Maize lethal necrosis and the molecular basis of variability in concentrations of the causal viruses in co-infected maize plant

L A O Awata; B E Ifie; P Tongoona; E Danquah; M B Jumbo; M Gowda; P W Marchelo-D'ragga; Chelang'at Sitonik; L M Suresh

doi:10.5897/JGMV2019.0073

Maize lethal necrosis and the molecular basis of variability in concentrations of the causal viruses in co-infected maize plant

J Gen Mol Virol. 2019;9(1). doi: 10.5897/JGMV2019.0073. Epub 2019 Jun 30.

Authors

L A O Awata¹, B E Ifie², P Tongoona², E Danquah², M B Jumbo³, M Gowda³, P W Marchelo-D'ragga⁴, Chelang'at Sitonik^{3

5}, L M Suresh³

Affiliations

¹ Directorate of Research, Ministry of Agriculture and Food Security, Ministries Complex, Parliament Road, P. O. Box 33, Juba, South Sudan.
² West Africa Centre for Crop Improvement (WACCI), College of Basic and Applied Sciences, University of Ghana, PMB 30, Legon, Ghana.
³ International Maize and Wheat Improvement Center (CIMMYT), World Agroforestry Centre (ICRAF), United Nations Avenue, Gigiri. P. O. Box 1041-00621, Nairobi, Kenya.
⁴ Department of Agricultural Sciences, College of Natural Resources and Environmental Studies, University of Juba, P. O. Box 82 Juba, South Sudan.
⁵ Department of Plant Breeding and Biotechnology, School of Agriculture and Biotechnology, University of Eldoret, P. O. Box 1125-30100, Eldoret, Kenya.

Abstract

Maize lethal necrosis (MLN) disease is new to Africa. 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. Elsewhere, the disease was caused by infection of Maize Chlorotic Mottle Virus (MCMV) in combination with any of the potyviruses namely; maize dwarf mosaic virus (MDMV), sugarcane mosaic virus (SCMV) and tritimovirus wheat streak mosaic virus (WSMV). In Africa, the disease occurs due to combined infections of maize by MCMV and SCMV, leading to severe yield losses. Efforts to address the disease spread have been ongoing. Serological techniques including enzyme-linked immuno-sorbent assay (ELISA), polymerase chain reaction (PCR), genome-wide association (GWAS) mapping and next generation sequencing have been effectively used to detect and characterize MLN causative pathogens. Various management strategies have been adapted to control MLN including use of resistant varieties, phytosanitary measures and better cultural practices. This review looks at the current knowledge on MLN causative viruses, genetic architecture and molecular basis underlying their synergistic interactions. Lastly, some research gaps towards MLN management will be identified. The information gathered may be useful for developing strategies towards future MLN management and maize improvement in Africa.

Keywords: Co-infection; Maize Chlorotic Mottle Virus (MCMV); maize; sugarcane mosaic virus (SCMV); synergism; virus.

Publication types

Review