Genetic Characterization of Pepino Mosaic Virus Isolates from Morocco

Amal Souiri1, 2, 3, Mustapha Zemzami3, Hayat Laatiris3, Saaid Amzazi2, Moulay M. Ennaji1, *
1 Laboratory of Virology, Microbiology, Quality and Biotechnologies/Ecotoxicology and Biodiversity, Faculty of Science and Techniques Mohammedia, University Hassan II of Casablanca, Casablanca, Morocco
2 Laboratory of Biochemistry and Immunology, Faculty of Sciences, University of Mohammed V, Rabat, Morocco
3 Laboratory of Sanitary Control, Control Unit of Plants, Domaines Agricoles Maâmora, Salé, Morocco

© 2019 Souiri et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Laboratory of Virology Microbiology, Quality and Biotechnologies/Ecotoxicology and, Biodiverity - Faculty of Science and Techniques Mohammedia, University Hassan II of Casablanca, Mohammedia 20650, Morocco;
Tel: +212661748862 / +212662013772; E-mail:



Throughout the past few years, Pepino Mosaic Virus (PepMV) has rapidly evolved from an emerging virus to endemic pathogen that causes significant losses in tomato crops worldwide. Reliable detection and molecular characterization are very important tools to support disease control. Cross-protection can also be an effective strategy, but the efficacy depends strongly on the genotype. The genetic composition of the PepMV population in Morocco has not yet been determined.


The current study aims to genetically characterize twelve PepMV isolates (PepMV-MA), all from different Moroccan tomato production areas, by analyzing nucleotide sequences of a part of the RNA-dependent RNA polymerase (RdRp), Triple Gene Block (TGB) and Coat Protein (CP) genes.


The sequence analysis of the twelve PepMV-MA isolates shows minor nucleotide differences between them, which implies a homogenous population. The phylogenetic analysis, based on the comparison with the major genotypes, showed that Moroccan PepMV populations share a very high sequence identity, 98%, with the Chilean strain (CH2), while the shared identity with the European strains (EU) is only 85%. Interestingly, Moroccan isolates reveal specific single nucleotide polymorphisms, some of which lead to amino acids changes. These mutations have never been described before, suggesting distinct variants that may enhance aggressiveness and symptomatology.


Our careful sequence analysis and genotype determination, which placing homogenous Moroccan PepMV strains into CH2 genotype, would be a prerequisite for deploying effective cross-protection strategies for controlling the pathogen in the field.

Keywords: Pepino mosaic virus, Tomato, Genetic characterization, Morocco, CH2 genotype, Specific variations.