Abstract

Maize lethal necrosis (MLN) is the latest emerging disease of maize in Sub-saharan Africa. It was first reported in Uganda in 2013. Consequently, information regarding its prevalence, yield loss, applicable mitigation measures and socio-economic effects is still scanty, hence this study. A survey involving 300 respondents on the status of the disease was conducted in seven districts of eastern Uganda. Results revealed that MLN became prevalent in eastern Uganda in the first season of 2012 (2012A), which stretches from March to June. The MLN disease symptoms, especially chlorosis, were prevalent in most of the farmers’ fields in all the districts surveyed but particularly in Tororo, Mbale, Greater Sironko and Busia. Almost all farmers from the lowland areas reported MLN to be more destructive in the second season (B), which stretches from August to November. The disease can attack at any stage of crop growth from two weeks after planting. Very low yields (0.25 to 1.0 t ha^-1) attributed to the MLN epidemic, were obtained, causing an average yield loss of 50.5% valued at US$ 332 per hectare. Use of home saved seed especially in Busia, Tororo, Iganga and Mbale was common and partly explains the prevalence of MLN in these districts. Roguing emerged the most popular means farmers in eastern Uganda were using to control MLN. By intensifying MLN sensitization programmes, farmers will learn other management practices such as crop rotation, good sanitation practices and use of chemical sprays to control MLN. Finally expediting the breeding process for the development of MLN resistant or tolerant varieties will bring a lasting solution to the disease.

Key words: Eastern Uganda, DAS-ELISA, maize chlorotic mottle virus (MCMV), maize lethal necrosis (MLN).