seedling nursery to plant at observational trial in one site, the vine is multiplied to produce 12 cuttings and then take it at a very early stage to four different sites for evaluation. This is the first evaluation at observation trial instead of evaluation in one site.

If it’s drought we’re looking at will take it to one site at least with extreme drought. But, if we go to central Mozambique drought is not the problem, but we have a problem of viral disease. So, we screen for both of these traits simultaneously. It’s a process called speedbreeding because you have to do a lot of work fast to be able to increase the material to evaluate in a short period of time. This allows us to be able to release a variety in four years.

Q: In closing, what has you excited about the future of sweetpotato?

MA: You know I think sweetpotato has a great future at the moment, more than ever before, because we are into a new project  called SweetGAINS (Sweetpotato Genetic Advances and Innovative Seed Systems). With SweetGAINS we are working towards modernizing breeding operation in-situ, to deliver what we call genetic gain directly at the smallholder farmer level.

It doesn’t matter how many  varieties you produce at the moment but whatever we produce must have an impact at the farmer level. And this variety should achieve an adoption rate of at least five percent above that of the most popular variety in a given environment—farmers, field, and the site. What is very exciting about SweetGAINS is that we are including the national program of at least four countries. They will get the training and capacity building to be able to deliver  the product.

I’m really learning a lot with this new project. We are looking into all these genetic variations, the general combining ability to be able to select parents that will go back into the crossing block for  hybridization, to produce top varieties. This is quite new, it’s a new era for sweetpotato in Africa and Asia.

Visit us on SoundCloud to listen to the SweetGAINS podcast featuring Maria Andrade and other scientists modernizing plant breeding.

 This interview has been edited for length and clarity.