Virology Lab

Plant pests and pathogens can wipe out farmers’ hard work and cause significant losses to yields and incomes, posing a major threat to food and nutrition security of millions at a time. The lab integrate different approaches and digital open tools to understand, detect and keep track of the occurrence of transboundary pests and pathogens worldwide. From disease biological characterization, classic diagnostics and new generation sequencing tools, our laboratory support the work on characterization of pathogens, breeding for disease resistance and propagation of clean planting material. We developed the PestDisPlace platform (, designed to support in the organization and standardization of our work protocols carried out through different regional projects on specific pathogens.

PestDisPlace: Sri Lankan cassava mosaic virus (SLCMV) and the Cassava Mosaic Disease in Southeast Asia

SLCMV is one of several viruses that cause Cassava Mosaic Disease (CMD), a major disease of cassava in Africa and Asia. This particular virus isolate was reported for the first time in Sri Lanka in 1998, and its most recent emergence registered in 2015, in Southeast Asia. The PestDisPlace Reporter map below, shows the current information available on the occurrence of CMD caused by SLCMV. In all cases, the virus now reported in Southeast Asia, is more than 93% identical in nucleotide sequence to isolates from the South of India and Sri Lanka. We use the information obtained from the field on symptoms and vectors, to study the genetics of the pathogen, in this case we use the open source tool Nextstrain to display the changes in the population of the pathogen

Publications (Since 2012)

1.    He Y-Z, Wang Y-M, Yin T-Y, Cuellar WJ, Liu S-S, Wang X-W. 2021. Gut expressed vitellogenin facilitates the movement of a plant virus across the midgut wall in its insect vector. Submitted

2.    Kreuze JF, Cuellar WJ, Low J. 2021. Chapter 5: Challenge of virus disease threats to ensuring sustained uptake of vitamin-A-rich sweetpotato in Africa. In: Plant Health in a Global Economy. Springer Nature Eds. In press.

3.    Chittarah K, Jimenez J, Vongphachanh P, Leiva AM, Sengsay S, Lopez-Alvarez D, Bounvilayvong T, Lourido D, Vorlachith V, Cuellar WJ. 2021. First report of Cassava Mosaic Disease and Sri Lankan Cassava mosaic virus in Laos. Plant Disease.

4.    Ovalle TM, Vásquez-Ordóñez AA, Jimenez J, Parsa S, Cuellar WJ, Becerra Lopez-Lavalle LA. 2020. A simple PCR-based method for the rapid and accurate identification of cassava mites. Scientific Reports.

5.    Lopez-Alvarez D, Parra B, Cuellar WJ. 2020. Genome sequence of SARS-CoV-2 isolate Cali-01 from Colombia, obtained using Oxford Nanopore Technology. Microbiology Resource Announcements.

6.    Lopez-Alvarez, D;  Leiva AM; Barrantes I; Pardo JM; Dominguez V, Cuellar WJ. 2020. Complete genome sequence of the plant pathogen Ralstonia solanacearum CIAT-078 from Colombia using Oxford Nanopore Technology. Microbiology Resource Announcements.

7.    Siriwan W, Jimenez J, Hemniam N, Saokham K, Lopez-Alvarez D, Leiva AM, Martinez A, Mwanzia L, Becerra LA, Cuellar WJ. 2020. Surveillance and diagnostics of the emergent Sri Lankan cassava mosaic virus in Southeast Asia. Virus Research.

8.    Xing et al., 2020. Global cropland connectivity: a risk factor for invasion and saturation by emerging pathogens and pests. BioScience.

9.    Silvestre R, Fuentes S, Risco R, Berrocal A, Adams I, Fox A, Cuellar WJ, Kreuze J. 2020. Characterization of distinct strains of an aphid-transmitted ilarvirus (Fam. Bromoviridae) infecting different hosts in South America. Virus Research.

10.    Kreuze JF, Perez A, Galvez M, Cuellar WJ. 2020. Badnaviruses of sweetpotato: symptomless co-inhabitants on a global scale. Frontiers in Plant Science.

11.    Leiva AM; Siriwan W; Lopez-Alvarez D; Barrantes I; Hemniam N; Saokham K; Cuellar WJ. 2020. Nanopore-based complete genome sequence of a Sri Lankan cassava mosaic virus strain from Thailand. Microbiology Resource Announcements.

12.    Pardo JM, Lopez D, Ceballos G, Alvarez E, Cuellar WJ. 2019. Detection of Ralstonia solanacearum phylotype II, race 2 causing Moko disease and validation of resistance observed in the hybrid plantain FHIA-21. Tropical Plant Pathology.

13.    Cuellar WJ, Mwanzia L, Lourido D, Garcia C, Martínez A, Cruz P, Pino L, Tohme J. 2018. PestDisPlace: Monitoring the distribution of pests and diseases. Version 2.0 International Center for Tropical Agriculture (CIAT). Available at:

14.    Cutler J, et al., Cuellar WJ, Buttner C. 2018. Preliminary evaluation of associated viruses in production systems of cape gooseberry, purple passion fruit, and rose. Revista Colombiana De Ciencias Hortícolas 12, 390-396.


Head: Wilmer J. Cuellar, PhD (ORCID:  



Crops for Nutrition and Health, The Americas Hub. 

2017: Regional representative of the International Committee for Plant Virus Epidemiology (ICPVE) ( 

2018: Leader of cluster CA3.5: Cassava Biological Threats in Asia and the Americas (CGIAR Research Program on Roots, Tubers and Bananas) (

Email: [email protected]  

Tel: (57-2)445 0000 Ext. 3379