NextGen Cassava Fellow Leah Nandudu is applying her passion for plant science to improve lives for smallholder cassava farmers around the world. The NextGen Cassava team sat down with Nandudu, a doctoral student in plant breeding and genetics, to learn more about her research and her impact.
Why did you enter the field of plant breeding and specifically cassava?
I am passionate about plant breeding because it’s my way of contributing towards humanity. This passion developed from the first time I interacted with small-scale farmers who, despite all their efforts, attain low yields that render them vulnerable to food and economic insecurity. Plant breeding can provide high yielding, disease resistant and biofortified food crops that can improve the livelihoods of small-scale farmers whose efforts maintain food supply chains around the world. I am interested in cassava because it’s a crop that is crucial for small-scale farmers in sub-Saharan Africa yet it’s being ravaged by cassava brown streak disease. The most sustainable way of controlling this disease is breeding for resistance.
What keeps me going in my pursuit to improve cassava resistance against cassava brown streak disease is knowing that the work I do puts a meal on someone’s plate and money in their pockets.
What's the focus of your research?
Cassava (Manihot esculenta Crantz) is a mainstay for both the rural and urban populace in tropical Africa. Its roots and leaves are exploited in various ways for both food and non-food uses of economic value. Cassava is also drought tolerant with the ability to yield in marginal soils, making it a climate resilient crop. Unfortunately, diseases like cassava brown streak disease (CBSD) constrain cassava production thus threatening food and economic security for millions in sub-Saharan Africa.
Why is CBSD prevalent in East and Central Africa?
CBSD started in the coastal regions of East Africa in the 1930s and was known to thrive only at altitudes below 1000 meters above sea level (masl). At the time, CBSD was not considered a threat to cassava production because of its geographical restriction so breeders concentrated their efforts on breeding for resistance against cassava mosaic disease (CMD) that was wide- spread and caused famines.
To save cassava from CMD, breeders decided to make crosses between East African local varieties and wild relatives of cassava. Unfortunately, cassava varieties that were resistant to CMD were susceptible to CBSD. This provided the opportunity for CBSD to evolve which led to the creation a new CBSD species that could survive at altitudes above 1000 masl. The rampant spread of CBSD was also accelerated by farmers who moved infected planting material across the region. Currently CBSD is prevalent in East and Central Africa, though scientists fear the virus could spread to West Africa, a region whose food systems depend even more on cassava.
