At 11:00 a.m. on Tuesday, March 17, farmers and consumers from cassava-growing districts gathered in a hall at the Rubona Agricultural Research Station in Huye District for a sensory evaluation of six biotech cassava varieties. A researcher explained the scoring scale for both boiled tubers and Ugali, ranging from 1 to 5. ALSO READ: Cassava farmers wary as viral disease ravages crops A score of 1 represents “very bad”, 2 “bad”, 3 “fair”, 4 “good”, and 5 “very good”. Before the evaluation began, participants were asked how often they consume cassava. They were then invited to assess various attributes of the samples, including colour, smell, taste, appearance and aroma. The six biotech varieties were presented alongside two non-genetically modified varieties to allow for comparison. After the assessment, participants were asked to select their most preferred variety as well as the one they liked least. These are genetically modified (GMO) cassava varieties that are resistant to Cassava Brown Streak Disease (CBSD), locally known as Kabore, and Cassava Mosaic Disease (CMD), which have devastated the crop for years. The varieties have undergone trials over the past six years. ALSO READ: How three biotech crops could help Rwandan farmers curb losses In 2024, Rwanda officially enacted a new biosafety law, establishing a legal framework for the safe handling, transfer and use of genetically modified organisms (GMOs). The development of these cassava varieties progressed through several phases following approval from the Rwanda Environment Management Authority (REMA). The current phase—sensory evaluation, dubbed “Eating is Believing”—follows the transition of the varieties from confined trials to open-field testing. Why does this matter? Sensory evaluation involves testing cassava using human senses, while “Eating is Believing” reflects the idea that people are more likely to accept the varieties after tasting them. The results of this evaluation will inform the decision whether some of these varieties can be added to the list of approved seed varieties by the Rwanda Inspectorate, Competition and Consumer Protection Authority (RICA). “These are good varieties with higher yields. The taste is also very good, based on my own evaluation. They are suitable for producing cassava flour, and their key advantage is resistance to diseases such as Kabore,” said Cesalie Kantarama, a cassava seed multiplier from Muhanga District. ALSO READ: Rwanda finally passes law on GMOs: What next? Speciose Mujawamariya, a farmer and seed multiplier since 2007, said: “When cassava is affected by Kabore disease, we incur losses from labour and agro-inputs through to harvest.” Cassava, Rwanda’s third most consumed staple crop, has suffered significant yield losses due to Cassava Brown Streak Disease. National incidence rose from 18.5% in 2012 to 69% in 2014. The disease renders roots inedible and has contributed to a 73% drop in cassava yields and a 40% decline in export earnings between 2016 and 2017. Approximately 200,000 hectares in Rwanda are dedicated to cassava cultivation, making it the country’s third most important crop after bananas and sweet potatoes. Due to Kabore, annual cassava production fell sharply from 3.3 million tonnes in 2012 to just about 657,000 tonnes in 2013, before recovering slightly to 900,000 tonnes in 2014. In response, Rwanda’s Agri-Biotech Programme has been focused on developing virus-resistant varieties to restore productivity and strengthen food security. ALSO READ: Inside Rwanda’s new Rwf13bn agri-biotech programme Since 2021, the country has made significant progress in evaluating genetically modified cassava through confined field trials conducted at Rwanda Agricultural and Animal Resources Board (RAB) stations in Rubona, Mututu and Musenyi. An expansion at Rubona in 2025 enabled additional multiplication of cuttings. Seven transgenic cassava clones developed by the Donald Danforth Plant Science Center under the VIRCA project have been tested for resistance to Cassava Brown Streak Disease and Cassava Mosaic Disease. Researchers at RAB said the findings indicate that these varieties have agronomic traits comparable to conventional cassava, strong resistance to CBSD, and high yield potential. The new varieties were engineered using RNA interference technology targeting viral coat proteins responsible for CBSD viruses. Athanase Nduwumuremyi, Senior Research Fellow and Roots and Tubers Programme Coordinator at the RAB, said that following consumer evaluation, the GMO cassava varieties will be submitted to RICA for approval before mass multiplication and commercial distribution. Cassava is a major crop for food security in Rwanda. These varieties, developed over six years, can yield between 35 and 40 tonnes per hectare, he said. We will submit them to RICA for inclusion on the approved seed list. Meanwhile, we have begun seed multiplication to supply model multipliers and farmers, who will further distribute them. Farmers also can name the new varieties,” he said. He added that farmers could begin accessing the new varieties as early as next year. From October 2024 to October 2029, Rwanda is implementing a new programme, supported by over $9.8 million from the Bill & Melinda Gates Foundation, to introduce three biotech crops for cultivation. A centre of excellence in crop biotechnology is also set to be established at the Rubona Research Station under a new five-year project led by the Ministry of Agriculture and Animal Resources. The centre will equip Rwandan scientists with advanced skills in genetic transformation, genome editing, molecular diagnostics and biosafety. The programme aims to strengthen Rwanda’s capacity to develop, regulate and deploy improved crop varieties tailored to national needs, thereby enhancing food security, climate resilience and sustainable agricultural growth. Initially, the project will focus on three priority crops critical to Rwanda’s food security: potato resistant to late blight fungus, cassava resistant to brown streak virus, and banana resistant to bacterial wilt. For maize, researchers are developing drought-tolerant varieties as well as those resistant to pests such as fall armyworm and stem borer.
