Cassava viruses spread in East Africa

by Joseph Miti

For a long time, little attention has been paid to cassava growing as an economic activity in the Great Lakes region. Though cassava is one of the major staple foods in the region, less research has been done on amplifying the root crop’s production as well as controlling diseases that affect it.

These cassava diseases such as Cassava Brown Streak disease (CBSD) and Cassava Mosaic disease (CMD) spread like bush fires, threatening the region’s cassava. Prior to 2004, CMD was a single largest threat to cassava crop trailed by CBSD that had never been recorded at high incidence beyond, 1000 metres above sea level. CBSC was primarily known as a disease of the lowland cassava-growing areas in East Africa.

But since 2004, CBSD has been widespread in south-central Uganda; wiped out CMD-resistant varieties that are promoted for the management of the CMD pandemic.

However, due to food scarcity and soaring prices of cereals that have hit the region for the last five years, people came to understand the importance of the crop. This is when Food and Agriculture Organisation (FAO), International Institute of Tropical Agriculture (IITA), National Agriculture Research Organisation (NARO), and other organisations that promote food production joined efforts to comb both diseases.

According to Dr Christopher Omongo, a crop entomologist at National Crops Resources Research Institute Namulonge, Uganda is a county that is burdened by both diseases. He says the viruses affect about 55 per cent of the territory and the country currently has no varieties that are resistant to both diseases.

Dr Omongo attributes the spread of the viruses to free movement and diffusion of planting materials that are passed on to farmers by development partners. He says after the country was hit by food scarcity and soaring food prices, many development partners came in to bail out communities with cassava planting materials since cassava bears all conditions.

Development partners, however, supply varieties of cassava cutting in an uncoordinated manner, fueling cassava-diseases.

“Since in Uganda, everything was liberalised, many development partners diffuse various planting materials to different parts of the country and across boarders without seeking our advice,” Dr Omongo says. “We cannot stop people from helping the community, but we say that whoever wants to assist the society should seek for help from NARO.”

Free movement and diffusion of planting material does not bother only Uganda, but it affects all East and Central Africa countries. According to Cyril Ferrand, FAO Regiona Emergency Officer, CMD and CBSD have spread all over the region in the same mode, greatly threatening the crop.

Ferrand says though there are numerous projects being implemented all over the region to mitigate both diseases, actors face challenges of coordination and information sharing.

“We need coordination and this should be developed by the government. We are here to support the government in the fight of those diseases as well as to boost food production,” Ferrand says.

Parcy Misika, FAO county representative, says despite repeated humanitarian efforts, millions of people in Central and East Africa remain extremely vulnerable to hunger. He says Virulent Mosaic and brown streak disease strains continue to challenge the food security of millions and keeps researchers in search of new improved varieties.

“Threatening cassava, which has several advantages over rice, maize, and other grains, a staple food that suits areas where there is a degraded retain source base, variable rainfall, weak market infrastructure and uncertainty security situation, is a situation that calls for greater collaboration among all partners to achieve a sound emergency situation analysis and response,” Mikisa says.

He says the role of root and tuber crops is becoming increasingly important for smallholder farmers cropping on marginal and sub-marginal lands in the humid and sub-humid tropics. Consumers in several countries have been seen substituting cereals with less expensive staple food such as cassava in the recent months, the country representative says.

Cassava is efficient in carbohydrate production, adapted to a wide range of environments and tolerant to drought and acidic soils. In Africa, an estimated 70 million people obtain more than 500 Kcal per day from cassava.

According to Diana Oyena of Association for Strengthening Agricultural Research in East and Central Africa (Asareca), the organisation will disseminate information in different local languages using dissimilar media.

Oyenga says people need information about the disease to boost food production in communities.

Ferrand says they are advising people with contaminated plantations to uproot them as defensive mechanism and to ask for better varieties that can tolerate diseases from development partners.

http://www.monitor.co.ug/artman/publish/features/Agriculturalists_pledge_to_fight_cassava_viruses_80026.shtml