Bioversity International: research for development in agricultural and tree biodiversity

Take a virtual tour of the Mbarara field collection of banana diversity, Uganda

18 Mar 2016

Join Bioversity International researchers Deborah Karamura and William Tinzaara on a virtual tour of the East and Central Africa Musa Germplasm Collection in Mbarara, Uganda. They explain why we need to better understand and use the genetic diversity contained in the world’s favourite fruit in order to secure its future, and the food security and livelihoods it brings to millions of people. 

Standing above 1400 metres, the Mbarara field collection of banana germplasm enjoys breathtaking views of the surrounding agricultural landscape, much of which is dedicated to cultivating the ubiquitous banana. In Uganda, where the collection is situated, as in many parts of East and Central Africa, smallholder farming production and family diets are highly dependent on the banana.

East and Central Africa is considered a secondary centre of diversity for bananas – especially highland bananas – yet production is facing many threats, such as changes in the climate, declining soil fertility and pest and disease outbreaks. Exploiting the diversity contained within this banana field collection is essential to help farmers adapt to these threats.

Bioversity International researchers Deborah Karamura and William Tinzaara take us on a virtual tour of the collection:

William: Many people around the world think bananas only come in one shape and colour due to the enormous international success of the familiar yellow Cavendish they see in their supermarkets – this one variety of banana accounts for arounds 40% of global banana production. But this is such a small part of the banana story. When you look around this collection, you can see many different varieties of bananas, through the differences in colours and shapes of the fruits, bunches, buds, leaves and stems. And then there are the differences you cannot see – the genetic traits that are contained inside that give each variety a unique set of qualities that affects how it grows, its resistance to pests and diseases, its taste, its nutritional properties, and so on.

Deborah: The collection has more than 400 samples which have come from many different parts of the globe. The majority have come through the Bioversity International Musa Transit Centre in Belgium - the world’s largest collection of banana germplasm. We also have varieties that have been donated to us, or have come from collecting missions, where we go and pick different kinds of bananas, especially from the East and Central Africa region, from countries like Tanzania, Kenya, Congo, Burundi and Rwanda.

William: What is really interesting is that with the new challenges farmers are facing in growing bananas, they are looking again at diversifying the kind of bananas that they grow, looking for those that can tolerate the new growing conditions. In the past, you would visit the farms around the area, and you would see between 30-50 varieties of bananas growing on a smallholding. They would grow some to sell and some to use, such as in traditional recipes. But this number has really declined. We have carried out surveys that show that the number of varieties has dropped down from an average of 40 varieties on a single farm to an average of 7 in a period of 20 years.

Deborah: On a recent visit with William to Bushenyi, which is a district in Western Uganda, to study which banana varieties farmers were growing, I was really surprised to find that across the area, only four to six varieties are being grown. This means that the farmers are exposing themselves to a high risk of losing an entire crop through extreme weather conditions or a disease outbreak, and that this will bring genetic erosion – if we do not use crop genetic diversity and the options it brings, we lose it.

William: In the past, farmers would travel long distances to see their relatives at the start of the growing seasons and to see if they had ‘new’ varieties. In this way they would collect them and plant them near their house to study them, and if they liked them, they would grow them on their farms. This does not happen now. Instead when a farmers loses a banana variety, for example from a disease outbreak, they just stop growing it, rather than look for a replacement variety. This is why having collections such as that held here is so important, both now and in the future, in addition to training farmers, extension and researchers about how to use banana diversity for a food-secure future.

Deborah: We need all these different sorts of varieties simply because they give us management options, for example, some can grow well in poor soils, some are resistant to certain diseases and some are more nutritious. Working with our partners in Uganda through the National Agricultural Advisory Services and with farmers in the area, we are able to systematically evaluate these materials when we want to popularize some in farmers’ fields to better understand their genetic diversity, and the socioeconomic options that diversity brings.

Through the National Agricultural Research Organization, we carry out agronomic evaluation to study the varieties in terms of differences in attributes like yield, bunch size, and resistance to pests and diseases. Another important activity is that we train stakeholders in skills and tools for data collection and analysis, characterization of banana genetic diversity, and developing protocols to manage the collection.

William: The work we do with farmers to get their feedback on preferences is really important. For example, we may get really excited about the potential of a new improved variety that has a high resistance to a certain disease and grows vigorously but it is only when we test it with farmers that we learn how it behaves in different environments and farming conditions. Another consideration is taste and suitability for traditional dishes and cooking methods. There is no point pushing an improved variety that the farmers do not want to grow, or that the people do not want to eat.

Deborah: Since 1927, several banana field collections in Uganda have been lost largely due to inadequate funding and civil strife. The Ministry of Agriculture, Animal Industry and Fisheries together with the National Agricultural Research Organization (NARO) have always been keen to support collections as they form core units of crop research and development programmes and are sources of planting materials for the country’s farmers. The collection expanded its scope to become a regional collection in 2007, to support crop improvement programmes and to serve as a backup for national collections across East and Central Africa. 

This week, Cristián Samper, Chair, Board of Trustees, Bioversity International, (pictured centre, bottom photo) visited the Mbarara Collection as part of a trip to Uganda where he also visited other research sites. He commented that "We can be proud of our team and our mission, which is critical to improve the livelihoods of people in countries like Uganda."

This work is carried out through Bioversity International's Effective Genetic Resources Conservation and Use Initiative and the CGIAR Research Program on Roots, Tubers and Bananas.

All photos were taken at the East and Central Africa Musa Germplasm Collection in Mbarara, Uganda and should be credited: Bioversity International/N. Capozio
(with the exception of the bottom photo which should be credited C. Samper)