Africa cuts new cases of top maize disease
- Maize lethal necrosis causes up to 100 per cent yield losses
- Interventions have led to success against the disease in some African nations
- Efforts are needed to help smallholders access disease-resistant maize varieties
Maize lethal necrosis, a disease caused by a set of viruses, results in up to 100 per cent yield losses, thus having a devastating impact on food security and smallholders’ incomes in Sub-Saharan Africa, according to the International Maize and Wheat Improvement Center (CIMMYT).
“We have seen clear reduction of severity [of the disease] in a number of countries across East Africa,” said Boddupalli Prasanna, director of the global maize program at CIMMYT, during a meeting last month (18-19 November) in Kenya to review progress in fighting the disease. “This disease has been a big threat to agricultural production in East Africa in the last six years.”
For example, new cases of the disease in Kenya, Rwanda and Tanzania have reduced from 65 per cent, 35 per cent and 43 per cent to about 29 per cent, 25 per cent and 11 per cent, respectively from 2015 to 2018.
According to Prasanna, interventions such as destruction of infected plants and control of insect vectors in Rwanda aided the improvement in fighting the disease.
“We have seen clear reduction of severity [of the disease] in a number of countries across East Africa.”
Boddupalli Prasanna, CIMMYT
Fidele Nizeyimana, a maize pathologist at Rwanda Agriculture Board, added that an awareness programme facilitated the country’s progress in reducing new cases of the disease.
The review meeting brought together research scientists, commercial seed companies and policymakers from countries such as Ethiopia, Kenya, Malawi, Tanzania, Zambia and Zimbabwe to discuss lessons learnt and experiences in managing the disease in Sub-Saharan Africa.
Francis Mwatuni, manager of CIMMYT’s project for diagnosing and diagnosing the disease, added that interventions such as disease-resistant maize varieties have helped cut the threat of the disease’s spread in East and Southern Africa.
According to Johnny Masangwa, a plant pathologist from Malawi’s Ministry of Agriculture, Irrigation and Water Development, surveillance has shown Malawi as being free of maize lethal necrosis in the past three years.
Prasanna cautioned that East Africa is not yet free of the disease because there are new reports in Uganda. He told participants that the new reports of the disease in eastern parts of Uganda should be analysed and managed quickly because it could lead to the upsurge of the disease in the bordering areas of western Kenya. Isaac Macharia, a senior research fellow at the Kenya Plant Health Inspectorate Service, lauded commercial seed companies in the region for ensuring that farmers get disease-free seeds.
Macharia said that more than 12 maize varieties resistant to the disease have been released and are ready for commercialisation in Kenya, Tanzania and Uganda next year.
“What we want is ensuring that these products are readily available and accessed, especially by smallholders.” Macharia said. “We want to ensure that we are fully in control of the disease.”
This piece was produced by SciDev.Net’s Sub-Saharan Africa English desk.