Cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) cause losses estimated at US$1 billion every year worldwide, placing farmers at risk of food insecurity, according to the Nigeria-headquartered International Institute for Tropical Agriculture (IITA). CMD can lead to total yield loss, while CBSD affects root quality and renders roots unfit for human consumption and animal feed production.
IITA is spearheading the project in five countries — Kenya, Malawi, Mozambique, Tanzania and Uganda — in collaboration with a national agricultural research institution in each nation.
“Cassava is a very important crop in tropical countries. More than 800 million farmers grow cassava as their staple food in the tropics, including Africa.”
Leena Tripathi, International Institute for Tropical Agriculture (IITA)
The countries are sharing their top five varieties resistant to the diseases as part of a project called New Cassava Varieties and Clean Seed to Combat CBSD and CMD (5CP). The project, which is funded by the Bill and Melinda Gates Foundation, began in 2012.
The first consignment of 19 varieties in the form of plantlets or laboratory-created small plants were released last month (14 March) by Genetics Technologies International Limited (GTIL), a tissue culture-based laboratory in Kenya. According to GTIL, each of the five countries received 300 plantlets of a variety.
Six more varieties are undergoing mass multiplication and will be shared later, says Leena Tripathi, IITA country representative for Kenya. .
“Cassava is a very important crop in tropical countries. More than 800 million farmers grow cassava as their staple food in the tropics, including Africa,” says Tripathi.
Edward Kanju, 5CP project coordinator for Kenya, says cassava has a potential for commercialization to improve food security.
“We are aware that cassava has been identified to be one of the crops that can be used to mitigate climate change and many [African] countries are embarking on cassava research and production,” he says.
Kanju notes that each of the five countries will evaluate 20 new cassava varieties to identify those well adapted to local conditions and are acceptable to local farming communities.
The project will pilot in Tanzania a seed certification system for cassava to ensure that farmers grow only disease-resistant varieties, adds Kanju.
“Most of the cassava growing countries don’t have any official seed certification scheme. We want to try that in Tanzania” he says.
Simon Gichuki, the coordinator of the biotechnology centre at the Kenya Agricultural Research Institute, says: “There are other supportive projects such as virus-resistant cassava for Africa (VIRCA) looking at providing transgenic solutions to both diseases using biotechnology tools”. VIRCA is being undertaken in Kenya and Uganda.
Daniel Karanja, a plant pathologist at the Kenya branch of CABI, a worldwide organisation that addresses problems of agriculture and the environment, encourages farmers to adopt simple farm practices that would reduce the spread of the diseases.
Karanja adds that quarantine and legislation should be followed when sharing resistant varieties across countries to avoid introducing new strains of the diseases.
This article has been produced by SciDev.Net's Sub-Saharan Africadesk.