New cassava variety offers hope to farmers

Researchers at Kenya Agricultural and Livestock Research Organisation (Kalro) have developed a new disease-resistant cassava variety.

The genetically modified variety, which which was developed using modern technology is resistant to Cassava Brown Streak Disease (CBSD) and Cassava Mosaic Disease (CMD). It will be released into the market soon.

Other organisations involved in the research are Virus Resistant Cassava for Africa (Virca Plus), University of Nairobi, International Service for the Acquisition of Agri-Biotech Applications (ISAAA), International Institute for Tropical Agriculture (IITA) and several other NGOs.

Cassava is an important food crop in Kenya and performs well in the arid and semi-arid areas which make up to 80 per cent of the country's land mass area. It is the second most important staple after maize in the Coastal and Western regions. Cassava survives well during drought when very few other sources of food are available. However the two diseases have seen farmers suffer low and poor yields.

CBSD is spread between plants by white flies and by farmers who plant infected cassava cuttings. Storage roots produced by plants infected with CBSD usually develop brown lesions, making them inedible as food and animal feed.In severe infections, CBSD can result in up to 100 per cent loss of usable storage cassava root

But the CBSD resistant cassava has the potential to prevent 90 per cent crop damage and improve yield and marketable roots of cassava.

It was these challenges related to disease pandemics that compelled Kalro to seek for a reliable solution for farmers. Early August this year, a team of farmer leaders and journalists were invited to witness a verification exercise on the new cassava variety at Kalro Mtwapa and got to learn the journey so far.

As part of the journey, Prof Douglas Miano, lead scientist at Virca Plus Kenya, explains that multiple cropping cycles were conducted for more than five years followed by field tests and extensive safety studies in Kenya. An application for environmental release or open field cultivation of the CBSD resistant cassava was submitted by Kalro to the National Biosafety Authority (NBA) in 2019. Approval was granted in June 2021.

According to Miano, the next stage is now for the Kenya Plant Health Inspectorate Service (Kephis) to conduct national performance trials before the cassava variety is registered and released to farmers. And when will this be?

"I cannot give a definite date for now. But very soon," says Prof Miano.

Since 2011, the project's researchers have been growing and evaluating disease resistant cassava in three diverse locations in Kenya namely Mtwapa, Kandara and Alupe.

Dr Catherine Taracha, Director Kalro Biotechnology Centre explains the different activities in the three locations: She says Kalro Mtwapa is an experimental site with high disease incidence of both CBSD and Cassava Mosaic Disease.

Kalro Kandara hosts regulatory and breeding trials due to its sustainability as a no disease site.

As for Alupe, it is used for yield selection and trait selection trials. Three national agencies are jointly working together towards the final stages of research on the new cassava variety. National Environmental Management Authority is closely monitoring any possible impacts on the environment.

NBA is looking at aspects of food safety while Kephis is more concerned with suitability of the planting material when the new cassava is eventually released to farmers. Dr Taracha says the new variety will increase production and contribute towards actualisation of the anticipated flour-blending policy.