CABI The Plantwise Blog Maize lethal necrosis disease on the decline in Kenya CIMMYT Maize Lethal Necrosis disease plant clinics Plant clinic data collected by Plantwise countries in East Africa has corroborated a statement from the International Maize and Wheat Improvement Center (CIMMYT) which said maize lethal necrosis disease (MLN) is “under control but not… Seed Inspectors can check for Maize lethal necrosis disease (MLND) in seed farms. In Summary An intensive multi-disciplinary and multi-institutional strategy is being implemented to curb the spread of MLN in sub-Saharan Africa, and mitigate the impact of the disease. Sustainable control of plant diseases requires a good understanding of the epidemiological aspects such as the biology of the causal pathogens. This disease is caused by co-infection of plants with two viruses – maize chlorotic mottle virus (MCMV) and sugarcane mosaic virus (SCMV) – and can cause yield losses of up to 90%. The Maize Lethal Necrosis Disease (MLND) is a result of a combination of two viruses, the Maize Chlorotic Mottle Virus (MCMoV) and any of the cereal viruses in the Potyviridae group, like the Sugarcane Mosaic Virus (SCMV), Wheat Streak Mosaic Virus (WSMV) or Maize Dwarf Mosaic Virus (MDMV). Maize lethal necrosis (MLN) is a disease that attacks maize crops with significant impacts on both food security and nutrition security on smallholder farmers in Kenya. Maize lethal necrosis disease (MLND) is a serious threat to maize production where it occurs. Its presence has been confirmed in Kenya, Rwanda, Tanzania, Democratic Republic of Congo, Uganda and Ethiopia. However, the observed symptoms were more severe than commonly associated with MCMV, suggesting the presence of maize lethal necrosis (MLN), a disease that results from maize infection with both MCMV and a potyvirus (4). Some maize varieties are resistant to the individual viruses. Maize lethal necrosis (MLN) emerged as a serious threat to maize production and livelihoods of smallholders in eastern Africa since 2011. In sub-Saharan Africa, maize is a staple food and key determinant of food security for smallholder farming communities. In a Nutshell. A plant health inspectorate organization can test for Maize chlorotic mottle virus (MCMV) in all seed coming into the country including the material for breeding. Maize lethal necrosis (MLN) is a new, devastating disease in East Africa that leads to severe production losses and, in many cases, complete crop failure. Maize Lethal Necrosis disease is spread through the air and farmers are advised to take these three immediate measures to contain further spread of the disease. Highlights Maize lethal necrosis (MLN) emerged as a serious threat to maize production and livelihoods of smallholders in eastern Africa since 2011. Maize Lethal Necrosis (MLN) Symptoms: Severe mottling of leaves, dead heart, stunted growth (shortened internode distance), leaf necrosis and barren ears. Keywords: maize lethal necrosis disease, distribution, incidence, severity, Uganda, maize 1. Internationally, MLND has been reported from Peru, USA, Argentina, Mexico, Thailand, razil … Called maize lethal necrosis (MLN; or corn lethal necrosis, CLN), it can devastate maize crops. MAIZE LETHAL NECROSIS HISTORY In September 2011, a disease outbreak in Kenya was positively identified as Maize Lethal Necrosis Disease (MLND). Maize Lethal Necrosis: The Disease MLN Diagnostic workshop, Naivasha, March 2014 Biswanath Das CIMMYT-Kenya 2. Symptoms similar to MLN were reported in Uganda, Tanzania, South Sudan and Ethiopia. The Ministry of Agriculture has warned that Maize Lethal Necrosis has been reported in districts in eastern Uganda, including Busia and Tororo. In September 2011, a serious disease outbreak, later diagnosed as maize lethal necrosis … Maize Lethal Necrosis disease, which was first reported in Kenya and Tanzania, has now spread to Uganda, raising concerns for food security in the country. Initial reports of maize lethal necrosis problems in East Africa were based on experiences by farmers and agricultural extension agents, complemented with diagnostics of the disease by international research organizations . Why this is a problem for New Zealand. 3. In severe infections, the whole plants withers and dead hearts are visible inside the stems. Of 17 symptomatic leaf samples from each Bomet and Naivasha, nine from Bomet and all 17 from Naivasha were positive for MCMV. High yield losses in maize due to MLN ranging from 50 to 90% have been reported and can reach 100% where the disease pressure is high. Maize lethal necrosis disease Multiple virus infections Once the disease enters a field there is little that can be done to prevent total loss of the crop. Maize lethal necrosis disease kills the leaves of plants. First report was in Kenya in 2012, since then the disease has rapidly spread to most parts of eastern and central Africa region including Tanzania, Burundi, DRC Congo, Rwanda, Uganda, Ethiopia and similar symptoms were observed in South Sudan. A spokesman for the Agriculture Research Organisation, Robert… Read Further. Maize Lethal Necrosis Disease (MLND) – A Review Temesgen Deressa * Girma Demissie National Maize Research centre; Ethiopian Institute of Agricultural Research (EIAR), P.O.Box 03, Bako, Ethiopia Maize lethal necrosis is a serious disease of maize in Africa from its first appearance in Kenya. Called maize lethal necrosis (MLN; or corn lethal necrosis, CLN), it can devastate maize crops. Shamba Shape Up episode featuring CROPNUTS Plant Disease Expert, Rose Nyakundi, who visited a farm in Busia that was once affected by Maize Lethal Necrosis Disease (MLND). Advanced symptoms include browning from the edge of the leaves, which does not occur in maize streak virus. The disease is difficult to control for two reasons: It is caused by a combination of two viruses that are difficult to differentiate individually based on visual symptoms. Since then the disease has been reported in Rwanda and DR . The study used spatial regression analysis to model MLN severity on sampled farm fields in Bomet County, Kenya. However, there don't seem to be maize varieties that can resist maize lethal necrosis disease. Introduction Maize (Zea mays L.) is a dietary staple and significant cash crop throughout the tropical world; serving as a food security crop for more than 70 million people in Sub Saharan Africa (Melinda et al., 2013). 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