NEW PEST OF MAIZE: MAIZE LETHAL NECROSIS IN RWANDA

Publication Date

Wed, 15 Jul 2015, 07:48

Last Updated

July 15, 2015, 7:48 a.m.

Report Number

RWA-01/1

Country

Rwanda

Pest Id

Maize chlorotic mottle virus - (MCMV00)

Report Status

Preliminary

Hosts

Zea mays

Pest Status (old values from ISPM 8 -1998 )

• Present: subject to official control
• Transient: actionable, under surveillance

Pest Status (ISPM 8 - 2021)

• Present: not widely distributed and under official control
• Present: transient

Geographical Distribution

All volcanic highlands, some parts of Buberuka highlands as well as a few sites on the Congo-Nil trail

Summary

Summary: Maize lethal necrosis (MLN) is a viral disease of maize caused by the combination of Maize chlorotic mottle virus (MCMV) and one of viruses in the Potyviridae family such as Sugarcane Mosaic Virus (SCMV), Maize Dwarf Mosaic Virus (MDMV) or Wheat Streak Mosaic Virus (WSMV). In Rwanda, the disease was identified in 2013; it was reported to be caused by a combination of two viruses MCMV and the potyvirus Sugarcane mosaic virus (SCMV). MCMV is new in the country and is thought to be transmitted mechanically or by insect vectors (thrips and beetles) as well as seed while SCMV is endemic. Symptoms of MLN disease include leaf mottling and necrosis, stunting and failure to produce tassels, immature ear husks showing yellow streaks, ears appearing physiologically mature, kernels inside are still at milk stage while the rest of the plant is still green. Infected plants form small cobs with few grains or on grains; necrosis of young leaves in the whorl before expansion leading to the death of the whole plant.

Danger

The disease can cause yield loss up to 100% in highly infected sites

Contact for info

Director General, Agriculture and Livestock Inspection and Certification Services Ministry of Agriculture and Animal Resources P o.Box 621 Kigali email: [email protected] [email protected]

Report files

Website

Issue keywords

Surveillance Viruses/virus like organisms

Commodity keywords