Maize lethal necrosis: an emerging disease in Africa
Maize lethal necrosis is an emerging disease of maize (Zea mays) crops in Africa which is caused by a combination of Maize chlorotic mottle virus (Machlomovirus, MCMV) with a maize-infecting Potyviridae, such as Sugarcane mosaic virus (Potyvirus, SCMV), Maize dwarf mosaic virus (Potyvirus, MDMV), or Wheat streak mosaic virus (Tritimovirus, WSMS). Early symptoms are leaf mottling and chlorosis which can be followed by leaf deformation and extensive necrosis. Stems can also be deformed. Severely affected plants have small cobs with little or no grain production. Infection rates and impact on yield can be very high, and in some cases total loss of maize crops has been observed. It is suspected that this disease is transmitted by insect vectors (such as maize thrips, rootworms, or leaf beetles), and possibly by seeds (at a low rate). Since its initial discovery in Kenya in 2011, maize lethal necrosis has been reported from other African countries: Democratic Republic of Congo, Ethiopia, Mozambique, Rwanda, South Sudan, Tanzania, and Uganda. Research is being carried out to better understand the biology and epidemiology of this severe disease, and to develop control strategies.
Adams IP, Harju VA, Hodges T, Hany U, Skelton A, Rai S, Deka MK, Smith J, Fox A, Uzayisenga B, Ngaboyisonga C, Uwumukiza B, Rutikanga A, Rutherford M, Ricthis B, Phiri N, Boonham N (2014) First report of maize lethal necrosis disease in Rwanda. New Disease Reports 29, 22. [http://dx.doi.org/10.5197/j.2044-0588.2014.029.022
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- Kenya (KEN-02/1 of 2014-06-27) Status of maize lethal necrosis disease (MLND) in Kenya. https://www.ippc.int/en/countries/Kenya/pestreports/2014/06/status-of-maize-lethal-necrosis-disease-mlndin-kenya/
– Rwanda (RWA-01/1 of 2015-07-15) New pest of maize: maize lethal necrosis in Rwanda. https://www.ippc.int/en/countries/rwanda/pestreports/2015/07/new-pest-of-maize-maize-lethal-necrosis-in-rwanda/
– Uganda (UGA-01/2 of 2013-06-19) New pest of maize: maize lethal necrosis in Uganda. https://www.ippc.int/en/countries/Uganda/pestreports/2013/04/new-pest-of-maize-maize-lethal-necrosis-in-uganda/
- posting (no. 20150130.3130105 of 2015-01-29) Lethal necrosis, maize - Ethiopia: 1st report. http://www.promedmail.org/direct.php?id=3130105
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- posting (no. 20140604.2518403 of 2014-06-04) Lethal necrosis, maize - Rwanda: 1st report (Northern Province) http://www.promedmail.org/direct.php?id=2518403
- posting (no. 20131004.1983210 of 2013-10-04) Lethal necrosis, maize - Mozambique: 1st report. http://www.promedmail.org/direct.php?id=1983210
- posting (no. 20130403.1620327 of 2013-04-03) Lethal necrosis, maize - Uganda, Tanzania: 1st reports. http://www.promedmail.org/direct.php?id=1620327
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